Baking control method of tobacco dryer

Abstract

The present invention relates to the technical field of tobacco drying, and specifically provides a baking control method for a tobacco dryer, which aims to solve the problem that after the existing dryer is turned on, the preset value of the dry-bulb and wet-bulb temperatures in the first baking stage is relatively low, which leads to frequent opening of the fresh air vent and the dehumidification port for dehumidification, thereby reducing the baking quality of tobacco leaves with low moisture content. To this end, the baking control method of the present invention includes: controlling the dryer to enter a heating stage, and controlling the dryer not to enter a dehumidification mode during the heating stage; and at the end of the heating stage, judging whether the dryer needs to enter a dehumidification mode. The present invention sets a pre-baking stage before the dryer performs baking in the yellowing stage, and does not perform dehumidification during the heating stage of the pre-baking stage, so as to avoid the tobacco from precipitating a large amount of moisture when the moisture content is low. At the same time, at the end of the heating stage, it is judged whether dehumidification is performed. Dehumidification can remove part of the moisture, so as to avoid the moisture content in the baking room being too high to damage the tobacco.

Description

Technical Field

[0001] The invention relates to the technical field of tobacco drying, and in particular provides a baking control method of a tobacco dryer. Background Art

[0002] During the dehumidification process of tobacco drying, the heat pump tobacco dryer will compare the real-time dry-bulb and wet-bulb temperature range in the current drying room with the currently set dry-bulb and wet-bulb temperature range. If the wet-bulb temperature exceeds the set value, dehumidification will occur.

[0003] The existing traditional tobacco baking technology is generally divided into three-stage baking processes: yellowing, coloring and drying. Before baking, the tobacco leaves are put into the baking room and left to stand for 24 hours before the machine is turned on for baking. During this process, the surface of the tobacco leaves and the broken veins will emit some moisture into the baking room as the tobacco leaves themselves heat up. Since tobacco leaves are usually baked in the summer and autumn when the outside temperature is high, the dry-bulb and wet-bulb temperatures in the baking room are usually relatively high at this time. After the machine is turned on, the preset values ​​of the dry-bulb and wet-bulb temperatures in the first baking stage (the yellowing stage) are relatively low. At this time, the fresh air vents and dehumidification vents will be frequently opened for dehumidification according to the program settings. For some tobacco varieties with low moisture content, and tobacco baking in relatively arid areas, the frequent dehumidification of the dryer in the early stage of baking will cause the quality of the tobacco leaves to decline.

[0004] Therefore, the present invention needs to provide a new baking control method of a tobacco dryer to solve the above technical problems. Summary of the Invention

[0005] The present invention aims to solve the above-mentioned technical problem, that is, to solve the problem that after the existing dryer is turned on, the preset values ​​of the dry-bulb and wet-bulb temperatures in the first baking stage are relatively low. At this time, according to the program setting, the fresh air inlet and the dehumidification port will be frequently opened to perform dehumidification operations. For some tobacco varieties with low moisture content and tobacco baking in relatively arid areas, this frequent dehumidification of the dryer in the first baking stage will cause the quality of the tobacco leaves to deteriorate.

[0006] To this end, in a first aspect, the present invention provides a baking control method for a tobacco dryer, wherein the baking stage of the dryer includes a yellowing stage, and is characterized in that the baking stage of the dryer also includes a pre-baking stage, the pre-baking stage is arranged before the yellowing stage and includes a heating stage and a temperature stabilization stage, the temperature stabilization stage is divided into at least two time periods, and the baking control method includes:

[0007] controlling the dryer to enter a temperature rising stage in the pre-baking stage, and controlling the dryer not to enter a dehumidification mode during the temperature rising stage;

[0008] At the end of the heating stage, determining whether the dryer needs to enter a dehumidification mode;

[0009] After the dehumidification mode ends, the dryer is controlled to sequentially perform the temperature stabilization stage in the pre-baking stage according to at least two time periods.

[0010] When adopting the above technical solution, a pre-baking stage is set before the dryer performs baking in the yellowing stage. During the heating stage of the pre-baking stage, the dryer is set not to dehumidify, that is, the fresh air inlet and the dehumidification port of the dryer are both in a closed state, and dehumidification is not performed in response to changes in the wet-bulb temperature. This avoids the precipitation of a large amount of water from tobacco when the water content is originally low, thereby reducing the baking quality. At the same time, at the end of the heating stage, it is determined whether to dehumidify. Through dehumidification, part of the water can be removed, thereby avoiding too high a moisture content in the baking room to damage the tobacco, thereby improving the drying effect of the dryer.

[0011] In a specific embodiment of the above-mentioned tobacco drying machine baking control method, the baking control method further includes:

[0012] During each time period of the steady temperature stage, the dryer is controlled not to enter the dehumidification mode, and at the end of each time period of the steady temperature stage, it is determined whether the dryer needs to enter the dehumidification mode, and after the dehumidification mode ends, the dryer is controlled to execute the steady temperature stage of the next time period.

[0013] When adopting the above technical solution, the dryer is set not to dehumidify during the steady temperature stage of the pre-baking stage, that is, the fresh air inlet and the dehumidification port of the dryer are both in a closed state, and dehumidification is not performed in response to changes in the wet-bulb temperature, thereby avoiding the precipitation of a large amount of moisture from the tobacco when the moisture content is originally low, thereby reducing the baking quality; at the same time, after the end of each time period, it is determined whether dehumidification is performed. Dehumidification can remove part of the moisture, thereby avoiding the moisture content in the baking room being too high to damage the tobacco, thereby improving the drying effect of the dryer.

[0014] In a specific embodiment of the above-mentioned tobacco dryer baking control method, the step of "determining whether the dryer needs to enter the dehumidification mode at the end of the heating stage" further includes:

[0015] Get the current wet bulb temperature T in the oven 升 ;

[0016] Compare the current wet bulb temperature T 升 and the magnitude of the first preset wet-bulb temperature;

[0017] Based on the current wet-bulb temperature T 升 The result of comparison with the first preset wet-bulb temperature is used to selectively control whether the dryer enters a dehumidification mode.

[0018] In the specific implementation of the above tobacco drying machine baking control method, "based on the current wet-bulb temperature T升 The step of selectively controlling whether the dryer enters a dehumidification mode based on a result of comparing the temperature with a first preset wet-bulb temperature specifically includes:

[0019] If the current wet-bulb temperature T 升 is greater than or equal to a first preset wet-bulb temperature, controlling the dryer to enter a dehumidification mode; and / or

[0020] If the current wet-bulb temperature T 升 If the wet-bulb temperature is lower than the first preset wet-bulb temperature, the dryer is controlled not to enter the dehumidification mode.

[0021] When the above technical solution is adopted, the present invention determines whether dehumidification is required based on the wet-bulb temperature in the curing room at the end of the heating stage, so as to avoid excessive moisture content in the curing room that may damage the tobacco.

[0022] In a specific embodiment of the above-mentioned tobacco drying machine baking control method, the baking control method further includes:

[0023] When the dryer enters the dehumidification mode, the current wet bulb temperature T 升 and wet bulb target temperature T 目标 size;

[0024] If the current wet-bulb temperature T 升 Less than or equal to the wet bulb target temperature T 目标 , then control the dryer to exit the dehumidification mode;

[0025] If the current wet-bulb temperature T 升 Greater than the wet bulb target temperature T 目标 , the dryer is controlled to continue in the dehumidification mode.

[0026] In the case of adopting the above technical solution, when the dehumidification mode is executed at the end of the heating stage, the current wet-bulb temperature T 升 and wet bulb target temperature T 目标 The size of the dryer determines whether the dryer needs to exit the dehumidification mode. By dehumidifying, the humidity in the drying room is reduced to ensure the quality of the tobacco and avoid excessive moisture loss in the tobacco, which affects the quality of the tobacco.

[0027] In a specific embodiment of the above tobacco drying control method, the drying control method further comprises: when the dryer enters the dehumidification mode, comparing the current wet-bulb temperature T 升 and wet bulb target temperature T 目标 size;

[0028] If the current wet-bulb temperature T 升Less than or equal to the wet bulb target temperature T 目标 , then control the dryer to exit the dehumidification mode;

[0029] If the current wet-bulb temperature T 升 Greater than the wet bulb target temperature T 目标 , then when the first preset time is reached, compare the current wet-bulb temperature T 升 and the magnitude of the second preset wet-bulb temperature;

[0030] If the current wet-bulb temperature T 升 If the wet-bulb temperature is less than or equal to a second preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode;

[0031] If the current wet-bulb temperature T 升 If the wet-bulb temperature is greater than a second preset wet-bulb temperature, the dryer is controlled to continue in the dehumidification mode;

[0032] The second preset wet-bulb temperature is greater than the wet-bulb target temperature T 目标 .

[0033] In the case of adopting the above technical solution, when the dehumidification judgment is performed within the first preset time, if the current wet-bulb temperature T 升 Still greater than the wet bulb target temperature T 目标 , then compare the current wet bulb temperature T 升 The magnitude of the second preset wet bulb temperature is equal to the current wet bulb temperature T 升 When the temperature is less than or equal to the second preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode. Since the second preset wet-bulb temperature is greater than the wet-bulb target temperature T 目标 When the dehumidification reaches the first preset time, the conditions for exiting the dehumidification mode are relaxed to avoid excessive moisture loss in the tobacco due to excessive dehumidification time, which affects the quality of the tobacco. It also helps to shorten the length of the pre-baking stage and shorten the overall baking time.

[0034] In a specific embodiment of the above-mentioned tobacco dryer baking control method, the step of "determining whether the dryer needs to enter the dehumidification mode at the end of each time period in the steady temperature stage" further includes:

[0035] Get the current wet bulb temperature T in the oven 稳 ;

[0036] Compare the current wet bulb temperature T 稳 and the magnitude of the third preset wet-bulb temperature;

[0037] Based on the current wet-bulb temperature T 稳 The result of comparison with the third preset wet-bulb temperature is used to selectively control whether the dryer enters a dehumidification mode.

[0038] When adopting the above technical solution, after executing a period of temperature stabilization, the present invention determines whether dehumidification is required based on the wet-bulb temperature in the curing room to avoid excessive moisture content in the curing room that damages tobacco.

[0039] In the specific implementation of the above tobacco drying machine baking control method, "based on the current wet-bulb temperature T 稳 The step of selectively controlling whether the dryer enters a dehumidification mode based on a result of comparing the temperature with a third preset wet-bulb temperature specifically includes:

[0040] If the current wet-bulb temperature T 稳 is greater than a third preset wet-bulb temperature, controlling the dryer to enter a dehumidification mode; and / or

[0041] If the current wet-bulb temperature T 稳 If the wet-bulb temperature is less than or equal to the third preset wet-bulb temperature, the dryer is controlled not to enter the dehumidification mode.

[0042] In the case of adopting the above technical solution, during the execution of the dehumidification mode, according to the current wet-bulb temperature T 升 and wet bulb target temperature T 目标 The size of the dryer determines whether the dryer needs to exit the dehumidification mode. By dehumidifying, the humidity in the drying room is reduced to ensure the quality of the tobacco and avoid excessive moisture loss in the tobacco, which affects the quality of the tobacco.

[0043] In a specific embodiment of the above-mentioned tobacco drying machine baking control method, the baking control method further includes:

[0044] When the dryer enters the dehumidification mode, the current wet bulb temperature T 稳 and the magnitude of the third preset wet-bulb temperature and the fourth preset wet-bulb temperature;

[0045] If the current wet-bulb temperature T 稳 If the wet-bulb temperature is less than or equal to a third preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode;

[0046] If the current wet-bulb temperature T 稳 is greater than the third preset wet-bulb temperature, then when the second preset time is reached, the current wet-bulb temperature T 稳 and the magnitude of the fourth preset wet-bulb temperature;

[0047] If the current wet-bulb temperature T 稳 If the temperature is less than or equal to a fourth preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode;

[0048] If the current wet-bulb temperature T稳 If the current wet-bulb temperature is greater than the fourth preset wet-bulb temperature, the dryer is controlled to continue in the dehumidification mode until the current wet-bulb temperature T 稳 When the temperature is less than or equal to a third preset wet-bulb temperature, controlling the dryer to exit the dehumidification mode;

[0049] The fourth preset wet-bulb temperature is greater than the third preset wet-bulb temperature.

[0050] In the case of adopting the above technical solution, when the dehumidification judgment is performed within the second preset time, if the current wet-bulb temperature T 稳 If the current wet-bulb temperature is still greater than the third preset wet-bulb temperature, the current wet-bulb temperature T 稳 The magnitude of the fourth preset wet-bulb temperature is equal to the current wet-bulb temperature T 升 When the dryer is less than or equal to the fourth preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode. Since the second preset wet-bulb temperature is greater than the first preset wet-bulb temperature, when the dehumidification reaches the second preset time, the conditions for exiting the dehumidification mode are relaxed to avoid excessive moisture loss in the tobacco due to excessive dehumidification time, which affects the quality of the tobacco. It also helps to shorten the length of the pre-baking stage and shorten the overall baking time.

[0051] In a specific embodiment of the above-mentioned tobacco dryer baking control method, the baking stage of the dryer also includes a color fixing stage and a tendon drying stage. After executing the pre-baking stage, the dryer sequentially executes the yellowing stage, color fixing stage and tendon drying stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

[0053] Figure 1 This is a flow chart of the main steps of the tobacco dryer baking control method provided by the present invention;

[0054] Figure 2 yes Figure 1 Detailed step flow chart of step S2;

[0055] Figure 3 It is a detailed flowchart of step S4. DETAILED DESCRIPTION

[0056] Preferred embodiments of the present invention are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are intended only to illustrate the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art may adjust these embodiments as needed to suit specific applications.

[0057] It should be noted that, in the description of the present invention, terms such as "upper," "lower," "inner," and "outer" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. These are used solely for ease of description and are not intended to indicate or imply that the relevant devices or components must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, ordinal numbers such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0058] Furthermore, it should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted" and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; and direct or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0059] In the prior art, the dryer dehumidifies by opening and closing the fresh air inlet and the dehumidification outlet. After the dryer is turned on, the preset values ​​of the dry-bulb and wet-bulb temperatures in the first baking stage are relatively low. At this time, according to the program settings, the fresh air inlet and the dehumidification outlet will be frequently opened to perform dehumidification operations. For some tobacco varieties with low moisture content, and tobacco baking in relatively arid areas, this frequent dehumidification of the dryer in the first baking stage will cause the quality of the tobacco leaves to deteriorate.

[0060] In order to solve the above technical problems, the present invention provides a tobacco dryer, in which a wet bulb and a wet bulb temperature sensor for detecting the wet bulb temperature are installed in a drying room of the dryer. The baking stage of the dryer includes a yellowing stage, and the baking stage of the dryer also includes a pre-baking stage. The pre-baking stage is arranged before the yellowing stage. The pre-baking stage includes a heating stage and a temperature stabilization stage. The temperature stabilization stage is divided into at least two time periods.

[0061] See first Figure 1 The present invention also provides a tobacco drying machine baking control method, the baking control method comprising:

[0062] S1, controlling the dryer to enter a heating stage, and controlling the dryer not to enter a dehumidification mode during the heating stage of the pre-baking stage;

[0063] S2, at the end of the heating stage, determines whether the dryer needs to enter the dehumidification mode;

[0064] S3, after the dehumidification mode ends, controlling the dryer to sequentially perform the temperature stabilization stage in the pre-baking stage according to at least two time periods.

[0065] See Figure 3 , the baking control method further includes:

[0066] S4, during each time period of the steady temperature stage, the dryer is controlled not to enter the dehumidification mode, and at the end of each time period of the steady temperature stage, it is determined whether the dryer needs to enter the dehumidification mode, and after the dehumidification mode ends, the dryer is controlled to execute the steady temperature stage of the next time period.

[0067] It should be noted that the temperature stabilization stage is divided into at least two time periods, which can be two, three, or four, and each time period can be the same or different, depending on the baking requirements. For example, when executing the temperature stabilization stage, the two time periods are used as an example. After entering the temperature stabilization stage, the first time period is first executed. At the end of this time period, it is determined whether the dryer needs to enter the dehumidification mode. After the dehumidification mode ends, the temperature stabilization stage of the second time period is entered. After the temperature stabilization stage of the second time period is completed, the next stage can be entered. The yellowing stage is baked according to the baking process in the existing technology.

[0068] During the heating stage and the temperature stabilization stage, the dryer is controlled not to enter the dehumidification mode, which means that no matter how high the wet-bulb temperature is, the dryer will not dehumidify, that is, the dehumidification outlet and the fresh air outlet are both in the closed state.

[0069] Specifically, see Figure 2 The step S2 of “at the end of the heating stage, determining whether the dryer needs to enter the dehumidification mode” further includes:

[0070] S21, obtain the current wet bulb temperature T in the baking room 升 ;

[0071] S22, compare the current wet bulb temperature T 升 and the magnitude of the first preset wet-bulb temperature;

[0072] S23, based on the current wet bulb temperature T 升 The result of comparison with the first preset wet-bulb temperature is used to selectively control whether the dryer enters the dehumidification mode.

[0073] In the above embodiment, the current wet-bulb temperature is obtained by detecting the wet-bulb temperature information of the wet-bulb temperature sensor. 升 The result of the comparison with the first preset wet-bulb temperature determines whether dehumidification is required within the baking room. The first preset wet-bulb temperature is higher than the target wet-bulb temperature within the baking room, and the difference between the two can be between 0.5°C and 1.5°C. The target wet-bulb temperature is set based on the baking requirements of the baked goods within the baking room, and the first preset wet-bulb temperature is set based on the target wet-bulb temperature. It should be noted that the present invention does not impose specific limitations on the first preset wet-bulb temperature and the target wet-bulb temperature; design choices should be made based on actual requirements.

[0074] Continue reading Figure 2 In one embodiment, “based on the current wet bulb temperature T 升 The step S23 of "selectively controlling whether the dryer enters the dehumidification mode based on the result of comparing the temperature with the first preset wet-bulb temperature" specifically includes:

[0075] S231, if the current wet bulb temperature T 升 If the temperature is greater than or equal to the first preset wet-bulb temperature, the dryer is controlled to enter the dehumidification mode;

[0076] S232, if the current wet-bulb temperature T 升 If the wet-bulb temperature is lower than the first preset wet-bulb temperature, the dryer is controlled not to enter the dehumidification mode.

[0077] In the above embodiment, the present invention determines whether dehumidification is required based on the wet-bulb temperature in the curing barn at the end of the heating stage, so as to avoid excessive moisture content in the curing barn that may damage the tobacco.

[0078] Specifically, in the first embodiment, the baking control method further includes:

[0079] When the dryer enters dehumidification mode, compare the current wet bulb temperature T 升 and wet bulb target temperature T 目标 size;

[0080] If the current wet-bulb temperature T 升 Less than or equal to the wet bulb target temperature T 目标 , then the dryer is controlled to exit the dehumidification mode;

[0081] If the current wet-bulb temperature T 升 Greater than the wet bulb target temperature T 目标 , the dryer is controlled to continue in dehumidification mode.

[0082] At the end of the heating phase, the dehumidification mode is executed according to the current wet bulb temperature T 升 and wet bulb target temperature T 目标 The size of the dryer determines whether it needs to exit the dehumidification mode. The current wet bulb temperature T 升 Less than or equal to the wet bulb target temperature T 目标 , it means that the humidity in the curing room has not reached the dehumidification standard and does not need dehumidification. If it is greater than , it means that the humidity in the curing room is very high and needs dehumidification. By dehumidification, the humidity in the curing room can be reduced to ensure the quality of tobacco and avoid excessive loss of water in tobacco, which may affect the quality of tobacco.

[0083] In a second embodiment, the baking control method further includes:

[0084] When the dryer enters dehumidification mode, compare the current wet bulb temperature T 升 and wet bulb target temperature T 目标size;

[0085] If the current wet bulb temperature T 升 Less than or equal to the wet bulb target temperature T 目标 , then the dryer is controlled to exit the dehumidification mode;

[0086] If the current wet bulb temperature T 升 Greater than the wet bulb target temperature T 目标 , then when the first preset time is reached, compare the current wet bulb temperature T 升 and the magnitude of the second preset wet-bulb temperature;

[0087] If the current wet-bulb temperature T 升 If the temperature is less than or equal to the second preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode;

[0088] If the current wet-bulb temperature T 升 If the temperature is greater than the second preset wet-bulb temperature, the dryer is controlled to continue in the dehumidification mode;

[0089] The second preset wet-bulb temperature is greater than the wet-bulb target temperature T 目标 .

[0090] In the above embodiment, in the dehumidification mode, if the current wet-bulb temperature T detected within the first preset time is 升 Always greater than the wet bulb target temperature T 目标 , then when the first preset time is reached, the judgment condition can be relaxed, that is, the current wet-bulb temperature T 升 Whether the temperature is less than or equal to the second preset wet-bulb temperature. Since the second preset wet-bulb temperature is greater than the first preset wet-bulb temperature, the conditions for exiting the dehumidification mode are relaxed, preventing excessive moisture loss from the tobacco due to prolonged dehumidification time, which affects tobacco quality. This also helps shorten the duration of the pre-baking stage and the overall baking time. Therefore, the second embodiment is regarded as the preferred embodiment of the present invention.

[0091] It should be noted that the second preset wet-bulb temperature is based on the wet-bulb target temperature T 目标 The difference between the two can be set to 0.3℃-1℃.

[0092] In one embodiment, see Figure 3 The step S4 of “determining whether the dryer needs to enter the dehumidification mode at the end of each time period in the temperature stabilization stage” further includes:

[0093] S41, obtain the current wet-bulb temperature T in the baking room 稳 ;

[0094] S42, compare the current wet bulb temperature T稳 and the magnitude of the third preset wet-bulb temperature;

[0095] S43, based on the current wet bulb temperature T 稳 The result of comparison with the third preset wet-bulb temperature is used to selectively control whether the dryer enters the dehumidification mode.

[0096] After a period of time of temperature stabilization, the present invention determines whether dehumidification is required based on the wet-bulb temperature in the curing room to prevent the moisture content in the curing room from being too high to damage the tobacco. 目标 The difference between the two can be 0.3° C.-1° C. The present invention does not specifically limit the third preset wet-bulb temperature and is designed according to the baking process requirements.

[0097] Specifically, "based on the current wet-bulb temperature T 稳 The step of selectively controlling whether the dryer enters a dehumidification mode based on a result of comparing the temperature with a third preset wet-bulb temperature specifically includes:

[0098] S431, if the current wet bulb temperature T 稳 If the temperature is greater than the third preset wet-bulb temperature, the dryer is controlled to enter the dehumidification mode;

[0099] S432, if the current wet-bulb temperature T 稳 If the temperature is less than or equal to the third preset wet-bulb temperature, the dryer is controlled not to enter the dehumidification mode.

[0100] During the dehumidification mode, according to the current wet bulb temperature T 升 and wet bulb target temperature T 目标 The size of the dryer determines whether the dryer needs to exit the dehumidification mode. By dehumidifying, the humidity in the drying room is reduced to ensure the quality of the tobacco and avoid excessive moisture loss in the tobacco, which affects the quality of the tobacco.

[0101] Specifically, in the first embodiment, the baking control method further includes: when the dryer enters the dehumidification mode, until the current wet-bulb temperature T 稳 When the temperature is less than or equal to the third preset wet-bulb temperature, the dehumidification mode is exited.

[0102] In a second embodiment, the baking control method further includes:

[0103] When the dryer enters dehumidification mode, compare the current wet bulb temperature T 稳 and the magnitude of the third preset wet-bulb temperature and the fourth preset wet-bulb temperature;

[0104] If the current wet-bulb temperature T 稳 If the temperature is less than or equal to the third preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode;

[0105] If the current wet-bulb temperature T 稳 If the current wet-bulb temperature is greater than the third preset wet-bulb temperature, then when the second preset time is reached, the current wet-bulb temperature T 稳 and the magnitude of the fourth preset wet-bulb temperature;

[0106] If the current wet-bulb temperature T 稳 If the temperature is less than or equal to the fourth preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode;

[0107] If the current wet-bulb temperature T 稳 If the current wet-bulb temperature is greater than the fourth preset wet-bulb temperature, the dryer is controlled to continue in the dehumidification mode until the current wet-bulb temperature T 稳 When the temperature is less than or equal to the third preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode;

[0108] The fourth preset wet-bulb temperature is greater than the third preset wet-bulb temperature.

[0109] It should be noted that the fourth preset wet-bulb temperature is set according to the third preset wet-bulb temperature, and the difference between the two can be 0.2°C-0.8°C. The present invention specifically defines the fourth preset wet-bulb temperature and sets it according to the actual baking process requirements and the value of the third preset wet-bulb temperature. When the dehumidification process is carried out after the dehumidification time reaches the second preset time, the current wet-bulb temperature T 稳 The dehumidification mode is exited when the temperature is less than or equal to the third preset wet-bulb temperature instead of when the temperature is less than or equal to the fourth preset wet-bulb temperature. This is because a set detection quiet zone (for example, a detection quiet zone of 0.2°C) exists in the dryer system. This prevents the wet-bulb temperature from rising too quickly and then re-entering dehumidification after a long dehumidification cycle, thereby extending the next period to reach the third preset wet-bulb temperature, that is, extending the next period to reach dehumidification.

[0110] In the above embodiment, when the dehumidification judgment is performed within the second preset time, if the current wet-bulb temperature T 稳 If the current wet-bulb temperature is still greater than the third preset wet-bulb temperature, the current wet-bulb temperature T 稳 The magnitude of the fourth preset wet-bulb temperature is equal to the current wet-bulb temperature T 升 When the dryer is controlled to exit the dehumidification mode when the temperature is less than or equal to the fourth preset wet-bulb temperature, since the second preset wet-bulb temperature is greater than the first preset wet-bulb temperature, the conditions for exiting the dehumidification mode are relaxed when the dehumidification reaches the second preset time. This prevents excessive moisture loss in the tobacco from affecting tobacco quality due to prolonged dehumidification time. This also helps shorten the duration of the pre-baking stage and the overall baking time. Therefore, the second embodiment is considered a preferred embodiment of the present invention.

[0111] In addition, the baking stage of the dryer also includes a color fixing stage and a reinforcement drying stage. After executing the pre-baking stage, the dryer sequentially executes the yellowing stage, color fixing stage and reinforcement drying stage.

[0112] The following example uses a drying room with a dry-bulb temperature of 35°C, a wet-bulb temperature of 35°C, a stabilization time of 10 hours, a heating rate of 1°C per hour, and an ambient temperature of 30°C as an example. The heating time is 5 hours. The specific operation is as follows:

[0113] During the heating stage (5 hours), the dryer does not respond to the wet-bulb temperature, that is, it continues to heat up without dehumidification and does not enter the dehumidification mode;

[0114] At the end of the heating stage, detect the current wet bulb temperature T in the baking room. 升 , if the current wet-bulb temperature T 升 <35.8℃ (first preset wet bulb temperature), dehumidification is not performed; if the current wet bulb temperature T 升 ≥35.8℃ (the first preset wet bulb temperature), the dryer is immediately controlled to enter the dehumidification mode, the fresh air outlet and the dehumidification outlet are opened as required, and when the current wet bulb temperature T 升 Less than the wet bulb target temperature T 目标 Exit dehumidification mode, if the front wet bulb temperature T 升 Continuous> wet bulb target temperature T 目标 , then detect the current wet bulb temperature T when it reaches 5min 升 Is it ≤35.5℃ (the second preset wet bulb temperature)? If the current wet bulb temperature T 升 ≤35.5℃, the dryer is controlled to exit the dehumidification mode. If the current wet bulb temperature T 升 >35.5℃, the dryer is controlled to continue in dehumidification mode to dehumidify until the current wet-bulb temperature T 升 Until ≤35.5℃.

[0115] After the heating stage is over, and the dryer is not in dehumidification mode, that is, when the dehumidification mode is stopped, it enters the temperature stabilization stage. Take the temperature stabilization stage as an example, which includes two time periods. The first time period is 4 hours and the second time period is 6 hours. The specific operations are as follows:

[0116] During the first time period of the steady temperature phase, the dryer does not enter the dehumidification mode, regardless of the wet-bulb temperature. When the first time period is completed, the current wet-bulb temperature T is detected. 稳 And compare it with 35.5℃ (the third preset wet bulb temperature). If the current wet bulb temperature T 稳 ≤35.5℃, dehumidification is not performed. If the current wet bulb temperature T 稳>35.5℃, it is necessary to enter the dehumidification mode for dehumidification. During the dehumidification process, if the temperature continues to be >35.5℃ within 5 minutes (the second preset time), the current wet bulb temperature T is determined when 5 minutes have passed. 升 Is it ≤35.8℃ (the fourth preset wet bulb temperature)? If the current wet bulb temperature T 稳 ≤35.8℃, the dryer is controlled to exit the dehumidification mode, that is, stop dehumidification. If the current wet-bulb temperature T 稳 >35.8℃, the dryer is controlled to continue to dehumidify until the current wet-bulb temperature T 稳 When the temperature is less than or equal to 35.5℃, the dehumidification mode is exited, and then the second time period of the steady temperature stage is executed. During this time period, the dryer does not enter the dehumidification mode. After the execution is completed, normal baking is carried out according to the baking process of the yellowing stage of the existing dryer.

[0117] In addition, the present invention also provides a tobacco dryer, comprising a controller, wherein the controller is configured to be able to execute the tobacco dryer baking control method of any one of the above technical solutions.

[0118] When adopting the above-mentioned embodiments and various expanded implementation methods, a pre-baking stage is set before the dryer performs baking in the yellowing stage. During the heating and stabilizing stages of the pre-baking stage, the dryer is set not to dehumidify, that is, the fresh air inlet and the dehumidification port of the dryer are both in a closed state, and dehumidification is not performed following the change of the wet-bulb temperature, thereby avoiding the precipitation of a large amount of water from the tobacco when the moisture content is originally low, thereby reducing the baking quality; at the same time, the judgment of whether to dehumidify is set between heating and stabilizing the temperature and between adjacent time periods. Dehumidification can remove part of the moisture, thereby avoiding too high a moisture content in the baking room to damage the tobacco, thereby improving the drying effect of the dryer.

[0119] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A tobacco drying control method for a tobacco drying machine, wherein the drying stage of the drying machine includes a yellowing stage, characterized in that: The baking stage of the dryer further includes a pre-baking stage, which is arranged before the yellowing stage and includes a heating stage and a temperature stabilization stage, and the temperature stabilization stage is divided into at least two time periods. The baking control method includes: controlling the dryer to enter the heating stage, and controlling the dryer not to enter the dehumidification mode during the heating stage; At the end of the heating stage, determining whether the dryer needs to enter a dehumidification mode; After the dehumidification mode ends, controlling the dryer to sequentially perform the temperature stabilization stage in the pre-baking stage according to at least two time periods; The baking control method further includes: During each time period of the steady temperature stage, the dryer is controlled not to enter the dehumidification mode, and at the end of each time period of the steady temperature stage, it is determined whether the dryer needs to enter the dehumidification mode, and after the dehumidification mode ends, the dryer is controlled to execute the steady temperature stage of the next time period.

2. The tobacco drying machine baking control method according to claim 1, characterized in that: The step of “determining whether the dryer needs to enter the dehumidification mode at the end of the heating stage” further includes: Get the current wet bulb temperature T in the oven 升 ; Compare the current wet bulb temperature T 升 and the magnitude of the first preset wet-bulb temperature; Based on the current wet-bulb temperature T 升 The result of comparison with the first preset wet-bulb temperature is used to selectively control whether the dryer enters a dehumidification mode.

3. The tobacco drying control method according to claim 2, characterized in that: "Based on the current wet bulb temperature T 升 The step of selectively controlling whether the dryer enters a dehumidification mode based on a result of comparing the temperature with a first preset wet-bulb temperature specifically includes: If the current wet-bulb temperature T 升 is greater than or equal to a first preset wet-bulb temperature, controlling the dryer to enter a dehumidification mode; and / or If the current wet-bulb temperature T 升 If the wet-bulb temperature is lower than the first preset wet-bulb temperature, the dryer is controlled not to enter the dehumidification mode.

4. The tobacco drying machine baking control method according to claim 3, characterized in that: The baking control method further includes: When the dryer enters the dehumidification mode, the current wet bulb temperature T 升 and wet bulb target temperature T 目标 size; If the current wet-bulb temperature T 升 Less than or equal to the wet bulb target temperature T 目标 , then control the dryer to exit the dehumidification mode; If the current wet-bulb temperature T 升 Greater than the wet bulb target temperature T 目标 , the dryer is controlled to continue in the dehumidification mode.

5. The tobacco drying machine baking control method according to claim 3, characterized in that: The baking control method further includes: When the dryer enters the dehumidification mode, the current wet bulb temperature T 升 and wet bulb target temperature T 目标 size; If the current wet-bulb temperature T 升 Less than or equal to the wet bulb target temperature T 目标 , then control the dryer to exit the dehumidification mode; If the current wet-bulb temperature T 升 Greater than the wet bulb target temperature T 目标 , then when the first preset time is reached, compare the current wet-bulb temperature T 升 and the magnitude of the second preset wet-bulb temperature; If the current wet-bulb temperature T 升 If the wet-bulb temperature is less than or equal to a second preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode; If the current wet-bulb temperature T 升 If the wet-bulb temperature is greater than a second preset wet-bulb temperature, the dryer is controlled to continue in the dehumidification mode; The second preset wet-bulb temperature is greater than the wet-bulb target temperature T 目标 .

6. The tobacco drying control method according to any one of claims 2 to 5, characterized in that: The step of “determining whether the dryer needs to enter the dehumidification mode at the end of each time period in the steady temperature stage” further includes: Get the current wet bulb temperature T in the oven 稳 ; Compare the current wet bulb temperature T 稳 and the magnitude of the third preset wet-bulb temperature; Based on the current wet-bulb temperature T 稳 The result of comparison with the third preset wet-bulb temperature is used to selectively control whether the dryer enters a dehumidification mode.

7. The tobacco drying control method according to claim 6, characterized in that: "Based on the current wet bulb temperature T 稳 The step of selectively controlling whether the dryer enters a dehumidification mode based on a result of comparing the temperature with a third preset wet-bulb temperature specifically includes: If the current wet-bulb temperature T 稳 is greater than a third preset wet-bulb temperature, controlling the dryer to enter a dehumidification mode; and / or If the current wet-bulb temperature T 稳 If the wet-bulb temperature is less than or equal to the third preset wet-bulb temperature, the dryer is controlled not to enter the dehumidification mode.

8. The tobacco drying control method according to claim 7, characterized in that: The baking control method further includes: When the dryer enters the dehumidification mode, the current wet bulb temperature T 稳 and the magnitude of the third preset wet-bulb temperature and the fourth preset wet-bulb temperature; If the current wet-bulb temperature T 稳 If the wet-bulb temperature is less than or equal to a third preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode; If the current wet-bulb temperature T 稳 is greater than the third preset wet-bulb temperature, then when the second preset time is reached, the current wet-bulb temperature T 稳 and the magnitude of the fourth preset wet-bulb temperature; If the current wet-bulb temperature T 稳 If the temperature is less than or equal to a fourth preset wet-bulb temperature, the dryer is controlled to exit the dehumidification mode; If the current wet-bulb temperature T 稳 If the current wet-bulb temperature is greater than the fourth preset wet-bulb temperature, the dryer is controlled to continue in the dehumidification mode until the current wet-bulb temperature T 稳 When the temperature is less than or equal to a third preset wet-bulb temperature, controlling the dryer to exit the dehumidification mode; The fourth preset wet-bulb temperature is greater than the third preset wet-bulb temperature.

9. The tobacco drying control method according to any one of claims 1 to 5, characterized in that: The baking stage of the dryer further includes a color fixing stage and a reinforcement drying stage. After executing the pre-baking stage, the dryer sequentially executes the yellowing stage, the color fixing stage and the reinforcement drying stage.

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