A dishwasher and a control method thereof

Abstract

The embodiment of the application discloses a kind of dish washer and its control method, the dish washer includes: water tank, water pump and cleaning cavity, the water inlet and water outlet of water tank are provided with filter screen;Water tank top is provided with Reed tube float;The method can include: according to the state variation of Reed tube float and the working voltage variation of water pump, the pump water flow rate of water pump is corrected in advance;According to the pump water flow rate of pre-correction and the pump water quantity required for washing at this time, the pump water duration required for water pump in pump water process is calculated;After dish washer enters water inlet washing procedure, start water pump, pump water in cleaning cavity in water tank, and according to pump water duration control water pump stop time. Through the embodiment scheme, flow control is realized without water flow sensor, and the accuracy of control is guaranteed.

Description

Technical Field

[0001] This article relates to kitchen appliance control technology, particularly a dishwasher and its control method. Background Technology

[0002] Currently, most dishwashers use flow meters to control the water intake. Flow meters include Hall effect and reed switch types. Hall effect flow meters are more expensive, while reed switch flow meters have larger detection errors, are easily broken, and can lead to detection failures. Using other water flow sensors generally increases product costs, making the product less competitive. Furthermore, the use of AC water pumps and solenoid valves in the water inlet pipes presents challenges. AC water pumps have low precision in controlling the water intake, and foreign objects such as hair can easily cause blockages. The water flow rate is also susceptible to voltage fluctuations. Summary of the Invention

[0003] This application provides a dishwasher and its control method, which can achieve flow statistics without a water flow sensor and ensure the accuracy of control.

[0004] This application provides a control method for a dishwasher, which may include: a water tank, a water pump, and a washing chamber; both the inlet and outlet of the water tank are equipped with filters; a reed switch float is provided on the top of the water tank; the method may include:

[0005] The pumping speed of the water pump is pre-corrected based on the state changes of the reed switch float and the changes in the operating voltage of the water pump;

[0006] The pumping time required by the water pump during the pumping process is calculated based on the pre-calibrated pumping flow rate and the amount of water required for the current cleaning cycle. After the dishwasher enters the water inlet washing process, the water pump is started to pump the water in the water tank into the cleaning chamber, and the stopping time of the water pump is controlled according to the pumping time.

[0007] In an exemplary embodiment of this application, the step of pre-correcting the pump flow rate of the water pump based on the state changes of the reed switch float and the operating voltage changes of the water pump, and obtaining the full-load voltage V1 and no-load voltage V2 of the water pump, may include:

[0008] The state of the water tank, the full-load voltage V1 of the water pump, the pumping start time, and the pumping duration start time are determined based on the state of the reed switch float; the state of the water tank includes a full state or a partially full state.

[0009] The timing end time of the pumping time and the no-load voltage V2 of the pump are determined based on the changes in the operating voltage of the pump.

[0010] The total pumping time T is calculated based on the start and end times of the timing, and the pumping velocity of the water pump is calculated according to the preset formula Q = V / T; where Q is the pumping velocity and V is the total capacity of the water tank.

[0011] In an exemplary embodiment of this application, determining the state of the water tank, the full-load voltage V1 of the water pump, the pumping start time, and the timing start time of the pumping duration based on the state of the reed switch float may include:

[0012] When the reed switch float is in the set position, the water pump is controlled to start pumping water from the water tank into the cleaning chamber, and the operating voltage of the water pump at this time is collected as the full load voltage V1; the set position is used to indicate that the water tank is full.

[0013] When the reed switch float changes from the set state to the reset state, it starts timing the pumping time; the reset state is used to indicate that the water tank is not full.

[0014] In an exemplary embodiment of this application, determining the timing end time of the pumping time and the no-load voltage V2 of the pump based on the changes in the operating voltage of the pump may include:

[0015] During the pumping process, the operating voltage of the pump is collected once at a preset sampling period, and the change of the operating voltage based on the full load voltage V1 is detected. When a sudden change in the operating voltage is detected, the operating voltage after the change is taken as the no-load voltage V2, and the timing is stopped.

[0016] In an exemplary embodiment of this application, the method may further include: calibrating the pumping flow rate of the water pump using the reed float during the pumping process.

[0017] In an exemplary embodiment of this application, calibrating the pump flow rate of the water pump via the reed switch float may include:

[0018] During the water pumping process, the first time T1 experienced when the reed float moves from a preset first position to a preset second position is detected;

[0019] Obtain the height between the first position and the second position, and calculate the first capacity V1 of the water tank between the first position and the second position based on the height and the bottom area of ​​the water tank;

[0020] Calculate the first pump water flow rate Q1 within the first time period based on the first duration T1 and the first capacity V1.

[0021] The pre-calibrated pump flow rate Q is calibrated using the first pump flow rate Q1.

[0022] In an exemplary embodiment of this application, the method may further include: during the pumping process, detecting whether the current pumping flow rate decreases; when the current pumping flow rate decreases, extending the preset pumping time during this pumping process to compensate for the decrease in pumping flow rate.

[0023] In an exemplary embodiment of this application, detecting whether the current pump water flow rate decreases may include:

[0024] The deviation between the total water intake time required for the previous dishwasher wash and the preset standard total water intake time is detected.

[0025] Based on the different time ranges in which the deviation occurs, it is determined whether the current pump water flow rate has decreased and the degree of decrease.

[0026] In an exemplary embodiment of this application, the method may further include:

[0027] If the reed switch float is still in the set position after the preset pumping time has started, it is determined that the water tank outlet is blocked, and an alarm is triggered.

[0028] This application embodiment also provides a dishwasher, which may include: a water tank, a water pump, a washing chamber, a main control unit, a memory unit, and a sampling circuit for the water pump operating voltage. The water tank is equipped with filters at both the inlet and outlet. A reed switch float is provided on the top of the water tank. The memory unit stores instructions, and when the instructions are executed by the main control unit, the control method of the dishwasher described in any of the above embodiments is implemented.

[0029] Compared with related technologies, the dishwasher described in this embodiment may include: a water tank, a water pump, and a cleaning chamber. Both the inlet and outlet of the water tank are equipped with filters. A reed switch float is installed on the top of the water tank. The method may include: pre-calibrating the pumping speed of the water pump based on the state changes of the reed switch float and the operating voltage changes of the water pump; calculating the required pumping time of the water pump during the pumping process based on the pre-calibrated pumping speed and the amount of water required for the current wash; after the dishwasher enters the water intake washing process, starting the water pump to pump water from the water tank into the cleaning chamber, and controlling the stopping time of the water pump according to the pumping time. This embodiment achieves flow rate statistics without a water flow sensor and ensures control accuracy.

[0030] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the solutions described in the description and the accompanying drawings. Attached Figure Description

[0031] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0032] Figure 1 This is a flowchart of a dishwasher control method according to an embodiment of this application;

[0033] Figure 2 This is a schematic diagram of the sampling circuit for the water pump operating voltage according to an embodiment of this application;

[0034] Figure 3 This is a schematic diagram of a water pump flow rate correction method according to an embodiment of this application;

[0035] Figure 4 This is a schematic diagram of the pump water flow velocity attenuation compensation scheme according to an embodiment of this application;

[0036] Figure 5 This is a schematic diagram of the dishwasher structure according to an embodiment of this application. Detailed Implementation

[0037] This application describes several embodiments, but these descriptions are exemplary and not restrictive, and it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with, or may replace, any feature or element of any other embodiment.

[0038] This application includes and contemplates combinations of features and elements known to those skilled in the art. The embodiments, features, and elements disclosed in this application may also be combined with any conventional features or elements to form a unique inventive scheme as defined by the claims. Any feature or element of any embodiment may also be combined with features or elements from other inventive schemes to form another unique inventive scheme as defined by the claims. Therefore, it should be understood that any feature shown and / or discussed in this application may be implemented individually or in any suitable combination. Therefore, the embodiments are not limited except by the limitations imposed by the appended claims and their equivalents. Furthermore, various modifications and changes may be made within the scope of the appended claims.

[0039] Furthermore, in describing representative embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to the specific order of steps described herein, to the extent that it does not depend on such a specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Moreover, the claims concerning the method and / or process should not be limited to the steps performed in the written order, and those skilled in the art will readily understand that these orders can be varied and still remain within the spirit and scope of the embodiments of this application.

[0040] This application provides a control method for a dishwasher, which may include: a water tank, a water pump, and a washing chamber; both the inlet and outlet of the water tank are equipped with filters; a reed switch float is provided on the top of the water tank; as... Figure 1 As shown, the method may include steps S101-S102:

[0041] S101. The pumping speed of the water pump is pre-corrected based on the state changes of the reed switch float and the working voltage changes of the water pump.

[0042] S102. Calculate the pumping time required by the water pump during the pumping process based on the pre-calibrated pumping flow rate and the amount of water required for the current cleaning; after the dishwasher enters the water inlet washing process, start the water pump to pump the water in the water tank into the cleaning chamber, and control the stopping time of the water pump according to the pumping time.

[0043] In an exemplary embodiment of this application, the water pump can be a DC pump. The dishwasher may further include: a power supply unit, a main control unit, a memory unit, a water pump drive unit, and a sampling circuit for the water pump operating voltage.

[0044] In an exemplary embodiment of this application, the power supply unit may include: an AC-DC (alternating current to direct current) conversion module, a DC-DC (direct current to direct current) step-down module, a filter capacitor, a switching diode, a battery, and a current-limiting resistor; the main control unit may include a microcontroller (MCU).

[0045] In exemplary embodiments of this application, as Figure 2 As shown, the water pump drive unit may include transistor A. The sampling circuit (or analog-to-digital converter detection circuit) for the water pump operating voltage may include sampling voltage divider resistors R515 and R514 and filter capacitor C301.

[0046] In an exemplary embodiment of this application, the transistor can drive the water pump to "turn on" and "turn off", and R514 and R515 are sampling resistors that collect different AD values ​​when the water pump is turned on and off.

[0047] In an exemplary embodiment of this application, CN3 is the interface of the water pump. When the water pump switches between full load and no load states, the circuit current of the water pump changes, so the voltage across CN3 changes, and the voltage division of R515 and R514 below changes. When the water tank is full and water is about to be discharged, the DRI is set to a high level, the transistor A is turned on, and the current of R515 and R514 will change. The ADC is a signal output port that can be connected to the main control unit.

[0048] In an exemplary embodiment of this application, the dishwasher water tank has a first filter screen at the top inlet, which mainly filters out large particles in tap water. The top of the water tank is also equipped with a reed float. The bottom of the water tank has an outlet, and a second filter screen is added to the outlet. The water tank outlet is directly connected to a water pump.

[0049] In an exemplary embodiment of this application, the filter screen designed on the top of the water tank mainly filters out large particles in tap water or prevents foreign objects from accidentally entering the water tank cavity due to human factors. The water pump channel is relatively small, and a second filter screen is added at the water tank outlet to prevent cotton-like foreign objects from clogging the water pump (experiments show that the inlet pump has strong anti-interference ability against clogging by foreign objects such as sand, but weak anti-interference ability against foreign objects such as cotton).

[0050] In an exemplary embodiment of this application, a reed switch float is disposed at the top of the water tank. Generally, the float mainly detects whether the water tank is full. If it is full, it is set; if it is not full, it is reset. (The reed switch float is disposed at the top of the water tank. When the water tank is empty or not full, the float is in the reset state. When water is added manually or automatically, when the water in the tank pushes the float up, the reed switch float is set. Detecting the float set signal determines that the water tank is full.)

[0051] In an exemplary embodiment of this application, the improved float of this application embodiment is a multi-segment detection structure, which not only detects whether the water tank is full or empty, but also calibrates the water inlet pump.

[0052] In an exemplary embodiment of this application, the method further includes: monitoring the operating voltage of the water pump during the pumping process based on the full-load voltage V1 and no-load voltage V2 of the water pump obtained during the water flow rate correction process; when the current operating voltage of the water pump is detected by a preset sampling circuit as the full-load voltage V1, determining that the water tank is full and the water pump has just started pumping water; when the current operating voltage of the water pump is detected by the sampling circuit as the no-load voltage V2, determining that the water tank is empty and the water pump needs to be stopped.

[0053] In an exemplary embodiment of this application, both the full-load voltage V1 and the no-load voltage V2 can be obtained during the correction process of the pump water flow rate before leaving the factory.

[0054] In an exemplary embodiment of this application, the step of pre-correcting the pump flow rate of the water pump based on the state changes of the reed switch float and the operating voltage changes of the water pump, and obtaining the full-load voltage V1 and no-load voltage V2 of the water pump, may include:

[0055] The state of the water tank, the full-load voltage V1 of the water pump, the pumping start time, and the pumping duration start time are determined based on the state of the reed switch float; the state of the water tank includes a full state or a partially full state.

[0056] The timing end time of the pumping time and the no-load voltage V2 of the pump are determined based on the changes in the operating voltage of the pump.

[0057] The total pumping time T is calculated based on the start and end times of the timing, and the pumping velocity of the water pump is calculated according to the preset formula Q = V / T; where Q is the pumping velocity and V is the total capacity of the water tank.

[0058] In an exemplary embodiment of this application, the dishwasher can perform a factory self-test, that is, the pump's inlet water flow rate can be calibrated using the pump's own operating characteristics before leaving the factory. The pump water flow rate calibration scheme for the dishwasher is described in detail below.

[0059] In an exemplary embodiment of this application, determining the state of the water tank, the full-load voltage V1 of the water pump, the pumping start time, and the timing start time of the pumping duration based on the state of the reed switch float may include:

[0060] When the reed switch float is in the set position, the water pump is controlled to start pumping water from the water tank into the cleaning chamber, and the operating voltage of the water pump at this time is collected as the full load voltage V1; the set position is used to indicate that the water tank is full.

[0061] When the reed switch float changes from the set state to the reset state, it starts timing the pumping time; the reset state is used to indicate that the water tank is not full.

[0062] In an exemplary embodiment of this application, determining the timing end time of the pumping time and the no-load voltage V2 of the pump based on the changes in the operating voltage of the pump may include:

[0063] During the pumping process, the operating voltage of the pump is collected once at a preset sampling period, and the change of the operating voltage based on the full load voltage V1 is detected. When a sudden change in the operating voltage is detected, the operating voltage after the change is taken as the no-load voltage V2, and the timing is stopped.

[0064] In an exemplary embodiment of this application, when the float is in the set position, the water tank is full of water, and the water volume is V. The water pump is turned on and starts pumping water. At this time, the water pump is fully loaded, and the voltage V1 formed on the sampling resistor when the pump is fully loaded (i.e., the full-load voltage of the water pump) can be recorded. During the process of water discharge from the water tank, the water level in the water tank gradually decreases. When the float changes from the set position to the reset position, the timing starts. When the water pump is working, the voltage V2 formed on the sampling resistor changes abruptly relative to V1 (if the water pump voltage changes abruptly multiple times, it is assumed that the water pump voltage changes abruptly). At this time, it is assumed that the pump is in an unloaded state, and there is no water in the water tank. The voltage V2 in the unloaded state is recorded, the timing stops, and the total pumping time T is calculated.

[0065] In the exemplary embodiment of this application, the dishwasher undergoes a boiling water test before leaving the factory. Given a known water tank volume of V, the water pump's inlet flow rate Q needs to be determined in advance during operation. An alarm is triggered if the water pump's flow rate deviates too much or too little from the standard value, thus improving the overall reliability of the machine and providing a better customer experience.

[0066] In an exemplary embodiment of this application, based on the working characteristics of a DC pump, the current magnitudes under load (water pumping) and no-load (air pumping) operating states are significantly different. Therefore, the voltage magnitudes formed across the sampling resistor differ considerably. The dishwasher main control unit can pre-collect the voltage V1 when the water pump is fully loaded and the voltage V2 when it is unloaded, as a basis for judging the working state of the water pump during subsequent water pumping processes. It can also promptly control the water pump to stop working when the detected voltage value is the no-load voltage V2.

[0067] In an exemplary embodiment of this application, timing T begins after the float changes from the set state to the reset state (i.e., the water tank discharge time increases by one second). At this time, the full-load voltage V1 is collected. When the working voltage of the water pump is collected for 5 seconds and V2 is obtained, the timing is stopped to obtain the total pumping time T = 5 seconds. At this time, the pumping speed Q of the water pump is: Q = V / T; Q is the pumping speed of the water pump, V is the total capacity of the dishwasher water tank, and T is the total pumping time of the water tank from full to empty.

[0068] In exemplary embodiments of this application, as Figure 3 As shown, a detailed embodiment of the dishwasher's factory self-test, which uses the water pump's own operating characteristics to correct the water pump's inlet flow rate, is given.

[0069] In an exemplary embodiment of this application, after entering the self-test function, it can detect whether water has started to enter the water tank. When no water is detected, the water pump has not yet started. The sampling circuit detects the voltage V0 of the water pump at this time and detects whether V0 > 200 (200 is a digital quantity). If V0 > 200, it can be determined that the circuit is abnormal and an alarm is triggered to prompt the staff to repair it. When water is detected entering the water tank or when V0 ≤ 200, the reed switch float is checked for position (if it is, the water tank is full). If the reed switch float is not in position, the check continues. When the reed switch float is in position, the water pump is turned on and begins pumping water from the water tank into the dishwasher's cleaning chamber. After pumping begins, the reed switch float is checked for reset (if it is, the water in the tank is decreasing). If the reed switch float is not in reset position, the check continues. When the reed switch float is in reset position, a timer is started, and the pump's operating voltage is repeatedly sampled using a sampling resistor, and the average value is recorded as V1 (at this time, the pump is in pumping mode, and V1 is considered to be the full-load voltage formed on the sampling resistor when the pump is fully loaded). During the pumping process, the voltage formed on the sampling resistor can be sampled every 4ms, and 250 voltages can be sampled in 1 second to obtain the average value of the pump's operating voltage V3. The system determines whether the calculated pump voltage V3 changes abruptly relative to the full-load voltage V1, i.e., Delta = V1 - V3, and checks if Delta > 100 (if it exceeds 100, the voltage value sampled across the sampling resistor is considered to have changed abruptly). If the calculated pump voltage V3 does not change abruptly relative to the full-load voltage V1, the system continues to sample the pump voltage across the sampling resistor every 4ms. If the calculated pump voltage V3 changes abruptly relative to the full-load voltage V1, the system continues to sample the pump voltage across the sampling resistor every 4ms, averaging 250 voltages per second to obtain the pump operating voltage V3, which is then used to verify the detection results again. The system then determines whether the operating voltage V3 sampled for 3 consecutive seconds satisfies Delta > 100. If so, the current operating voltage V3 is confirmed to be the no-load voltage V2, the timer stops, and the total pumping time is obtained. At this point, the values ​​of V1 and V2 can be written to memory. If not, the system continues to sample the pump voltage across the sampling resistor every 4ms.

[0070] In an exemplary embodiment of this application, the method may further include: calibrating the pumping flow rate of the water pump using the reed float during the pumping process.

[0071] In an exemplary embodiment of this application, calibrating the pump flow rate of the water pump via the reed switch float may include:

[0072] During the water pumping process, the first time T1 experienced when the reed float moves from a preset first position to a preset second position is detected;

[0073] Obtain the height between the first position and the second position, and calculate the first capacity V1 of the water tank between the first position and the second position based on the height and the bottom area of ​​the water tank;

[0074] Calculate the first pump water flow rate Q1 within the first time period based on the first duration T1 and the first capacity V1.

[0075] The pre-calibrated pump flow rate Q is calibrated using the first pump flow rate Q1.

[0076] In the exemplary embodiments of this application, the current method for detecting whether the dishwasher water tank is full is based on whether a float reed switch is in the correct position. However, this single signal is inconvenient for measuring the amount of water entering the dishwasher's inner tub (washing chamber) per unit time (i.e., the pump flow rate). This embodiment of the application designs a segmented reed switch within the water tank to detect the amount of water entering the inner tub per unit time, thereby calculating the pump flow rate.

[0077] In an exemplary embodiment of this application, the position of the reed switch float in the set state can be recorded as the first position. That is, when the water tank is full, the reed switch float reaches the first position and is in the set state, sending a signal that the water tank is full. After the dishwasher enters the water inlet washing process, the water pump is turned on to pump water from the water tank to the washing chamber. After pumping water for a period of time, the reed switch float leaves the first position and is in the reset state. At this time, the pumping time is started. When the reed switch float reaches the second position, the timing stops, and the pumping time from the start of pumping to this moment (i.e., the first time T1) is obtained. The actual pumping flow rate Q1 of the water pump is calculated based on the drainage capacity of the water between the first position and the second position (first capacity V1), the first time T1, and the formula Q1 = V1 / T1.

[0078] In the exemplary embodiment of this application, the purpose of this functional design is that the operating current of the factory-installed water pump differs between full load (pumping water) and no load (pumping air). If the pump parameters are not calibrated, excessive differences in the pump current will lead to false alarms during subsequent machine operation. For example, if the no-load operating current of water pump 1 is similar to that of water pump 2, the program will misjudge. Pre-calibration can increase the reliability of water intake judgment. Theoretically, no operating voltage should be collected when the water pump is not working. However, if a voltage much greater than 0 is collected, an alarm will be triggered. This enables self-testing of the main control unit's drive and detection, and also increases the reliability of the main control unit.

[0079] In exemplary embodiments of this application, as Figure 4 As shown, the method may further include: during the pumping process, detecting whether the current pumping flow rate decreases; when the current pumping flow rate decreases, extending the preset pumping time during this pumping process to compensate for the decrease in pumping flow rate.

[0080] In an exemplary embodiment of this application, detecting whether the current pump water flow rate decreases may include:

[0081] The deviation between the total water intake time required for the previous dishwasher wash and the preset standard total water intake time is detected.

[0082] Based on the different time ranges in which the deviation occurs, it is determined whether the current pump water flow rate has decreased and the degree of decrease.

[0083] In an exemplary embodiment of this application, after prolonged use, small particles in tap water gradually aggregate, forming large flocculent objects. This significantly affects the water pump's inlet flow rate. Consequently, the water intake, which was originally scheduled to occur over time, becomes less at any given time. Without compensation, insufficient water intake for each function results in inadequate cleaning of dishes and wasted water from the tank. To address these issues, a compensation algorithm is employed to compensate for the pumping time. The scheme for compensating for pumping time is described in detail below.

[0084] In an exemplary embodiment of this application, when the inlet pump is slightly clogged, calibration data can be obtained by calibrating the pump's flow rate error according to factory requirements. The normal standard flow rate of the pump is Q, and the inlet water capacity V requires a duration T (data Q, V, and T are obtained from factory calibration). After the machine has been used for a certain period of time, the DC diaphragm pump experiences a flow rate decrease, and the inlet water capacity V requires Ts, where Ts > T (Note: the standard inlet water V liters require T, but the inlet flow rate decreases due to pump lifespan or slight blockage by foreign objects). Because the control method is to control the inlet water according to the duration, when the inlet pump's inlet water flow rate decreases, the inlet water duration must be extended to ensure that the inlet water volume meets the washing requirements. If the inlet water volume is not compensated, the circulating pump will not be able to clean properly, resulting in incomplete washing; and there will be a large amount of water remaining in the water tank, leading to resource waste.

[0085] In an exemplary embodiment of this application, the calculation method for extending the water pumping time can be as follows: For example, the total capacity of the water tank is 5L, and the water intake for the first wash is set to 1700ml, the second wash to 1700ml, and the third wash to 1700ml (the remaining water volume is reserved as a margin). The initial water intake of 1700ml takes 100s. Now, due to the decrease in flow rate, the water intake time is increased by 25s, for a total water intake time of 125s. At the same time, the water intake can be compensated according to the water pump's attenuation program, with different compensation times for slight, moderate, and severe water intake. For example, a slight compensation of 10s, a moderate compensation of 20s, and a severe compensation of 30s. With a slight compensation of 20s, the original setting for the first wash is 100s, and the water intake time after compensation is 120s.

[0086] In the exemplary embodiment of this application, to prevent excessive compensation—specifically, excessive water intake leading to leakage, or insufficient water in the three-wash spray arm failing to rotate—actually, based on experimental data, the maximum water intake for the inner tank is currently 2L. When the water volume in the inner tank is less than 2L, leakage will not occur during washing. A normal washing function requires a water intake of 1.5L to meet washing requirements. Based on the self-test function, Q is calculated. The water intake time for 2L is T2 = (2L*1000) / Q, where T2 is in seconds. A normal water intake setting of 1.5L requires t seconds, with a maximum compensation time of 25 seconds. This satisfies T2>=t+25, ensuring that the maximum water intake does not cause the tank to overflow.

[0087] In an exemplary embodiment of this application, the method may further include:

[0088] If the reed switch float is still in the set position after the preset pumping time has started, it is determined that the water tank outlet is blocked, and an alarm is triggered.

[0089] In an exemplary embodiment of this application, after prolonged use of the dishwasher, small lint-like objects may become clogged on the filter. To prevent insufficient water intake into the inner tank, an alarm function is designed.

[0090] In an exemplary embodiment of this application, as mentioned above, a float is installed on the top of the water tank to detect whether the water tank is full of water. After the machine enters the water intake process, after a period of time, such as 20 seconds, it is determined again whether the float still has a signal. If there is a signal, it can be determined that the water intake pump is blocked, and the alarm prompt function is activated to remind the user to clean the filter.

[0091] In the exemplary embodiments of this application, the aforementioned scheme uses a reed switch float to calibrate the pump water flow rate, specifically utilizing the time difference between the upper and lower signals (because the volume between the upper and lower parts of the float is constant, the inlet flow rate Q = V / T, and the inlet flow rate decreases over time). In other embodiments, calibration can also be performed using an external device, such as a touch module, to detect changes in water level. A flow meter can also be connected for calibration, but this increases operational complexity and reduces work efficiency.

[0092] In exemplary embodiments of this application, the solutions of this application embodiments include at least the following advantages:

[0093] 1. Improved water intake process and clever utilization of the float structure: The float not only checks whether the water tank is full, but also, through structural improvements, enables the calibration, compensation, and blockage detection of the pump's flow rate, achieving closed-loop control of the DC water pump's intake. It also identifies abnormalities in the intake, determines how to handle blockages in the DC pump's intake, and addresses control circuit failures. Furthermore, it calibrates for inconsistencies in intake flow caused by errors in different pumps, improving reliability and providing intake compensation.

[0094] 2. Utilizing the inherent characteristics of DC pumps: By utilizing the principle that the operating current of a DC pump differs significantly between full load and no load, the inlet flow rate of the water pump can be calibrated.

[0095] 3. Provide timely compensation and alarm notification after the pump water flow rate decreases.

[0096] 4. It can detect whether the water pump control is malfunctioning and change the washing process to protect itself if it fails.

[0097] This application also provides a dishwasher 1, such as... Figure 5 As shown, it may include: a water tank 11, a water pump 12, a cleaning chamber 13, a main control unit 14, a memory unit 15, and a sampling circuit 16 for the water pump operating voltage. The water tank 11 is equipped with filters at both the inlet and outlet. A reed switch float 17 is provided on the top of the water tank 11. The memory unit 15 stores instructions, and when the instructions are executed by the main control unit 14, the control method of the dishwasher described above is implemented.

[0098] In the exemplary embodiments of this application, any of the embodiments in the above method embodiments are applicable to the dishwasher embodiment, and will not be described in detail here.

[0099] It will be understood by those skilled in the art that all or some of the steps, systems, or apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software may be distributed on a computer-readable medium, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

Claims

1. A method for controlling a dishwasher, characterized in that, The dishwasher includes: a water tank, a water pump, and a cleaning chamber; both the inlet and outlet of the water tank are equipped with filters; a reed switch float is installed on the top of the water tank; the method includes: The pumping speed of the water pump is pre-corrected based on the state changes of the reed switch float and the changes in the operating voltage of the water pump; The pumping time required by the water pump during the pumping process is calculated based on the pre-calibrated pumping flow rate and the amount of water required for the current cleaning cycle. After the dishwasher enters the water inlet washing process, the water pump is started to pump the water in the water tank into the cleaning chamber, and the stopping time of the water pump is controlled according to the pumping time. Obtain the full-load voltage V1 and no-load voltage V2 of the water pump; The state of the water tank, the full-load voltage V1 of the water pump, the pumping start time, and the pumping duration start time are determined based on the state of the reed switch float; the state of the water tank includes a full state or a partially full state. The timing end time of the pumping time and the no-load voltage V2 of the pump are determined based on the changes in the operating voltage of the pump. The total pumping time T is calculated based on the start and end times of the timing, and the pumping velocity of the water pump is calculated according to the preset formula Q = V / T; where Q is the pumping velocity and V is the total capacity of the water tank.

2. The control method for a dishwasher according to claim 1, characterized in that, The determination of the state of the water tank, the full-load voltage V1 of the water pump, the pumping start time, and the timing start time of the pumping duration based on the state of the reed switch float includes: When the reed switch float is in the set position, the water pump is controlled to start pumping water from the water tank into the cleaning chamber, and the operating voltage of the water pump at this time is collected as the full load voltage V1; the set position is used to indicate that the water tank is full. When the reed switch float changes from the set state to the reset state, it starts timing the pumping time; the reset state is used to indicate that the water tank is not full.

3. The control method for a dishwasher according to claim 1 or 2, characterized in that, The step of determining the timing end time of the pumping time and the no-load voltage V2 of the pump based on the changes in the operating voltage of the pump includes: During the pumping process, the operating voltage of the pump is collected once at a preset sampling period, and the change of the operating voltage based on the full load voltage V1 is detected. When a sudden change in the operating voltage is detected, the operating voltage after the change is taken as the no-load voltage V2, and the timing is stopped.

4. The control method for a dishwasher according to claim 1, characterized in that, The method further includes calibrating the pumping flow rate of the water pump using the reed float during the pumping process.

5. The dishwasher control method according to claim 4, characterized in that, The calibration of the pump flow rate of the water pump via the reed switch float includes: During the water pumping process, the first time T1 experienced when the reed float moves from a preset first position to a preset second position is detected; Obtain the height between the first position and the second position, and calculate the first capacity V1 of the water tank between the first position and the second position based on the height and the bottom area of ​​the water tank; Calculate the first pump water flow rate Q1 within the first time period based on the first duration T1 and the first capacity V1. The pre-calibrated pump flow rate Q is calibrated using the first pump flow rate Q1.

6. The control method for a dishwasher according to claim 1, characterized in that, The method further includes: during the pumping process, detecting whether the current pumping flow rate decreases; when the current pumping flow rate decreases, extending the preset pumping time during this pumping process to compensate for the decrease in pumping flow rate.

7. The dishwasher control method according to claim 6, characterized in that, The detection of whether the current pump water flow rate has decreased includes: The deviation between the total water intake time required for the previous dishwasher wash and the preset standard total water intake time is detected. Based on the different time ranges in which the deviation occurs, it is determined whether the current pump water flow rate has decreased and the degree of decrease.

8. The control method for a dishwasher according to claim 1, characterized in that, The method further includes: If the reed switch float is still in the set position after the preset pumping time has started, it is determined that the water tank outlet is blocked, and an alarm is triggered.

9. A dishwasher, characterized in that, include: The system includes a water tank, a water pump, a cleaning chamber, a main control unit, a memory unit, and a sampling circuit for the water pump's operating voltage. Both the inlet and outlet of the water tank are equipped with filters. A reed switch float is installed on the top of the water tank. The memory unit stores instructions, and when the instructions are executed by the main control unit, the dishwasher control method described in any one of claims 1-8 is implemented.

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