Control method for a pellet stove based on moisture detection and feed system for a pellet stove

Abstract

The present invention provides a control method for a pellet stove based on moisture detection and a feeding system for a pellet stove, wherein the pellet stove is switched on to activate its feeding system and a moisture sensor on the feeding system. The moisture sensor is used to continuously monitor the moisture content of the fuel feed channel in which the pellet fuel has been stored in the feeding system, enabling the control unit to assess the moisture level of the surrounding environment or of the pellet fuel in the fuel feed channel. The present invention protects the feeding system and thus reduces maintenance costs by preventing fuel that has become powdery due to moisture from drying out again into hard lumps in the fuel feed channel, which can lead to a blockage of the auger.

Description

Technical field

[0001] The present invention relates to the technical field of pellet fuel feed control for a pellet stove, in particular a control method for a pellet stove based on moisture detection and a feed system for a pellet stove. State of the art

[0002] Pellet stoves are generally used as ovens for cooking food, such as the "ARRANGE OF COMPONENTS WITHIN A COOKING DEVICE" developed in US Patent Publication No. US20230309743A1, which consists of a combustion chamber, a cooking structure positioned above the combustion chamber, and a pellet fuel feed system connected to the combustion chamber. In use, the feed system conveys the pellet fuel into the combustion chamber to be burned on the cooking structure for cooking food. The feed system includes a fuel feed channel and an auger located within the fuel feed channel. Pellet stoves are typically used outdoors, where high humidity, fog, rain, and other weather conditions can cause the pellet fuel in the stove's feed system to become damp if not thoroughly cleaned by the user.

[0003] For example, the German patent specification "Control device for a biomass combustion device and method for controlling a biomass combustion device" under publication number DE102010032090A1 discloses a method. The method is carried out by means of a detection device located at a defined position of a feed device. The feed device feeds material into a combustion chamber for combustion. Based on the detected back pressure of the material, a control signal is issued to control a conveying device that delivers the material to the feed device. The conveying device is stopped and / or returned to a reverse mode by the control signal.For example, the German patent specification "Method for ensuring a constant, predetermined rise rate for pellet- or wood-fired stoves, in particular for baking ovens, especially for industry and trade" under publication number DE102013101333A1 describes a method for ensuring a constant rise rate for pellet stoves. For example, the Austrian patent specification "Method for controlling a heating appliance" under publication number AT512398A4 describes a method that monitors the motor current of a conveying device and thereby detects an accumulation of pellet fuel.

[0004] Therefore, the existing feed system for a pellet stove has the following disadvantages: 1. If the pellet stove mentioned above is not used for an extended period, the pellet fuel swells and clumps when damp, forming hard lumps when dry. This can cause the auger conveyor of the feed system to become abnormally clogged, impairing the machine's operation. Furthermore, maintenance costs are very high when the auger conveyor of the feed system is clogged, requiring significant labor after the sale. 2. During ignition, the moist pellet fuel is fed into the combustion chamber, leading to ignition failures and reducing the efficiency of the machine.

[0005] Therefore, due to the aforementioned disadvantages, there is an urgent need for a pellet stove design that can solve the aforementioned technical problems. Content of the present invention

[0006] To solve the aforementioned technical problems, the present invention provides a control method for a pellet stove based on moisture detection and a feeding system for a pellet stove.

[0007] The present invention develops a control method for a pellet stove based on moisture detection, comprising the following steps: S1. Switching on the pellet stove to simultaneously switch on its feed system and a humidity sensor located on the feed system; S2. Using the humidity sensor to continuously monitor the humidity of the fuel conveying channel in which the pellet fuel was stored in the feed system, by enabling the control unit to assess the humidity level of the spatial environment or the pellet fuel in the fuel conveying channel; If it is determined that the spatial environment or the pellet fuel in the fuel feed channel is in a state of high humidity, the pellet stove control unit controls the feed system to enter a return mode, thereby returning the pellet fuel to the feed inlet of the feed system, or controls the pellet stove to enter a drying ignition mode, or controls the pellet stove to enter an anti-extinguishing mode; If it is determined that the spatial environment or the pellet fuel in the fuel feed channel is in a state of low humidity, the pellet stove's feed system enters feed mode under the control of the control unit.

[0008] According to the above control method for a pellet stove based on humidity sensing, the humidity sensor is a humidity-sensitive resistor, and the current humidity of the spatial environment or of the pellet fuel in the fuel conveying channel is assessed according to the value of the humidity-sensitive resistor; If the value of the moisture-sensitive resistor is less than the predetermined resistance value, the pellet stove's control unit determines that the current spatial environment or the pellet fuel in the fuel feed channel has a high moisture content; If the value of the moisture-sensitive resistor is greater than the predetermined resistance value, the pellet stove's control unit determines that the current spatial environment or the pellet fuel in the fuel feed channel has low moisture content.

[0009] According to the above control procedure for a pellet stove based on moisture detection, an additional step for detecting a blockage-free return signal is arranged before entering return mode, which includes the following: Assessing and recognizing from the control unit whether the blockage-free return indicator is in the non-zero position when the value of the moisture-sensitive resistance is less than the predetermined resistance value; Return to monitor the humidity again if the unblocked return indicator is in the non-zero position; Entering return mode according to the high moisture content occurs when the unblocked return indicator is in the zero position. According to the above control procedure for a moisture-sensing-based pellet stove, the control unit, in return mode, controls the feeding system to perform a return at a predetermined time and to set the return indicator to a non-zero position when the return time has elapsed. According to the above control procedure for a pellet stove based on moisture detection, if the value of the moisture-sensitive resistance is greater than a predetermined resistance value, the control unit controls the feeding system so that it performs a feed in feed mode at a predetermined time, and that it sets the return signal to zero when the feed time is complete. According to the above control procedure for a pellet stove based on moisture detection, the procedure further includes the following: Step S3. Assess whether a user ignition process is being performed; If the user ignition process is not performed, the humidity monitoring will be performed again; When the user ignition process is performed, it is determined whether the clog-free return signal is in a non-zero position; where, if the clog-free return signal is in a non-zero position, it means that the return was performed prior to the user ignition process to control the feeding system to operate for feeding at a predetermined time and to enter ignition mode upon completion of the feeding time; and where, if the clog-free return signal is in a zero position, it means that the return was performed prior to the user ignition process, and it enters ignition mode directly upon detection of the signal. According to the above control procedure for a pellet stove based on moisture detection, the ignition mode includes the following: a drying ignition mode, whereby it enters this mode when the value of the moisture-sensitive resistance is less than a predetermined resistance value and it is determined that the spatial environment or the pellet fuel in the fuel conveying channel is currently in a state with high moisture content; After entering drying ignition mode, the control unit regulates the feed system so that it feeds the pellet fuel into the combustion chamber at a predetermined time. Once the feed time is complete, the ignition rod in the combustion chamber opens and ignites the wet pellet fuel at a predetermined time. Simultaneously, the fan operates continuously and intermittently to supply the combustion chamber with air and oxygen. The system then enters a waiting period of a predetermined time. After this waiting period, it is determined whether the temperature of the combustion chamber exceeds a predetermined temperature value. If the temperature of the combustion chamber is higher than the predetermined temperature value, ignition will be successful; If the temperature of the combustion chamber is lower than the predetermined temperature value, the control unit controls the feeding system so that at a predetermined time it performs the feeding to re-feed the pellet fuel into the combustion chamber, and the drying ignition mode is repeated until ignition is successful; According to the above control method for a pellet stove based on humidity detection, the ignition mode further includes the following: a normal ignition mode, whereby it enters this mode when the value of the moisture-sensitive resistance is greater than a predetermined resistance value and it is determined that the spatial environment or the pellet fuel in the fuel conveying channel is in a current state with low moisture content; After entering normal ignition mode, the control unit controls the feed system so that it carries out the feed at a predetermined time to convey the pellet fuel into the combustion chamber, and the ignition rod in the combustion chamber is opened after the feed time has elapsed, and the fan operates simultaneously in a continuous and intermittent manner to supply the combustion chamber with air and oxygen, and then enters a waiting period of predetermined time, and after the waiting period has elapsed it is determined whether the temperature of the combustion chamber is greater than a predetermined temperature value; If the temperature of the combustion chamber is higher than the predetermined temperature value, ignition is successful; If the temperature of the combustion chamber is lower than the predetermined temperature value, the control unit controls the feeding system to perform the feeding at a predetermined time to re-feed the pellet fuel into the combustion chamber, and the drying ignition mode is performed again until ignition is successful.

[0010] According to the above control method for a pellet stove based on moisture detection, it further includes the following: Step S4. After successful ignition, assess whether the value of the moisture-sensitive resistor is lower than the predetermined resistance value; If, after successful ignition, it is determined that the value of the moisture-sensitive resistance is less than the predetermined resistance value, it is determined that the spatial environment or the pellet fuel in the fuel conveying channel has a high moisture content, and it enters the anti-extinguishing mode directly; If, after successful ignition, the value of the moisture-sensitive resistor is determined to be greater than the predetermined resistance value, it is determined that the ambient environment or the pellet fuel in the fuel feed channel has low humidity, and it enters normal ignition mode directly. In this mode, the control unit regulates the feed system so that it performs the feed at a predetermined time to convey the pellet fuel into the combustion chamber, and the fan simultaneously operates continuously and intermittently to supply the combustion chamber with air and oxygen. Then, a waiting period of predetermined time is entered, and humidity monitoring is performed again after the waiting period has ended.According to the above control procedure for a pellet stove based on humidity detection, after entering anti-extinguishing mode, the control unit controls the feed system so that it carries out the feed at a predetermined time to convey the pellet fuel into the combustion chamber. After the feed time has elapsed, it opens the ignition rod and continues the feed in a continuous and intermittent manner. The fan operates continuously and intermittently to supply the combustion chamber with air and oxygen. Then, a waiting period of a predetermined time is entered, and humidity monitoring is performed again after the waiting period has ended. Furthermore, the feed system for a pellet stove comprises the following: a screw conveyor, wherein the screw conveyor has a fuel conveying channel, comprising a screw arranged in the fuel conveying channel and a rotary drive device used to drive the rotation of the screw, wherein the outlet of the fuel delivery channel is connected to the feed opening of the combustion chamber; a humidity sensor, wherein the humidity sensor is arranged on a wall of the fuel conveying channel; and a control unit, wherein the rotary drive device and the humidity sensor are each connected to and controlled by the control unit.

[0011] According to the above feed system for a pellet stove, the wall of the fuel conveying channel includes an outer wall and a through hole, the induction section of the moisture sensor is located on the outer wall, and the induction section of the moisture sensor is located in a position corresponding to the position of the through hole.

[0012] According to the above pellet stove feed system, a moisture-absorbing material is arranged between the outer wall and the induction section of the humidity sensor, and the upper and lower side surfaces of the moisture-absorbing material are attached to the outer wall and the induction section of the humidity sensor, respectively, and the moisture-absorbing material covers the through-hole. According to the above pellet stove feed system, the wall of the fuel conveying channel comprises an inner wall and a through-hole, and at least part of the humidity sensor is embedded in the through-hole such that the induction section of the humidity sensor is flush with the inner wall, or the induction section of the humidity sensor protrudes from the inner wall, or the induction section of the humidity sensor is located within the through-hole.According to the above feed system for a pellet stove, the wall of the fuel conveying channel includes an inner wall, and the moisture sensor is located on the inner wall and is in direct contact with the pellet fuel in the fuel conveying channel.

[0013] According to the above feed system for a pellet stove, the humidity sensor is located in the area between a feed inlet and the outlet on the fuel feed channel, or The humidity sensor is located in an area of ​​the feed inlet on the fuel delivery channel.

[0014] According to the above feed system for a pellet stove, the moisture sensor is located on the upper or lower side of the fuel feed channel.

[0015] According to the above feed system for a pellet stove, the humidity sensor is attached to the outer wall using a housing, and the moisture-absorbing material is attached inside the housing.

[0016] The present invention provides a control method for a pellet stove based on moisture detection and a feeding system for a pellet stove, which have the following advantageous effects: 1. Moisture in the fuel feed channel is detected by a moisture sensor located on the fuel feed channel. If the control unit determines that the moisture level is high based on the moisture value reported by the sensor, it controls the feeding system to return the moist, granular fuel to the feed inlet of the fuel feed channel. This prevents the fuel in the fuel feed channel from drying into hard lumps and becoming powdery due to moisture, which would lead to a blockage of the screw conveyor. This protects the feeding system and thus reduces maintenance costs. 2. When the pellet stove is used outdoors for cooking, the control unit detects the high ambient humidity and the high moisture content of the pellet fuel in the fuel feed channel when the stove is switched on. Therefore, the drying ignition mode is activated simultaneously with the fuel feed to dry the wet fuel being fed into the combustion chamber by the ignition rod. Ignition is then completed by continuously operating the ignition rod and the fan, thus resolving the technical problem of wet pellet fuel being difficult to ignite. Description of the drawings Fig. Figure 1 is a schematic representation of the overall structure of the pellet stove; Fig. Figure 2 is a schematic representation II of the overall structure of the pellet stove; Fig. Figure 3 is a schematic representation I of the structure during the assembly of the feed system in the furnace body of the pellet stove; Fig. Figure 4 is a schematic representation II of the structure during the assembly of the feed system in the furnace body of the pellet stove; Fig. Figure 5 is a schematic representation III of the structure during the assembly of the feed system in the furnace body of the pellet stove; Fig. Figure 6 is a schematic representation IV of the structure during the assembly of the feed system in the furnace body of the pellet stove; Fig. Figure 7 is a schematic representation V of the structure during the assembly of the feed system in the furnace body of the pellet stove; Fig. Figure 8 is a schematic representation of the structure when the housing is mounted on the outer wall of the fuel delivery channel; Fig. Figure 9 is a schematic representation of the overall structure; Fig. Figure 10 is a schematic flowchart of the intelligent anti-congestion function; Fig. 11 is a schematic flowchart for the ignition mode; Fig. Figure 12 is a schematic flowchart for the anti-extinguishing mode.

[0017] Reference list: 1. Furnace body; 11. Combustion chamber; 111. Ventilation hole; 112. Feed opening; 12. Assembly space; 13. Exhaust opening; 14. Electronic ignition rod; 2. Auger conveyor; 21. Fuel feed channel; 211. Feed inlet; 212. Outlet; 213. Through hole; 22. Auger; 3. Blower; 4. Motor; 5. Feed hopper; 6. Humidity sensor; 7. Moisture-absorbing material; 8. Housing; 9. Wall; 91. Outer wall; 92. Inner wall. Detailed embodiment

[0018] The technical solutions in the embodiments of this utility model are clearly and completely described below in conjunction with the attached drawings. Naturally, the described embodiments represent only a subset of the embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments that a person skilled in the art might obtain also fall within the scope of protection of this utility model. Design 1

[0019] As in the Fig. Figures 1 to 3 and 8 show that the pellet stove feeding system described in this embodiment comprises a screw conveyor 2, a moisture sensor 6 and a control unit, wherein the moisture sensor 6 generally uses a cost-effective, moisture-sensitive resistor, which allows for a reduction in production costs and labor costs for maintaining the pellet stove at a later stage.

[0020] The screw conveyor 2 comprises a fuel conveying channel 21, a screw 22 arranged in the fuel conveying channel 21, and a rotary drive device for rotating the screw 22, with an outlet 212 of the fuel conveying channel 21 being connected to a feed opening 112 of the combustion chamber 11. The rotary drive device drives the screw 22 to rotate in order to convey the pellet fuel, which enters from the feed inlet 211 of the fuel conveying channel 21, to its outlet 212 and into the combustion chamber 11, and the moisture sensor 6 is arranged on the wall 9 of the fuel conveying channel 21. The rotary drive device comprises a motor 4, the rotating shaft of which is connected to one end of the screw 22 near the feed inlet 211 of the fuel conveying channel 21, or the rotating shaft of the motor 4 is connected to one end of the screw 22 near the feed inlet 211 of the fuel conveying channel 21 by a transmission mechanism.The motor 4 and the moisture sensor 6 are each connected to and controlled by a control unit, which includes an MCU chip with a built-in program for controlling the motor 4 and the moisture sensor 6, and the motor 4 rotates the auger 22 so that the pellet fuel in the fuel conveying channel 21 is conveyed to the outlet 212 or the pellet fuel is drawn back to the feed inlet 211.

[0021] In particular, the wall 9 of the fuel conveying channel 21 comprises an outer wall 91 and a through-hole 213. The induction section of the humidity sensor 6 is located on the outer wall 91. The induction section of the humidity sensor 6 and the through-hole 213 are located at a position corresponding to the position of the through-hole 213. A moisture-absorbing material 7 is located between the outer wall 91 and the induction section of the humidity sensor 6. The moisture-absorbing material 7 generally consists of polyamide fibers. The upper and lower sides of the moisture-absorbing material 7 are bonded to the outer wall 91 and the induction section of the humidity sensor 6, respectively. The moisture-absorbing material 7 covers the through-hole 213, as shown in Fig. 8 shown, and the humidity sensor 6 is attached to the outer wall 91 via the housing 8, which is attached to the outer wall 91 by a screw or weld fastening, or

[0022] As in the Fig. As shown in Figures 1, 2, and 4 to 6, the wall 9 of the fuel conveying channel 21 comprises an inner wall 92 and a through-hole 213, and at least a portion of the humidity sensor 6 is embedded in the through-hole 213 such that the induction section of the humidity sensor 6 is flush with the inner wall 92, or the induction section of the humidity sensor 6 protrudes from the inner wall 92, or the induction section of the humidity sensor 6 is located in the through-hole 213. In this solution, no moisture-absorbing material 7 is required.

[0023] Preferably, the humidity sensor 6 is located in the area between the supply inlet 211 and the outlet 212 on the fuel conveying channel 21, and the humidity sensor 6 is attached to the upper outer wall 91 or the lower outer wall 91 in this area by the housing 8. Accordingly, a through-hole 213 is formed in the wall 9 of the fuel conveying channel 21 in the area between the supply inlet 211 and the outlet 212.The through-hole 213 is located on the top or bottom of the area and is arranged such that the humidity sensor 6 is attached in a position corresponding to the position of the through-hole 213, and the through-hole 213 can be arranged in a variety of positions, or the humidity sensor 6 is located in the area of ​​the feed inlet 211 on the fuel feed channel 21 and the humidity sensor 6 is attached in this area by the housing 8 to the upper outer wall 91 or the lower outer wall 91.Accordingly, a through-hole 213 is formed in the wall 9 of the fuel conveying channel 21 in the area of ​​the feed inlet 211, which is located on the upper side or the lower side of the area, so that the moisture sensor 6 is attached in such a way that it is arranged in a position corresponding to the position of the through-hole 213, and the through-holes 213 can be provided in several places.

[0024] Based on the structure above, the moisture sensor 6 is used to detect the moisture in the fuel feed channel 21. If the control unit determines that the moisture value reported by the moisture sensor 6 exceeds a predetermined threshold set by the control unit, the control unit controls the motor 4 to rotate and drive the auger 22 in reverse, so that the pellet fuel in the fuel feed channel 21 is recovered up to the position of the feed inlet 211, and all the moist pellet fuel is continuously recovered to the feed inlet 211.

[0025] In this embodiment, the feed inlet 211 of the fuel conveying channel 21 has a feed funnel 5, which is connected to the feed inlet 211 of the fuel conveying channel 21 and is located at one end of the fuel conveying channel 21 near the rotary drive device. The feed funnel 5 is arranged so that the pellet fuel in the storage can easily enter the fuel conveying channel 21 while the pellet fuel is conveyed into the combustion chamber 11. The feed inlet 211 and the outlet 212 of the fuel conveying channel 21 are far apart, so that the fuel conveying channel 21 has the function of storing the fuel and can be maintained for a certain period of time for combustion in the combustion chamber 11, even if there is no fuel in the storage.

[0026] The lower side surface of the humidity sensor 6 serves as an induction section, and the housing 8 can be welded or screwed to the outer wall 92.

[0027] In another embodiment, as in Fig. As shown in Figure 7, the wall 9 of the fuel conveying channel 21 comprises an inner wall 92, and the moisture sensor 6 is arranged on the inner wall 92 and is in direct contact with the pellet fuel in the fuel conveying channel 21, which is structured to enable better detection of the fuel's moisture content. The moisture sensor 6 is located in the area between the feed inlet 211 and the outlet 212 on the fuel conveying channel 21 and is attached in this area to the upper or lower inner wall 92 by fasteners, or the moisture sensor 6 is located in the area of ​​the feed inlet 211 on the fuel conveying channel 21 and is attached in this area to the upper or lower inner wall 92 by means of fasteners, the fasteners being bolts.

[0028] The feed system described above is installed in the furnace body 1 of the pellet stove, as in the Fig. Figures 1 to 7 are shown. The stove body 1 of the pellet stove includes a combustion chamber 11 for burning pellets. The stove body 1 has a rectangular structure, and the auger conveyor 2 and the electronic ignition rod 14 are arranged in the mounting space 12 of the stove body 1. The ignition end of the electronic ignition rod 14 is located in the combustion chamber 11. The combustion chamber 11 is provided with a ventilation opening 111, which is connected to the mounting space 12 of the stove body 1. The stove body 1 is provided with an exhaust opening 13, and a blower 3 is installed at the exhaust opening 13. The air blown by the blower 3 when it is in operation enters the combustion chamber 11 through the ventilation opening 111, supplying the combustion chamber 11 with sufficient oxygen and promoting combustion. Design 2

[0029] As in Fig. As shown in Figure 9, the control method for a pellet stove based on moisture detection described in the present embodiment comprises the use of a feeding system as in embodiment 1 for the feeding of pellet fuel and moisture detection after feeding, and the steps of moisture detection after feeding are as follows: S1: The pellet stove is switched on to activate its feed system and a humidity sensor on the feed system, the humidity sensor being located on the fuel feed channel 21 of the feed system. As shown in Fig. As shown in Figure 3, the feeding system uses a screw conveyor, wherein the screw conveyor comprises a fuel conveying channel 21, a screw 22 arranged in the fuel conveying channel 21 and a motor 4 for driving the screw to rotate, and the outlet 212 of the fuel conveying channel 21 and the ignition head of the electronic ignition rod 14 are located inside the combustion chamber 11.

[0030] The wall 9 of the fuel conveying channel 21 comprises an outer wall 91 and a through-hole 213. An induction section of the humidity sensor 6 is arranged on the outer wall 91. The induction section of the humidity sensor 6 is positioned corresponding to the position of the through-hole 213. A moisture-absorbing material 7 is arranged between the outer wall 91 and the induction section of the humidity sensor 6. The moisture-absorbing material 7 generally consists of polyamide fibers. The upper and lower sides of the moisture-absorbing material 7 are attached to the outer wall 91 and the induction section of the humidity sensor 6, respectively. The moisture-absorbing material 7 covers the through-hole 213. The humidity sensor 6 is attached to the outer wall 91 by the housing 8.Preferably, the humidity sensor 6 is located in the area between the supply inlet 211 and the outlet 212 of the fuel conveying channel 21, and the humidity sensor 6 is attached in this area to the upper or lower outer wall 91 by means of the housing 8. Accordingly, a through-hole 213 is formed in the wall 9 of the fuel conveying channel 21 in the area between the supply inlet 211 and the outlet 212, located on the upper or lower side of this area. After the humidity sensor 6 has been attached so that it is positioned corresponding to the position of the through-hole 213, the through-hole 213 can be arranged in a plurality of positions.wherein the screw conveyor 2 and the combustion chamber 11 are both arranged in the furnace body 1, wherein the ventilation holes 111 in the combustion chamber 11 are connected to the chamber of the furnace body 1 and wherein a fan is installed in the exhaust opening 13 of the furnace body 1, or wherein the measuring section of the moisture sensor 6 is embedded directly in the through-hole 213 in the fuel conveying channel 21, as in the . Fig. 4, Fig. 5 and Fig. 6 shown, or the induction section of the humidity sensor 6 is embedded directly in the inner wall 92 of the fuel conveying channel 21, as shown in Fig. 7 shown.

[0031] S2: The humidity sensor 6 is used for continuous monitoring of the humidity of the fuel conveying channel 21, in which the pellet fuel is stored in the feed system, so that the control unit is able to determine the spatial environment or the high or low humidity of the pellet fuel in the fuel conveying channel 21. The control unit uses an MCU chip for this purpose, and the MCU chip has a built-in program for assessing the humidity condition.

[0032] If it is determined that the spatial environment in the fuel feed channel 21 or the pellet fuel has a high moisture content, the pellet stove's control unit controls the feed system to enter a return mode, in which the pellet fuel is returned to the feed inlet 211 of the feed system (return mode in the case of the intelligent anti-blockage function), or it controls the pellet stove to enter a dry-ignition mode, or it controls the pellet stove to enter an anti-extinguishment mode; whereby the return mode may cause the motor 4, which drives the auger 22, to run in reverse while driving the auger 22 backwards to return the wet pellet fuel in the fuel feed channel 21 to its feed inlet 211, thus preventing the wet pellet fuel from drying out again and clumping, which could lead to a blockage of the fuel feed channel 21;The drying ignition mode allows the moist, particulate fuel to be transported into combustion chamber 11 in order to dry the moist, particulate fuel before ignition; and the anti-extinguishing mode allows the normal combustion flame in combustion chamber 11 not to be extinguished by the subsequent transport of the moist fuel.

[0033] If it is determined that the spatial environment or the pellet fuel in the fuel feed channel 21 has low humidity, the pellet stove control system controls the pellet stove's feed system to switch to feed mode, and in feed mode the pellet fuel can be delivered to the combustion chamber 11 as soon as the user uses the pellet stove.

[0034] Furthermore, the humidity sensor 6 uses a humidity-sensitive resistor, the resistance value being lower the higher the humidity and higher the lower the humidity. Therefore, the current spatial environment within the fuel feed channel 21 or the moisture content of the pellet fuel is high or low according to the resistance value of the humidity-sensitive resistor, and if the value of the humidity-sensitive resistor is lower than a predetermined resistance value, the pellet stove control unit judges that the current spatial environment within the fuel feed channel 21 or the pellet fuel has a high level of humidity;

[0035] If the value of the moisture-sensitive resistance is greater than the predetermined resistance value, the pellet stove control unit determines that the current spatial environment within the fuel conveying channel 21 or the pellet fuel has low humidity.

[0036] As in Fig. As shown in Figure 10, the pellet stove switches to the intelligent anti-blockage function based on the monitoring and assessment described above. If the value of the moisture-sensitive resistor is less than the predetermined resistance value, the control unit assesses whether the blockage-free return signal is in a non-zero position. The non-zero position is generally represented as "1" to identify the blockage-free return signal before entering return mode, thus ensuring that it is known whether the return has been performed in the feed system and preventing repeated returns.One of the specific ways to assess the blockage-free return indicator is: if the return indicator is in the non-zero position, it is returned to moisture monitoring; if the return indicator is in the zero position, it is put into return mode according to the high moisture situation, and the zero position is usually used to indicate "0".

[0037] Preferably, in return mode, the control unit controls the feeding system so that the material is returned at a predetermined time. The predetermined return time is 30 seconds, and when the return time has elapsed, the return indicator is set to a non-zero position, generally represented as "1". At this point, the waiting period begins, typically 5 minutes, until the end of which the moisture monitoring system is triggered. This process can be recorded before the material is returned for processing, in order to prevent repeated returns.

[0038] The monitoring of the moisture-sensitive resistance value is greater than the predetermined resistance value, so the control unit for controlling the feeding system in feeding mode sets a predetermined time for the feeding operation. The feeding operation lasts for 20 seconds. After the time has elapsed, the return signal will be placed in the zero position, which is generally designated as "0". At this point, the waiting period begins, which is usually 5 minutes. To wait for the moisture monitoring to end, the device can be used to trigger the return of material processing. Therefore, the trigger is high before the moisture monitoring, when the feeding system can be controlled to perform the return operation.

[0039] S3: To determine whether the user ignition process should be carried out, the situation of the pellet fuel at the feed inlet 211 can be checked at this time, or before the pellet fuel is switched on, to check the situation at the feed inlet 211; if dry nodules are found, manual cleaning is carried out; the assessment of the user ignition process consists of the control unit monitoring whether the electronic ignition rod 14 is performing the ignition process and recording the operating status of the electronic ignition rod 14 to facilitate the control unit's query of the assessment in the subsequent process.

[0040] If the user ignition process does not occur, the humidity monitoring is performed again and the intelligent anti-blockage function is activated;

[0041] When the user ignition process is performed, it is determined whether the blockage-free return indicator is in the non-zero position; if the blockage-free return indicator is in the non-zero position, the non-zero position is generally expressed as "1", which means that the return of material was performed before the user ignition process to control the feeding system to feed the material at a predetermined time during operation; after completion of the feeding, the ignition mode is activated, and the feeding time is set according to the desired flame condition.

[0042] If the unblocked return sign is in the zero position and the zero position is indicated by "0", this means that no return was performed before the user ignition process, and the sign is recognized and directly put into ignition mode.

[0043] As in Fig. As shown in 11, there is, among other things, a drying ignition mode and a normal ignition mode.

[0044] The drying ignition mode is activated when the value of the moisture-sensitive resistor falls below a predetermined resistance value and it is determined that the current ambient environment or the pellet fuel in the fuel feed channel 21 has a high moisture content. Once the drying ignition mode is activated, the control unit regulates the feed system to deliver the pellet fuel to the combustion chamber 11 at a predetermined time.The predetermined feeding time is 30 seconds, and after the feeding time is complete, the ignition rod in the combustion chamber 11 is switched on, and the ignition rod is ignited at a predetermined time to dry the wet pellet fuel at a predetermined time, and the ignition rod is operated for 1 minute at a predetermined time; Simultaneously, the fan operates continuously and intermittently to supply the combustion chamber 11 with air and oxygen, and then enters a waiting period of a predetermined time.The continuous and intermittent operating mode consists of the fan being switched on for 12 seconds and off for 8 seconds every 20 seconds, with a predetermined waiting period of 2 minutes. The temperature of the combustion chamber 11 is recorded to determine whether the temperature at the end of the waiting period is higher than a predetermined temperature value. The predetermined temperature value is 70°C, used to determine whether ignition is successful, thus ensuring that the moist pellet fuel in the combustion chamber 11 can be ignited and solving the problem of ignition difficulties in prior art pellet stoves.

[0045] The method for assessing whether ignition was successful is as follows: If the temperature of combustion chamber 11 is higher than the predetermined temperature value, it indicates that ignition was successful; if the temperature of combustion chamber 11 is below the predetermined temperature value, the control unit controls the feeding system to repeat the feeding operation at a predetermined time to deliver the pellet fuel into combustion chamber 11, with a predetermined feeding time of 5 seconds to fill combustion chamber 11 with dry pellet fuel, and then repeats the dry ignition mode process until successful ignition is indicated; this method allows the user to visually observe whether ignition in dry ignition mode is successful or not, with a predetermined temperature value of 70°C.

[0046] The normal ignition mode is activated when the value of the humidity-sensitive resistor is greater than the predetermined resistance value and it is determined that the current spatial environment within the fuel feed channel 21 or the pellet fuel has low humidity. After entering the normal ignition mode, the control unit controls the feed system to feed the pellet fuel into the combustion chamber 11 at a predetermined time, where the predetermined feed time is 30 seconds, and activates the electronic ignition rod 14 in the combustion chamber 11 after the feed time has ended; simultaneously, the fan operates continuously and intermittently to supply the combustion chamber 11 with air and oxygen, and then enters a waiting period of a predetermined time.The continuous and intermittent operating mode consists of the fan being switched on for 12 seconds and off for 8 seconds every 20 seconds, with a predetermined waiting time of 2 minutes, and the temperature of the combustion chamber 11 being determined to see if the temperature at the end of the waiting time is greater than a predetermined temperature value in order to determine whether the ignition is successful or not.

[0047] The method for assessing whether ignition was successful is as follows: If the temperature of combustion chamber 11 is higher than the predetermined temperature value, ignition is considered successful; if the temperature of combustion chamber 11 is lower than the predetermined temperature value, the control unit controls the feed system to perform the feed operation at a predetermined time to return the pellet fuel to combustion chamber 11; the predetermined feed time at this point is 5 seconds, and then the dry ignition mode is executed again until ignition is successful; in this way, the user can intuitively observe whether ignition is successful or not in normal ignition mode, where the predetermined temperature value is 70 °C.

[0048] S4: Assess whether the value of the moisture-sensitive resistance after successful ignition is lower than the predetermined resistance value, and the specific assessment method is as follows: If the value of the moisture-sensitive resistance is lower than the predetermined resistance value after successful ignition, it is determined that the current spatial environment or the pellet fuel in the fuel feed channel 21 has a high moisture content, and it switches directly to the anti-extinguishing mode; As in Fig.As shown in Figure 12, after entering anti-extinguishing mode, the control unit controls the feed system to supply the pellet fuel to the combustion chamber 11 at a predetermined time, the predetermined feed time being 10 seconds, and after the feed time has ended, the ignition rod in the combustion chamber 11 is switched on and the ignition work is carried out continuously and intermittently;The ignition rod is operated continuously and intermittently in such a way that the ignition rod is switched on for 10 seconds and off for 10 seconds every 20 seconds, while the fan is operated continuously and intermittently in such a way that it supplies the combustion chamber 11 with air and oxygen and then enters a waiting period of a predetermined time, and the fan is operated continuously and intermittently in such a way that the fan is switched on for 20 seconds and off for 10 seconds every 30 seconds; and the predetermined waiting period is 5 minutes, and the humidity monitoring is performed again when the waiting period ends.

[0049] If the value of the moisture-sensitive resistor is greater than a predetermined resistance value after successful ignition, it is assumed that the current spatial environment in the fuel feed channel 21 or the pellet fuel has low humidity, and the system switches directly to normal operating mode; In this operating mode, the control unit controls the feed system to deliver the pellet fuel into the combustion chamber 11 at a predetermined time, with the predetermined feed time being 8 seconds, during which the fan operates continuously and intermittently to supply the combustion chamber 11 with air and oxygen, and then enters a waiting period of a predetermined time;The fan is operated continuously and intermittently in such a way that the fan is switched on for 15 seconds and switched off for 15 seconds each of 30 seconds, the waiting period has a predetermined time of 5 minutes and the humidity monitoring is carried out again at the end of the waiting period.

[0050] In step S4, after successful ignition of combustion, the phenomenon of flame outbreak during the subsequent feeding of moist pellet fuel can be avoided, so that the original combustion efficiency and temperature can be maintained.

[0051] Finally, the temperature in the combustion chamber 11 is reported back to the control unit from the temperature detected by the temperature sensor in the combustion chamber 11.

Claims

[1] Control method for a pellet stove based on moisture detection, characterized by that it includes the following steps: S1. Switching on the pellet stove to simultaneously switch on its feed system and a humidity sensor (6) which is arranged on the feed system; S2. Using the humidity sensor (6) to continuously monitor the humidity of the fuel conveying channel (21) in which the pellet fuel was stored in the feed system, by enabling the control unit to assess the humidity level of the spatial environment or of the pellet fuel in the fuel conveying channel (21); and that, if it is determined that the spatial environment or the pellet fuel in the fuel conveying channel (21) is in a state of high humidity, the control unit of the pellet stove controls the feed system to enter a return mode, thereby returning the pellet fuel to the feed inlet (211) of the feed system, or controls the pellet stove to enter a drying ignition mode, or controls the pellet stove to enter an anti-extinguishing mode; and that, when it is determined that the spatial environment or the pellet fuel in the fuel conveying channel (21) is in a state of low humidity, the feed system of the pellet stove enters the feed mode under the control of the control unit. [2] Control method for a pellet stove based on moisture detection according to claim 1, characterized by, that the humidity sensor (6) is a humidity-sensitive resistor and the current humidity of the spatial environment or of the pellet fuel in the fuel conveying channel (21) is assessed according to the value of the humidity-sensitive resistor; and that, if the value of the moisture-sensitive resistance is less than the predetermined resistance value, the pellet stove control unit determines that the current spatial environment or the pellet fuel in the fuel conveying channel (21) has a high moisture content; and that if the value of the moisture-sensitive resistance is greater than the predetermined resistance value, the control unit of the pellet stove determines that the current spatial environment or the pellet fuel in the fuel conveying channel (21) has a low moisture content. [3] Control method for a pellet stove based on moisture detection according to claim 2, characterized by, that prior to entering return mode, an additional step is required to detect a blockage-free return signal, which includes the following: Assessing and recognizing from the control unit whether the blockage-free return indicator is in the non-zero position when the value of the moisture-sensitive resistance is less than the predetermined resistance value; Return to monitor the humidity again if the unblocked return indicator is in the non-zero position; Entering return mode according to the stock with high moisture content when the unblocked return indicator is in the zero position. [4] Control method for a pellet stove based on moisture detection according to claim 3, characterized by, that the control unit in return mode controls the feeding system so that it performs a return at a predetermined time, and that it sets the return indicator to a non-zero position when the return time is complete. [5] Control method for a pellet stove based on moisture detection according to claim 2, characterized by , that if the value of the moisture-sensitive resistor is greater than a predetermined resistance value, the control unit controls the feeding system so that it performs a feeding in feeding mode at a predetermined time, and it sets the return signal to zero when the feeding time is complete. [6] Control method for a pellet stove based on moisture detection according to claim 2, characterized by , that it further includes the following: Step S3. Assess whether a user ignition process is being performed; where, if the user ignition process is not performed, the humidity monitoring is performed again; wherein, when the user ignition process is performed, it is determined whether the unblocked return marker is in a non-zero position; wherein, If the clog-free return indicator is in a non-zero position, it means that the return was performed before the user ignition operation to control the feeding system so that it operates for feeding at a predetermined time and enters ignition mode upon completion of the feeding time; and wherein, if the clog-free return indicator is in a zero position, it means that the return was performed before the user ignition operation, and it enters ignition mode directly upon detection of the indicator. [7] Control method for a pellet stove based on moisture detection according to claim 6, characterized by, that the ignition mode includes the following: a drying ignition mode, whereby it enters this mode when the value of the moisture-sensitive resistance is less than a predetermined resistance value and it is determined that the spatial environment or the pellet fuel in the fuel conveying channel (21) is in a current state with high moisture content; wherein, after entering the drying ignition mode, the control unit controls the feed system so that it carries out the feed at a predetermined time in order to convey the pellet fuel into the combustion chamber (11), and the ignition rod in the combustion chamber (11) is opened after the feed time has ended, and the ignition rod performs the ignition at a predetermined time to carry out the drying of the wet pellet fuel, the fan operates simultaneously in a continuous and intermittent manner, to supply the combustion chamber (11) with wind and oxygen, and then enters a waiting period of a predetermined time, and after completion of the waiting period it is determined whether the temperature of the combustion chamber (11) is greater than a predetermined temperature value; wherein if the temperature of the combustion chamber (11) is greater than the predetermined temperature value, the ignition is successful; and wherein, if the temperature of the combustion chamber (11) is lower than the predetermined temperature value, the control unit controls the feed system to perform the feed at a predetermined time to refeed the pellet fuel into the combustion chamber (11) and the drying ignition mode is performed again until ignition is successful; [8] Control method for a pellet stove based on moisture detection according to claim 6, characterized by , that the ignition mode further includes the following: a normal ignition mode, whereby it enters this mode when the value of the moisture-sensitive resistance is greater than a predetermined resistance value and it is determined that the spatial environment or the pellet fuel in the fuel conveying channel (21) is in a current state with low moisture content; wherein, after entering normal ignition mode, the control unit controls the feed system so that it carries out the feed at a predetermined time to convey the pellet fuel into the combustion chamber (11), and the ignition rod in the combustion chamber (11) is opened after completion of the feed time, and the fan operates simultaneously in a continuous and intermittent manner, to supply the combustion chamber (11) with wind and oxygen, and then enters a waiting period of a predetermined time, and after completion of the waiting period it is determined whether the temperature of the combustion chamber (11) is greater than a predetermined temperature value; wherein if the temperature of the combustion chamber (11) is greater than the predetermined temperature value, the ignition is successful; and wherein, if the temperature of the combustion chamber (11) is lower than the predetermined temperature value, the control unit controls the feed system to perform the feed at a predetermined time to refeed the pellet fuel into the combustion chamber (11) and the drying ignition mode is performed again until ignition is successful. [9] Control method for a pellet stove based on moisture detection according to claim 7, characterized by , that it further includes the following: Step S4. After successful ignition, assess whether the value of the moisture-sensitive resistor is lower than the predetermined resistance value; wherein, if after successful ignition it is determined that the value of the moisture-sensitive resistance is less than the predetermined resistance value, it is determined that the spatial environment or the pellet fuel in the fuel conveying channel (21) has a high humidity, and it enters anti-deletion mode directly; where, if after successful ignition it is determined that the value of the moisture-sensitive resistance is greater than the predetermined resistance value, it is determined that the spatial environment or the pellet fuel in the fuel conveying channel (21) has a low moisture content, and it enters normal ignition mode directly; wherein, in this mode, the control unit controls the feed system so that it carries out the feed at a predetermined time to convey the pellet fuel into the combustion chamber (11), and the fan simultaneously operates in a continuous and intermittently operates to heat the combustion chamber (11) with wind and to supply oxygen, and then enters a waiting period of a predetermined time, and humidity monitoring is carried out again after the waiting period has ended. [10] Control method for a pellet stove based on moisture detection according to claim 9, characterized by, that after entering anti-extinguishing mode, the control unit controls the feed system so that it carries out the feed at a predetermined time to convey the pellet fuel into the combustion chamber (11), and after completion of the feed time, it opens the ignition rod and carries out the feed in a continuous and intermittent manner, and the fan operates in a continuous and intermittent manner to supply the combustion chamber (11) with air and oxygen, and then enters a waiting period of a predetermined time, and the monitoring of the humidity is carried out again after completion of the waiting period. [11] Feeding system for a pellet stove, characterized by , that it includes the following: a screw conveyor (2) wherein the screw conveyor (2) comprises a fuel conveying channel (21), a screw (22) arranged in the fuel conveying channel (21) and a rotary drive device for driving the rotation of the screw (22), wherein the outlet (212) of the fuel conveying channel (21) is connected to the feed opening (112) of the combustion chamber (11); a humidity sensor (6), wherein the humidity sensor (6) is arranged on a wall (9) of the fuel conveying channel (21); and a control unit, wherein the rotary drive device and the humidity sensor (6) are each connected to and controlled by the control unit; and Control method for a pellet stove based on moisture detection according to claim 1, to control the operation of the screw conveyor (2), the moisture sensor (6) and the control unit. [12] Feed system for a pellet stove according to claim 11, characterized by , that the wall (9) of the fuel conveying channel (21) comprises an outer wall (91) and a through-hole (213), the induction section of the moisture sensor (6) is arranged on the outer wall (91) and the induction section of the moisture sensor (6) is arranged in a position corresponding to the position of the through-hole (213). [13] Feed system for a pellet stove according to claim 12, characterized by , that a moisture-absorbing material (7) is arranged between the outer wall (91) and the induction section of the moisture sensor (6), and that the upper and lower side surfaces of the moisture-absorbing material (7) are each attached to the outer wall (91) and to the induction section of the moisture sensor (6), and that the moisture-absorbing material (7) covers the through-hole (213). [14] Feed system for a pellet stove according to claim 11, characterized by , that the wall (9) of the fuel conveying channel (21) comprises an inner wall (92) and a through-hole (213), and that at least a part of the moisture sensor (6) is embedded in the through-hole (213) such that the induction section of the moisture sensor (6) is flush with the inner wall (92) or the induction section of the moisture sensor (6) protrudes from the inner wall (92) or the induction section of the moisture sensor (6) is arranged in the through-hole (213). [15] Feed system for a pellet stove according to claim 11, characterized by , that the wall (9) of the fuel conveying channel (21) includes an inner wall (92), and that the moisture sensor (6) is arranged on the inner wall (92) and is in direct contact with the pellet fuel in the fuel conveying channel (21). [16] Feed system for a pellet stove according to claim 11, characterized by, that the moisture sensor (6) is located in the area between a feed inlet (211) and the outlet (212) on the fuel delivery channel (21), or that the moisture sensor (6) is located in an area of ​​the feed inlet (211) on the fuel delivery channel (21). [17] Feed system for a pellet stove according to claim 16, characterized by , that the moisture sensor (6) is located on the upper or lower side of the fuel delivery channel (21). [18] Feed system for a pellet stove according to claim 13, characterized by , that the humidity sensor (6) is attached to the outer wall (91) by means of a housing (8) and the moisture-absorbing material (7) is attached inside the housing (8).

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