Method for detecting humidity of dishwasher and control method thereof
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HISENSE HOME APPLIANCES GRP CO LTD
- Filing Date
- 2025-09-25
- Publication Date
- 2026-06-26
Smart Images
Figure CN121286984B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of dishwasher technology, and in particular to a method for detecting and controlling the humidity of a dishwasher. Background Technology
[0002] As people's living standards continue to improve, dishwashers have gradually entered ordinary households. Dishwashers greatly reduce the burden of kitchen labor and improve users' quality of life. Dishwashers can integrate washing and drying functions. Among them, the drying function is an important function of dishwashers, which can effectively prevent odors from developing on dishes after washing and prevent mold problems caused by prolonged dampness. Traditional dishwashers generally use residual heat drying or fixed time drying methods, which are difficult to guarantee drying effect.
[0003] In related technologies, an independent humidity sensor is used to detect the dryness of the dishwasher's washing chamber, and the drying process is controlled to continue or stop based on the dryness of the washing chamber. However, humidity sensors are expensive, and during use, they are in direct contact with the high-temperature steam in the washing chamber, resulting in a short lifespan and high production and operating costs for dishwashers. Summary of the Invention
[0004] In order to reduce the high production and use costs of dishwashers, this application provides a method for detecting and controlling the humidity of a dishwasher.
[0005] In some embodiments of this application, the dishwasher includes an inner tub, a water circuit assembly, a temperature detection unit, a heating device, and a control device. The inner tub has a washing chamber; the water circuit assembly is used to supply washing water to the washing chamber; the temperature detection unit is disposed in the washing chamber and is used to detect the water temperature and gas temperature of the washing water in the washing chamber; the heating device is used to provide heat to heat the washing water; and the control device is electrically connected to the temperature detection unit and the heating device and is configured to perform a humidity detection method.
[0006] The humidity detection method includes: when the dishwasher is in the washing stage, for each inlet / outlet cycle, obtaining the total energy provided by the heating device in the inlet / outlet cycle, wherein the washing stage includes at least one inlet / outlet cycle; based on the total energy and the energy efficiency coefficient, obtaining the effective energy provided by the heating device in the inlet / outlet cycle, wherein the effective energy is the energy consumed for heating and evaporating the washing water in the total energy, and the energy efficiency coefficient is the proportion of the energy consumed for heating and evaporating the washing water in the total energy, which is inversely correlated with the energy loss of the dishwasher in the inlet / outlet cycle; removing the energy consumed for heating the washing water in the effective energy, obtaining the energy consumed for evaporating the washing water in the inlet / outlet cycle; obtaining the total energy consumed for evaporating the washing water in the washing stage based on the energy consumed for evaporating the washing water in each inlet / outlet cycle, and obtaining the total amount of evaporated water in the washing chamber based on the total energy consumed for evaporating the washing water; when the dishwasher finishes the washing stage, before entering the drying stage, obtaining the saturated water vapor mass based on the gas temperature detected by the temperature detection unit, and obtaining the relative humidity in the washing chamber based on the total amount of evaporated water and the saturated water vapor mass.
[0007] Thus, in the above technical solution, when the dishwasher is in the washing stage, firstly, the total energy provided by the heating device in each inlet and outlet cycle is obtained, and based on the total energy and the matching energy efficiency coefficient, the effective energy provided by the heating device in the inlet and outlet cycle is obtained, that is, the energy consumed for heating the washing water and evaporating the washing water in the total energy; then, the energy consumed for heating the washing water in the effective energy is removed, and the energy consumed for evaporating the washing water in the inlet and outlet cycle is obtained; then, based on the energy consumed for evaporating the washing water in each inlet and outlet cycle, the total energy consumed for evaporating water in the washing stage is obtained, and the total amount of evaporated water in the washing chamber is obtained based on the total energy consumed for evaporating water; finally, when the dishwasher finishes the washing stage and before entering the drying stage, the saturated water vapor mass is obtained based on the gas temperature detected by the temperature detection unit, and the relative humidity in the washing chamber is obtained based on the total amount of evaporated water and the saturated water vapor mass. The total amount of water evaporated in the washing chamber is calculated by the principle of energy conservation. The mass of saturated water vapor is derived by combining the gas temperature in the washing chamber before entering the drying stage. The relative humidity can be obtained by using both. The dishwasher does not need to use a humidity sensor to detect the dryness of the washing chamber, which can reduce the production and use costs of the dishwasher.
[0008] In some embodiments of this application, before obtaining the effective energy provided by the heating device during the inlet and outlet cycle based on the total energy and the energy efficiency coefficient, the method further includes: obtaining the energy efficiency coefficient based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycle, wherein the energy efficiency coefficient is positively correlated with the temperature rise.
[0009] In the above technical solution, the energy efficiency coefficient is used to represent the proportion of total energy used for heating the washing water and evaporating the washing water. This allows for the rapid acquisition of the effective energy provided by the heating device during the inlet and outlet cycles. During the washing stage, there is no need to perform a complex calculation process for lost or effective energy, which simplifies the calculation process for effective energy.
[0010] In some embodiments of this application, the energy efficiency coefficient is obtained based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycle. This includes: querying a mapping table based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycle to obtain the energy efficiency coefficient. The mapping table contains the mapping relationship between the temperature rise and the energy efficiency coefficient.
[0011] In the above technical solution, the energy efficiency coefficient is obtained by querying the mapping relationship table, which is logically simple.
[0012] In some embodiments of this application, the dishwasher includes a water level detection unit for detecting the amount of washing water in the washing chamber. The effective energy is divided into two parts: first, the water temperature rise energy consumed for heating the washing water, and the water evaporation energy consumed during the inlet and outlet cycles. This includes: obtaining the water temperature rise energy consumed for heating the washing water based on the temperature rise of the washing water obtained by the temperature detection unit and the amount of washing water detected by the water level detection unit; and second, subtracting the water temperature rise energy from the effective energy to obtain the water evaporation energy consumed during the inlet and outlet cycles.
[0013] In the above technical solution, the effective energy is obtained from the water temperature rise and the amount of washing water, which is used for water heating. The calculation results of water heating energy consumption are accurate and reliable. Based on this, the accurate water evaporation energy consumption can be obtained by subtracting the water heating energy consumption from the effective energy.
[0014] In some embodiments of this application, the total energy consumption of water evaporation in the washing stage is obtained based on the energy consumption of water evaporation used for washing water evaporation in each inlet and outlet cycle, and the total amount of evaporated water in the washing chamber is obtained based on the total energy consumption of water evaporation, including: summing the energy consumption of water evaporation used for washing water evaporation in each inlet and outlet cycle to obtain the total energy consumption of water evaporation in the washing stage; and obtaining the total amount of evaporated water in the washing chamber based on the total energy consumption of water evaporation and the latent heat of vaporization constant of water.
[0015] In the above technical solution, by summing up the energy consumed by water evaporation in each water inlet and outlet cycle, the accurate total energy consumption of water evaporation in the washing stage can be obtained. Based on this, and using the total energy consumption of water evaporation and the latent heat of vaporization of water, the accurate total amount of water evaporated can be obtained.
[0016] In some embodiments of this application, obtaining the saturated water vapor mass based on the gas temperature detected by the temperature detection unit includes: obtaining the saturated vapor pressure based on the Antoni equation and the gas temperature detected by the temperature detection unit; and obtaining the saturated water vapor mass based on the saturated vapor pressure, the volume of the washing chamber, and the gas temperature detected by the temperature detection unit.
[0017] In the above technical solution, the saturated vapor pressure is calculated based on the Antoine equation and the gas temperature detected by the temperature detection unit. The saturated vapor pressure is easy to obtain and the result is accurate. Based on this, the accurate mass of saturated water vapor can be obtained based on the saturated vapor pressure, the volume of the washing chamber, and the gas temperature detected by the temperature detection unit.
[0018] In some embodiments of this application, the saturated vapor pressure is obtained based on the Antoine equation and the gas temperature detected by the temperature detection unit, including: obtaining the saturated vapor pressure based on the relationship lgP_saturated = 8.07131 - 1730.63 / (233.426 + t_temperature), where lgP_saturated is the saturated vapor pressure and t_temperature is the gas temperature detected by the temperature detection unit. The saturated water vapor mass is obtained based on the saturated vapor pressure, the volume of the washing chamber, and the gas temperature detected by the temperature detection unit, including: obtaining the saturated water vapor mass based on the relationship m_saturated = (lgP_saturated × 1000 × V × 0.018) / (8.314 × T), where m_saturated is the saturated water vapor mass, lgP_saturated is the saturated vapor pressure, V is the volume of the washing chamber, and T is the absolute temperature, T = t_temperature + 273.15 (K), where t_temperature is the gas temperature detected by the temperature detection unit.
[0019] In the above technical solutions, the saturated vapor pressure obtained based on the relationship lgP_saturated = 8.07131 - 1730.63 / (233.426 + t_temperature) has high accuracy, and the saturated water vapor mass obtained based on the relationship m_saturated = (lgP_saturated × 1000 × V × 0.018) / (8.314 × T) has high accuracy.
[0020] In some embodiments of this application, obtaining the total energy provided by the heating device during the inlet and outlet cycle includes: obtaining the total energy provided by the heating device during the inlet and outlet cycle based on the heating power and heating duration of the heating device during the inlet and outlet cycle.
[0021] In the above technical solution, the heating power of the heating device during the inlet and outlet cycle can be obtained by directly retrieving the stored power data, the heating duration of the heating device during the inlet and outlet cycle can be obtained by automatic timing by the program, and the total energy provided by the heating device during the inlet and outlet cycle is convenient, quick, and logically simple.
[0022] In some embodiments of this application, the control method for the dishwasher includes: obtaining the relative humidity in the washing chamber of the dishwasher using the aforementioned humidity detection method; and controlling heating parameters based on the relative humidity when executing a drying program, the heating parameters including heating power and / or heating duration.
[0023] Thus, in the above technical solution, the dishwasher does not need to use a humidity sensor to detect the dryness of the washing chamber, which can reduce the production and use costs of the dishwasher; when executing the drying program, the heating parameters are controlled by the obtained relative humidity, which helps to improve the drying effect while taking into account the energy consumption of the dishwasher.
[0024] In some embodiments of this application, heating parameters are controlled based on relative humidity, including: predicting the degree of dryness in the washing chamber based on relative humidity, gas temperature in the washing chamber, and heating time; and controlling heating parameters based on the degree of dryness.
[0025] In the above technical solution, the gas temperature and heating time in the washing chamber can reflect the degree of dryness in the washing chamber to a certain extent. At the same time, combined with the obtained relative humidity, the degree of dryness in the washing chamber at the next moment can be accurately predicted.
[0026] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description
[0027] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the specification, serve to explain the principles of this application.
[0028] Figure 1 A schematic diagram of the structure of a dishwasher according to an embodiment of this application is shown.
[0029] Figure 2 It shows Figure 1 The diagram shows a partial structural composition of the dishwasher.
[0030] Figure 3 A flowchart of a humidity detection method for a dishwasher according to an embodiment of this application is shown.
[0031] Figure 4 It shows Figure 3 The flowchart showing step S330 is a detailed embodiment of one example.
[0032] Figure 5 It shows Figure 3 The flowchart showing step S340 is a detailed embodiment of one example.
[0033] Figure 6 It shows Figure 3 The flowchart showing step S350 is a detailed representation of one embodiment.
[0034] Figure 7 A flowchart of a humidity detection method for a dishwasher according to another embodiment of this application is shown.
[0035] Figure 8 A flowchart of a dishwasher control method according to an embodiment of this application is shown.
[0036] The annotations in the attached figures are explained as follows:
[0037] 100. Dishwasher; 1. Shell; 2. Inner tub; 20. Washing chamber; 3. Shelf; 31. Upper shelf; 32. Lower shelf; 41. Spray arm; 42. Washing pump; 43. Water tank; 44. Water inlet valve; 45. Water flow meter; 46. Drain pump; 5. Temperature detection unit; 6. Heating device; 7. Second heating device; 8. Display; 9. Control device. Detailed Implementation
[0038] To make the objectives, implementation methods and advantages of this application clearer, the exemplary implementation methods of this application will be clearly and completely described below with reference to the accompanying drawings of the exemplary embodiments of this application. Obviously, the described exemplary embodiments are only some embodiments of this application, and not all embodiments.
[0039] It should be noted that the brief descriptions of terms in this application are only for the convenience of understanding the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise stated, these terms should be understood in their ordinary and common meaning.
[0040] In the description of this application, it should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0041] The terms "first," "second," and other ordinal numbers are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature specified with ordinal numbers such as "first" or "second" may explicitly or implicitly include one or more of that feature.
[0042] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "setup" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0043] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.
[0044] In related technologies, dishwashers suffer from high production and usage costs. This is because setting up an independent humidity sensor to detect the dryness of the dishwasher's washing chamber is expensive, and the humidity sensor is in direct contact with the high-temperature steam in the washing chamber during use, resulting in a short lifespan.
[0045] In view of this, when the dishwasher is in the washing stage, this application first obtains the total energy provided by the heating device in each inlet and outlet cycle, and based on the total energy and the matching energy efficiency coefficient, obtains the effective energy provided by the heating device in the inlet and outlet cycle, that is, the energy consumed for heating and evaporating the washing water in the total energy; then, the energy consumed for heating the washing water in the effective energy is removed, and the energy consumed for evaporating the washing water in the inlet and outlet cycle is obtained; then, based on the energy consumed for evaporating the washing water in each inlet and outlet cycle, the total energy consumed for evaporating water in the washing stage is obtained, and the total amount of evaporated water in the washing chamber is obtained based on the total energy consumed for evaporating water in the washing stage; finally, when the dishwasher finishes the washing stage and before entering the drying stage, the saturated water vapor mass is obtained based on the gas temperature detected by the temperature detection unit, and the relative humidity in the washing chamber is obtained based on the total amount of evaporated water and the saturated water vapor mass. The dishwasher does not need to use a humidity sensor to detect the dryness state in the washing chamber, which can reduce the production and use costs of the dishwasher.
[0046] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0047] Figure 1 A schematic diagram of the structure of a dishwasher according to an embodiment of this application is shown. Figure 2 It shows Figure 1 The diagram shows a partial structural composition of the dishwasher.
[0048] like Figure 1 As shown, the dishwasher 100 of this embodiment includes a housing 1, which serves as a supporting structure for the dishwasher 100 and has an internal accommodating space (not shown in the figure). The accommodating space of the housing 1 may house other component structures of the dishwasher 100, such as an inner tub, a water circuit assembly, and a circuit structure. The external shape of the housing 1 can be designed as needed, for example, it can be a hollow cuboid shape.
[0049] The shell 1 may contain an inner liner 2, which is protected by the shell 1. The inner liner 2 contains a washing chamber 20, which can hold tableware such as bowls, plates or cups and contain washing water for cleaning the tableware.
[0050] In some embodiments, a shelf 3 is provided in the washing chamber 20 for holding tableware such as bowls, plates or cups.
[0051] The number of shelves 3 can be one or more, such as Figure 1 As shown, the washing chamber 20 is provided with two shelves 3, which can be arranged vertically and horizontally, such as upper shelf 31 and lower shelf 32.
[0052] The dishwasher 100 may also include a water circuit assembly for supplying washing water to the washing chamber 20.
[0053] like Figure 1 As shown, the water system assembly may include a spray arm 41, which is used to spray washing water onto the tableware on the shelf 3 to clean the tableware on the shelf 3. The spray arm 41 may be rotatably disposed in the washing chamber 20.
[0054] In some embodiments, the spray arm 41 is a hollow housing with multiple spray holes for spraying washing water onto the tableware on the shelf 3. Figure 1 (Not shown in the image). The spray nozzles on the spray arm 41 can have different spray angles to ensure that the water flow covers tableware of different shapes such as bowls, plates, and cups.
[0055] Some of the spray holes on the spray arm 41 can be inclined to drive the spray arm 41 to rotate using the jet of water. In some embodiments, the spray arm 41 may also have a rotation drive hole for driving the spray arm 41 to rotate.
[0056] The number of spray arms 41 can be one or more, such as Figure 1As shown, a plurality of spray arms 41 are provided in the washing chamber 20. The plurality of spray arms 41 are distributed at intervals in the vertical direction of the washing chamber 20, such as an upper spray arm distributed in the upper part of the washing chamber 20, a middle spray arm distributed in the middle part of the washing chamber 20, and a lower spray arm distributed in the lower part of the washing chamber 20.
[0057] The water circuit assembly may include a washing pump 42, the outlet of which is connected to a spray arm 41 to pressurize the washing water and deliver it to the spray arm 41 so that the spray arm 41 can spray the washing water onto the tableware on the shelf 3.
[0058] The water system assembly may also include a water tank 43, which may be located at the bottom of the washing chamber 20 for holding washing water. The inlet of the washing pump 42 is connected to the water tank 43 to deliver the washing water in the water tank 43 to the spray arm 41.
[0059] Water system components may also include inlet pipes ( Figure 1 (Not shown in the image) The water inlet pipe can be connected to a water source and a water tank 43 to supply water into the water tank 43.
[0060] In some embodiments, such as Figure 2 As shown, an inlet valve 44 can be installed on the water inlet pipe. The inlet valve 44 is used to control the water intake of the dishwasher 100. When the inlet valve 44 is open, washing water can enter the washing chamber 20 through the inlet pipe. When the inlet valve 44 is closed, water intake into the washing chamber 20 stops.
[0061] In some embodiments, the dishwasher 100 may further include a water level detection unit for detecting the amount of washing water in the washing chamber 20.
[0062] like Figure 2 As shown, the water volume detection unit is a water flow meter 45. The water flow meter 45 can be installed on the water inlet pipe. The water flow meter 45 detects the amount of water delivered to the water tank 43, that is, it detects the amount of washing water entering the washing chamber 20.
[0063] The water flow meter 45 can be installed on the pipe after the water inlet of the dishwasher 100 and before the water inlet valve 44, or it can be integrated into the water inlet valve assembly. This installation position can accurately detect the amount of washing water entering the washing chamber 20, so that the control device can adjust the opening and closing of the water inlet valve 44 according to the set washing program and the flow data fed back by the water flow meter 45, so as to ensure that the dishwasher 100 can obtain an appropriate amount of washing water under different washing programs, avoiding waste caused by too much washing water or affecting the washing effect by too little washing water.
[0064] In some embodiments, such as Figure 2As shown, the water circuit assembly may also include a drain pump 46, which is used to drain residual water after washing, that is, the washing water sprayed by the spray arm 41, which can be discharged from the dishwasher 100 through the drain pump 46.
[0065] In some embodiments, such as Figure 2 As shown, the dishwasher 100 may also include a temperature detection unit 5, which is disposed in the washing chamber 20 and is used to detect the water temperature and gas temperature of the washing water in the washing chamber 20.
[0066] The temperature detection unit 5 may consist of only one temperature sensor. When the temperature detection unit 5 consists of only one temperature sensor, it may be located in the water tank 43 to detect the water temperature of the washing water in the washing chamber 20. Understandably, when the water tank 43 contains washing water, the temperature detection unit 5 detects the water temperature; when the washing water in the water tank 43 is drained, the temperature detection unit 5 detects the gas temperature in the washing chamber 20.
[0067] The temperature detection unit 5 may include multiple temperature sensors. When the temperature detection unit 5 includes multiple temperature sensors, the multiple temperature sensors may be partially located in the water tank 43 and partially located outside the water tank 43. The temperature sensor located in the water tank 43 detects the water temperature of the washing water in the washing chamber 20, and the temperature sensor located outside the water tank 43 detects the gas temperature in the washing chamber 20.
[0068] When multiple temperature sensors are installed in the water tank 43, the water temperature of the washing water in the washing chamber 20 can be obtained based on the water temperature data detected by the multiple temperature sensors. For example, the average value of the water temperature data detected by the multiple temperature sensors can be taken to obtain the water temperature of the washing water in the washing chamber 20.
[0069] When multiple temperature sensors are installed outside the water tank 43, the gas temperature in the washing chamber 20 can be obtained based on the temperature data detected by these multiple temperature sensors. For example, the average value of the temperature data detected by these multiple temperature sensors can be used to obtain the gas temperature in the washing chamber 20.
[0070] In some embodiments, the temperature detection unit 5 includes only one temperature sensor, which is set in the water tank 43. The water temperature and gas temperature in the washing chamber 20 are detected by the single temperature sensor, which helps to save on the hardware cost of the dishwasher 100.
[0071] In some embodiments, such as Figure 2As shown, the dishwasher 100 may also include a heating device 6, which provides heat to heat the washing water to improve the washing effect. The heating device 6 may be a resistance heating device. The heating device 6 is disposed in the washing chamber 20, or it may be disposed in the water tank 43. Because the heating device 6 is immersed in the washing water, it is less likely to burn out when it is activated.
[0072] Of course, the heating device 6 is not limited to a resistance heating device. Understandably, when the heating device 6 adopts other types of heating devices, the heating device 6 can be set in a location other than the water tank 43, and the appropriate setting location can be selected according to the type of heating device.
[0073] In some embodiments, the heating device 6 can be used to heat the gas in the washing chamber 20 simultaneously, thereby drying the washing chamber 20 and the tableware in the washing chamber 20.
[0074] In some embodiments, the heating device 6 may be used only to heat the washing water, while the gas in the washing chamber 20 may be heated by a separate heating device.
[0075] like Figure 2 As shown, the dishwasher 100 may further include a second heating device 7, which provides heat to heat the gas in the washing chamber 20, thereby drying the washing chamber 20 and the dishes in the washing chamber 20. The second heating device 7 may be located at the top of the inner tub 2.
[0076] In some embodiments, the dishwasher 100 may also include a fan assembly ( Figure 1 (Not shown in the image) The fan assembly is used to accelerate the flow of heat generated by the second heating device 7 in the washing chamber 20, thereby speeding up the drying of the washing chamber 20 and the tableware in the washing chamber 20, so as to improve the user experience.
[0077] In some embodiments, such as Figure 2 As shown, the dishwasher may also include a display 8, which can be a liquid crystal display (LCD) or an organic light-emitting diode (OLED) display. The specific type, size, and resolution of the display 8 are not limited. The display 8 can be used to display the control panel of the dishwasher 100. The dishwasher 100 can use the display 8 to provide feedback on its current operating status, such as running time and the rotation speed of the spray arm 41.
[0078] In some embodiments, the dishwasher 100 further includes a control device 9, which is the control center of the dishwasher 100. It connects various parts of the dishwasher 100 using various interfaces and lines, and executes various washing programs of the dishwasher 100 by running or executing programs stored in the memory and calling data stored in the memory.
[0079] In some embodiments, the control device 9 refers to a device that can generate operation control signals based on instruction opcodes and timing signals, instructing the washing pump 42 and other devices to execute control instructions. Exemplarily, the control device 9 can be a central processing unit (CPU), a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The control device 9 can also be other devices with processing functions, such as circuits, devices, or software modules; this application embodiment does not impose any limitations on this.
[0080] The control device 9 can be electrically connected to the washing pump 42, and can send control signals to the washing pump 42 to control its start-up to pump washing water to the spray arm 41, or to control the washing pump 42 to stop operating and stop pumping washing water to the spray arm 41. The control device 9 can also be electrically connected to the heating device 6, and can control its start-up and stop-down, enabling the heating device 6 to start when washing water needs to be heated and to stop at other times. The control device 9 can also be electrically connected to the second heating device 7, and can control its start-up and stop-down, enabling the second heating device 7 to start when the gas in the washing chamber 20 needs to be heated and to stop at other times. The control device 9 can be electrically connected to the temperature detection unit 5 and the water flow meter 45 (water volume detection unit). It can receive the temperature signal input from the temperature detection unit 5 and perform relevant calculations and analyses based on the temperature signal input from the temperature detection unit 5. It can also receive the washing water inlet volume input from the water flow meter 45 and control the start and stop of the water inlet valve 44 and perform relevant calculations and analyses based on the washing water inlet volume input from the water flow meter 45. The control device 9 can also be electrically connected to other structures of the dishwasher 100, such as the drain pump 46 and the display 8.
[0081] Figure 3 A flowchart of a humidity detection method for a dishwasher according to an embodiment of this application is shown.
[0082] Control device 9 is configured to perform humidity detection methods, such as Figure 3As shown, the humidity detection method includes at least steps S310 to S350, which are described in detail below:
[0083] In step S310, when the dishwasher is in the washing stage, the total energy provided by the heating device in each inlet and outlet cycle is obtained.
[0084] Understandably, the water inlet and drain cycle refers to the complete process of a dishwasher completing one "water inlet-circulation washing-draining" cycle. That is, a water inlet and drain cycle includes the complete process of water entering the washing chamber, circulating the water, and then draining the water. Only after the water is drained will the next new water inlet and drain cycle begin.
[0085] The washing phase includes at least one inlet and outlet drainage cycle.
[0086] Understandably, the washing phase includes at least one inlet / drain cycle, or it may include only one inlet / drain cycle or multiple inlet / drain cycles.
[0087] The number of inlet and outlet cycles included in the washing stage can depend on the cleaning requirements. For example, when there are more dishes in the washing chamber, the number of inlet and outlet cycles included in the washing stage is greater, and when there are fewer dishes in the washing chamber, the number of inlet and outlet cycles included in the washing stage is less. For another example, when the cleanliness requirement is high, the number of inlet and outlet cycles included in the washing stage is greater, and vice versa.
[0088] In some embodiments, the washing phase includes two inlet / outlet cycles. In some embodiments, the washing phase includes three inlet / outlet cycles. In some embodiments, the washing phase includes four inlet / outlet cycles.
[0089] In some embodiments, obtaining the total energy provided by the heating device during the inlet and outlet cycle includes: obtaining the total energy provided by the heating device during the inlet and outlet cycle based on the heating power and heating duration of the heating device during the inlet and outlet cycle.
[0090] Specifically, based on the heating power and heating duration of the heating device during the inlet and outlet cycle, the total energy provided by the heating device during the inlet and outlet cycle is obtained, including: multiplying the heating power and heating duration of the heating device during the inlet and outlet cycle, and using the product as the total energy provided by the heating device during the inlet and outlet cycle.
[0091] The heating power of the heating device during the inlet and outlet cycle can be obtained by directly retrieving the stored power data. The heating duration of the heating device during the inlet and outlet cycle can be obtained by automatic timing through the program. The total energy provided by the heating device during the inlet and outlet cycle is easy and quick to obtain, and the logic is simple.
[0092] In step S320, the effective energy provided by the heating device during the water inlet and outlet cycle is obtained based on the total energy and the energy efficiency coefficient.
[0093] Among them, effective energy is the energy consumed in the total energy used for heating the washing water and for evaporating the washing water.
[0094] When the heating device heats the water, in addition to the heat absorption and evaporation of the washing water, some energy is lost due to heat dissipation from the washing chamber, heat absorption by the tableware, and heat absorption by the inner tank. According to the principle of energy conservation, the total energy provided can be divided into two parts: effective energy and lost energy. The effective energy is used for the heat absorption and evaporation of the washing water, while the lost energy is used for heat dissipation from the washing chamber, heat absorption by the tableware, and heat absorption by the inner tank. Therefore, the total energy provided by the heating device during the water inlet and outlet cycle is equal to the sum of the effective energy and the lost energy.
[0095] When calculating the amount of water evaporated in the washing chamber, the energy loss is first eliminated, and the effective energy is calculated. The calculation is then based on the effective energy to ensure the accuracy of the water evaporation calculation results.
[0096] The energy efficiency coefficient (EEC) is the proportion of total energy used for heating and evaporating the washing water. It is inversely correlated with the energy loss during the dishwasher's inlet and outlet cycles. In other words, the lower the energy loss during the inlet and outlet cycles, the higher the EEC; conversely, the higher the energy loss, the lower the EEC.
[0097] The energy efficiency coefficient can be obtained through prior experiments. In some embodiments, a fixed amount of water is supplied to the washing chamber, and the washing water is heated from room temperature using the same heating power. The energy efficiency coefficient is obtained based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycles. The energy efficiency coefficient is positively correlated with the temperature rise.
[0098] The preset time can be a short time value that is convenient for experimental setup, such as 3 minutes or 4 minutes. The room temperature can be 25℃, etc.
[0099] By obtaining the energy efficiency coefficient through preliminary experiments, and using the energy efficiency coefficient to represent the proportion of total energy used for heating and evaporating the washing water, the effective energy provided by the heating device during the inlet and outlet cycles can be quickly obtained. During the washing stage, there is no need to perform a complex calculation process for lost or effective energy, which simplifies the calculation process for effective energy.
[0100] Understandably, the energy efficiency coefficient is a value greater than 0 and less than 1.
[0101] In some embodiments, the energy efficiency coefficient is obtained based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycle, and a mapping table is constructed, which contains the mapping relationship between the temperature rise and the energy efficiency coefficient.
[0102] For example, the constructed mapping relationship table is shown in Table 1 below:
[0103] Table 1
[0104] The temperature difference ΔT between water and room temperature per unit time effective coefficient <＝10℃ 0.6 <＝20℃ 0.73 <＝30℃ 0.82
[0105] In some embodiments, the energy efficiency coefficient is obtained based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycle, including: querying a mapping table based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycle to obtain the energy efficiency coefficient.
[0106] The energy efficiency coefficient can be obtained by querying the mapping table; the logic is simple.
[0107] In some embodiments, obtaining the effective energy provided by the heating device during the water inlet and water outlet cycle based on the total energy and the energy efficiency coefficient includes: multiplying the total energy and the energy efficiency coefficient, and using the product as the effective energy provided by the heating device during the water inlet and water outlet cycle.
[0108] In step S330, the energy consumed for heating the washing water is removed from the effective energy, and the energy consumed for evaporation of the washing water during the inlet and outlet cycle is obtained.
[0109] Effective energy is the energy consumed for heating and evaporating the washing water out of the total energy. After removing the energy consumed for heating the washing water from the effective energy, the remaining energy is the energy consumed for evaporating the washing water.
[0110] In some embodiments, such as Figure 4 As shown, the effective energy is obtained by removing the water heating energy consumed for heating the washing water from the effective energy, and obtaining the water evaporation energy consumed for evaporation of the washing water during the inlet and outlet cycles. This includes steps S410 to S420, which are described in detail below:
[0111] In step S410, the effective energy used for heating the washing water is obtained from the temperature rise of the washing water obtained by the temperature detection unit and the water volume of the washing water detected by the water volume detection unit.
[0112] In some embodiments, the energy consumed for heating the washing water is obtained from the effective energy based on the relationship Q1=m×4.2×ΔT, where Q1 is the energy consumed for heating the washing water, m is the amount of washing water detected by the water volume detection unit, ΔT is the temperature rise of the washing water obtained by the temperature detection unit, and 4.2 is the specific heat capacity of the washing water.
[0113] In step S420, the effective energy is subtracted from the energy consumed by water heating to obtain the energy consumed by water evaporation during the water inlet and outlet cycle.
[0114] exist Figure 4 In the embodiment shown, the energy consumption for heating the washing water is obtained from the effective energy based on the water temperature rise and the amount of washing water. The calculation result of the water heating energy consumption is accurate and reliable. Based on this, the accurate water evaporation energy consumption can be obtained by subtracting the water heating energy consumption from the effective energy.
[0115] In step S340, the total energy consumption of water evaporation in the washing stage is obtained based on the energy consumption of water evaporation used for washing water evaporation in each water inlet and outlet cycle, and the total amount of evaporated water in the washing chamber is obtained based on the total energy consumption of water evaporation.
[0116] When the washing stage includes multiple inlet and outlet cycles, it is necessary to combine the water evaporation energy consumed for washing water evaporation in the multiple inlet and outlet cycles to obtain the total water evaporation energy consumption of the entire washing stage. In step S340, the total water evaporation energy consumption of the washing stage is obtained based on the water evaporation energy consumed for washing water evaporation in each inlet and outlet cycle, that is, the total water evaporation energy consumption of the entire washing stage is obtained based on the water evaporation energy consumed for washing water evaporation in the multiple inlet and outlet cycles.
[0117] When the washing stage includes only one inlet and outlet cycle, the energy consumed by water evaporation for washing water evaporation in that one inlet and outlet cycle is the total energy consumed by water evaporation in the washing stage. In step S340, the total energy consumed by water evaporation in the washing stage is obtained based on the energy consumed by water evaporation for washing water evaporation in each inlet and outlet cycle. That is, the energy consumed by water evaporation for washing water evaporation in that one inlet and outlet cycle is taken as the total energy consumed by water evaporation in the entire washing stage.
[0118] In some embodiments, such as Figure 5 As shown, the total energy consumption of water evaporation in the washing stage is obtained based on the energy consumption of water evaporation for washing water evaporation in each inlet and outlet cycle, and the total amount of evaporated water in the washing chamber is obtained based on the total energy consumption of water evaporation, including steps S510 to S520, which are described in detail below:
[0119] In step S510, the energy consumption of water evaporation used for washing water evaporation in each water inlet and outlet cycle is summed to obtain the total energy consumption of water evaporation in the washing stage.
[0120] In step S520, the total amount of water evaporated in the washing chamber is obtained based on the total energy consumption of water evaporation and the latent heat of vaporization of water.
[0121] In some embodiments, the total amount of water evaporated in the washing chamber is obtained based on the relationship m_evaporation = Q2 / 2260, where m_evaporation is the total amount of water evaporated in the washing chamber, Q2 is the total energy consumed by water evaporation, and 2260 is the latent heat of vaporization constant of water.
[0122] exist Figure 5 In the embodiment shown, by summing up the energy consumed by water evaporation in each water inlet and outlet cycle, the accurate total energy consumption of water evaporation in the washing stage can be obtained. Based on this, the accurate total amount of water evaporated can be obtained according to the total energy consumption of water evaporation and the latent heat of vaporization of water.
[0123] In step S350, when the dishwasher finishes the washing stage and before entering the drying stage, the saturated water vapor mass is obtained based on the gas temperature detected by the temperature detection unit, and the relative humidity in the washing chamber is obtained based on the total evaporated water volume and the saturated water vapor mass.
[0124] Understandably, the dishwasher finishes its washing cycle when it has completed its final drainage.
[0125] Dishwashers typically include a washing stage and a drying stage. After the washing stage ends, the drying stage begins to dry the washing chamber and the dishes inside. Before entering the drying stage in step S350, that is, after the dishwasher has completed its final drainage, the heating device has not yet been turned on to heat the gas in the washing chamber.
[0126] In some embodiments, such as Figure 6 As shown, the saturated water vapor mass is obtained based on the gas temperature detected by the temperature detection unit, including steps S610 to S620, which are described in detail below:
[0127] In step S610, the saturated vapor pressure is obtained based on the Antoni equation and the gas temperature detected by the temperature detection unit.
[0128] In some embodiments, the saturated vapor pressure is obtained based on the relationship lgP_saturated = 8.07131 - 1730.63 / (233.426 + t_temperature), where lg P_saturated is the saturated vapor pressure and t_temperature is the gas temperature detected by the temperature detection unit.
[0129] In step S620, the saturated water vapor mass is obtained based on the saturated vapor pressure, the volume of the washing chamber, and the gas temperature detected by the temperature detection unit.
[0130] In some embodiments, the saturated water vapor mass is obtained based on the relationship m_saturated = (IgP_saturated × 1000 × V × 0.018) / (8.314 × T), where m_saturated is the saturated water vapor mass, lgP_saturated is the saturated vapor pressure, V is the volume of the washing chamber, and T is the absolute temperature, T = t_temperature + 273.15 (K), where t_temperature is the gas temperature detected by the temperature detection unit.
[0131] exist Figure 6 In the illustrated embodiment, the saturated vapor pressure is calculated based on the Antoni equation and the gas temperature detected by the temperature detection unit. The saturated vapor pressure is easy to obtain and the result is accurate. Based on this, the accurate mass of saturated water vapor can be obtained based on the saturated vapor pressure, the volume of the washing chamber, and the gas temperature detected by the temperature detection unit.
[0132] In some embodiments, the relative humidity in the washing chamber is obtained based on the total evaporation water volume and the saturated water vapor mass, including: obtaining the relative humidity in the washing chamber based on the relationship RH=(mevaporation / msaturation)×100%, where RH is the relative humidity in the washing chamber, mevaporation is the total evaporation water volume in the washing chamber, and msaturation is the saturated water vapor mass.
[0133] exist Figure 3 In the illustrated embodiment, when the dishwasher is in the washing stage, firstly, the total energy provided by the heating device in each inlet / outlet cycle is obtained. Based on the total energy and the matching energy efficiency coefficient, the effective energy provided by the heating device in the inlet / outlet cycle is obtained, which is the energy consumed for heating and evaporating the washing water. Then, the energy consumed for heating the washing water is removed from the effective energy, yielding the energy consumed for evaporating the washing water in the inlet / outlet cycle. Next, the total energy consumed for evaporating the washing water in the washing stage is obtained based on the energy consumed for evaporating the washing water in each inlet / outlet cycle, and the total amount of evaporated water in the washing chamber is obtained based on this total energy consumption. Finally, when the dishwasher finishes the washing stage and before entering the drying stage, the saturated water vapor mass is obtained based on the gas temperature detected by the temperature detection unit, and the relative humidity in the washing chamber is obtained based on the total amount of evaporated water and the saturated water vapor mass. By calculating the total amount of evaporated water in the washing chamber using the principle of energy conservation, and deriving the saturated water vapor mass from the gas temperature in the washing chamber before entering the drying stage, the relative humidity can be obtained using both. This eliminates the need for a humidity sensor to detect the dryness of the washing chamber, reducing the production and operating costs of the dishwasher.
[0134] Figure 7 A flowchart of a humidity detection method for a dishwasher according to another embodiment of this application is shown, as follows: Figure 7 As shown, the humidity detection method includes at least steps S710 to S770, which are described in detail below:
[0135] In step S710, when the dishwasher is in the washing stage, for each inlet and outlet cycle, the total energy provided by the heating device in the inlet and outlet cycle is obtained based on the heating power and heating duration of the heating device in the inlet and outlet cycle.
[0136] In step S720, the effective energy provided by the heating device during the inlet and outlet cycle is obtained based on the total energy provided by the heating device during the inlet and outlet cycle and the energy efficiency coefficient.
[0137] The effective energy refers to the energy consumed for heating and evaporating the washing water out of the total energy. The energy efficiency coefficient is the proportion of the total energy consumed for heating and evaporating the washing water, and it is inversely correlated with the energy loss of the dishwasher during the inlet and outlet cycles.
[0138] In step S730, the effective energy is obtained from the effective energy of ...
[0139] In step S740, the energy consumption of water evaporation used for washing water evaporation in each water inlet and outlet cycle is summed to obtain the total energy consumption of water evaporation in the washing stage.
[0140] In step S750, the total amount of water evaporated in the washing chamber is obtained based on the total energy consumption of water evaporation and the latent heat of vaporization of water.
[0141] In step S760, when the dishwasher finishes the washing stage and before entering the drying stage, the saturated vapor pressure is obtained based on the Antoni equation and the gas temperature detected by the temperature detection unit, and the saturated water vapor mass is obtained based on the saturated vapor pressure, the volume of the washing chamber and the gas temperature detected by the temperature detection unit.
[0142] In step S770, the relative humidity in the washing chamber is obtained based on the total amount of evaporated water and the mass of saturated water vapor.
[0143] After obtaining the relative humidity in the washing chamber, the drying process of the dishwasher can be optimized based on the relative humidity in the washing chamber during the drying stage.
[0144] Figure 8 A flowchart illustrating a control method for a dishwasher according to an embodiment of this application is shown. This control method can be executed by a control device 9. Figure 8 As shown, the control method includes at least steps S810 to S820, which are described in detail below:
[0145] In step S810, the relative humidity in the washing chamber of the dishwasher is obtained using the aforementioned humidity detection method.
[0146] In step S820, when the drying process is executed, the heating parameters are controlled based on the relative humidity.
[0147] The heating parameters may include heating power, heating time, or both heating power and heating time.
[0148] In some embodiments, controlling heating parameters based on relative humidity includes: predicting the degree of dryness in the washing chamber based on relative humidity, gas temperature in the washing chamber, and heating time; and controlling heating parameters based on the degree of dryness.
[0149] Specifically, intelligent models can be used to predict the dryness of the washing chamber. By inputting relative humidity, gas temperature in the washing chamber, and heating time into the intelligent model, the intelligent model can output the dryness of the washing chamber at the current moment, thus replacing humidity sensors in detecting humidity.
[0150] exist Figure 8 In the embodiment shown, the dishwasher does not need to use a humidity sensor to detect the dryness of the washing chamber, which can reduce the production and use costs of the dishwasher; when executing the drying program, the heating parameters are controlled by the obtained relative humidity, which helps to improve the drying effect while taking into account the energy consumption of the dishwasher.
[0151] Understandably, in embodiments where the dishwasher includes a second heating device, controlling the heating parameters based on relative humidity in step S820 can be based on controlling the heating parameters of the second heating device based on relative humidity. In embodiments where the dishwasher does not have a second heating device, controlling the heating parameters based on relative humidity in step S820 can be based on controlling the heating parameters of the heating device based on relative humidity.
[0152] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of this application is limited only by the appended claims.
Claims
1. A method for detecting humidity in a dishwasher, characterized in that, The dishwasher includes: The inner liner has a washing chamber; Water circuit assembly for supplying washing water to the washing chamber; A temperature detection unit is installed in the washing chamber to detect the water temperature and gas temperature of the washing water in the washing chamber. A heating device used to provide heat to heat the washing water; A control device, electrically connected to the temperature detection unit and the heating device, is configured to execute a humidity detection method, the humidity detection method comprising: When the dishwasher is in the washing phase, for each inlet and outlet cycle, the total energy provided by the heating device in the inlet and outlet cycle is obtained, wherein the washing phase includes at least one inlet and outlet cycle; Based on the total energy and the energy efficiency coefficient, the effective energy provided by the heating device in the inlet and outlet cycle is obtained, wherein the effective energy is the energy consumed for heating the washing water and evaporating the washing water in the total energy, and the energy efficiency coefficient is the proportion of the total energy consumed for heating the washing water and evaporating the washing water, which is inversely correlated with the energy loss of the dishwasher in the inlet and outlet cycle; Remove the energy consumed for heating the washing water from the effective energy, and obtain the energy consumed for evaporation of the washing water during the inlet and outlet cycle. The total energy consumption of water evaporation in the washing stage is obtained based on the energy consumption of water evaporation for washing water evaporation in each of the aforementioned water inlet and outlet cycles, and the total amount of evaporated water in the washing chamber is obtained based on the total energy consumption of water evaporation. When the dishwasher finishes the washing stage and before entering the drying stage, the saturated water vapor mass is obtained based on the gas temperature detected by the temperature detection unit, and the relative humidity in the washing chamber is obtained based on the total evaporated water volume and the saturated water vapor mass.
2. The humidity detection method according to claim 1, characterized in that, Before obtaining the effective energy provided by the heating device during the inlet and outlet cycles based on the total energy and energy efficiency coefficient, the method further includes: Based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycle, an energy efficiency coefficient is obtained, wherein the energy efficiency coefficient is positively correlated with the temperature rise.
3. The humidity detection method according to claim 2, characterized in that, The method of obtaining the energy efficiency coefficient based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycle includes: Based on the temperature rise of the washing water in the washing chamber within a preset time during the inlet and outlet cycle, a mapping relationship table is consulted to obtain the energy efficiency coefficient. The mapping relationship table contains the mapping relationship between the temperature rise and the energy efficiency coefficient.
4. The humidity detection method according to claim 1, characterized in that, The dishwasher includes a water level detection unit for detecting the amount of washing water in the washing chamber; removing the water heating energy consumed for heating the washing water from the effective energy, and obtaining the water evaporation energy consumed for evaporation of the washing water during the inlet and outlet cycle, includes: Based on the temperature rise of the washing water obtained by the temperature detection unit and the volume of the washing water detected by the water volume detection unit, the energy consumption for heating the washing water in the effective energy is obtained. Subtracting the energy consumed by water heating from the effective energy yields the energy consumed by water evaporation during the water inlet and outlet cycles.
5. The humidity detection method according to claim 1, characterized in that, The method of obtaining the total energy consumption of water evaporation in the washing stage based on the energy consumption of water evaporation for washing water evaporation in each of the inlet and outlet cycles, and obtaining the total amount of evaporated water in the washing chamber based on the total energy consumption of water evaporation, includes: The total energy consumption of water evaporation in the washing stage is obtained by summing up the energy consumption of water evaporation used for washing water evaporation in each of the water inlet and drainage cycles. Based on the total energy consumption of water evaporation and the latent heat of vaporization of water, the total amount of water evaporated in the washing chamber is obtained.
6. The humidity detection method according to claim 1, characterized in that, The process of obtaining the saturated water vapor mass based on the gas temperature detected by the temperature detection unit includes: The saturated vapor pressure is obtained based on the Antoni equation and the gas temperature detected by the temperature detection unit. The saturated water vapor mass is obtained based on the saturated vapor pressure, the volume of the washing chamber, and the gas temperature detected by the temperature detection unit.
7. The humidity detection method according to claim 6, characterized in that, The process of obtaining the saturated vapor pressure based on the Antoine equation and the gas temperature detected by the temperature detection unit includes: Based on the relationship lgP_saturated = 8.07131 - 1730.63 / (233.426 + t_temperature), the saturated vapor pressure is obtained, where lgP_saturated is the saturated vapor pressure and t_temperature is the gas temperature detected by the temperature detection unit. The process of obtaining the saturated water vapor mass based on the saturated vapor pressure, the volume of the washing chamber, and the gas temperature detected by the temperature detection unit includes: Based on the relationship m_saturated = (lgP_saturated × 1000 × V × 0.018) / (8.314 × T), the mass of saturated water vapor is obtained, where m_saturated is the mass of saturated water vapor, lgP_saturated is the saturated vapor pressure, V is the volume of the washing chamber, and T is the absolute temperature, T = t_temperature + 273.15 (K), where t_temperature is the gas temperature detected by the temperature detection unit.
8. The humidity detection method according to claim 1, characterized in that, The process of obtaining the total energy provided by the heating device during the inlet and outlet cycle includes: Based on the heating power and heating duration of the heating device during the inlet and outlet cycle, the total energy provided by the heating device during the inlet and outlet cycle is obtained.
9. A method for controlling a dishwasher, characterized in that, include: The relative humidity in the washing chamber of the dishwasher is obtained using the humidity detection method as described in any one of claims 1 to 8; When the drying process is executed, the heating parameters are controlled based on the relative humidity, and the heating parameters include heating power and / or heating duration.
10. The control method according to claim 9, characterized in that, The heating parameters controlled based on the relative humidity include: The degree of dryness in the washing chamber is predicted based on the relative humidity, the gas temperature in the washing chamber, and the heating time. Heating parameters are controlled based on the degree of dryness.