A cleaning machine and a control method thereof

Abstract

The present invention relates to a cleaning machine, comprising a water cup, a volute arranged at the bottom of the water cup, an impeller arranged in the volute, a motor arranged below the water cup and connected to the impeller, a heater arranged in the water cup and below the volute, a controller connected to the motor and the heater by electrical signals, a first temperature detector and a second temperature detector connected to the controller by electrical signals are arranged in the water cup, the first temperature detector is arranged at a height between the water suction port at the bottom of the volute and the upper surface of the heater, and the second temperature detector is arranged at a height above the water suction port of the volute. The cleaning machine can effectively avoid dry burning of the heating tube without additionally setting a water level sensor. The present invention also relates to a control method of the cleaning machine, which can accurately determine whether there is a risk of dry burning in a foaming state.

Description

Technical Field

[0001] The invention relates to a cleaning machine and also to a control method of the cleaning machine. Background Art

[0002] The cleaning machine will be equipped with a heater at the bottom of the water cup to heat the incoming water, which is beneficial to improve the cleaning effect. During normal use of the cleaning machine, the dynamic water level in the cleaning machine is usually higher than the setting height of the heater, thereby ensuring that the heater is as far as possible from being dry-burned or semi-dry-burned as possible during the use of the cleaning machine, and ensuring that the heater works reliably for a long time. In this case, it is necessary to be able to timely and accurately judge the dry-burning of the heater, and then turn off the heater to avoid dry-burning or semi-dry-burning of the heating tube.

[0003] In the prior art, a water level sensor is usually set in the washing machine to detect the water level, and then determine whether the water level is above the heater. For example, the Chinese utility model patent "A dishwasher heating box" with authorization announcement number CN215305653U (application number 202121663249.2), and the Chinese utility model patent "A new dishwasher" with authorization announcement number CN210169993U (application number 201920735843.4), both of which disclose dishwashers with water temperature sensors, which are used to detect whether the water level in the dishwasher is higher than the heater, and then judge based on the water level to prevent dry burning. However, in these dishwashers, water level sensors and corresponding setting structures need to be set, which are costly and more complicated to process. Summary of the invention

[0004] The first technical problem to be solved by the present invention is to provide a cleaning machine that can effectively avoid the dry burning of the heating tube without the need for an additional water level sensor in view of the above-mentioned prior art.

[0005] The second technical problem to be solved by the present invention is to provide a control method for a cleaning machine capable of accurately judging whether there is a risk of dry burning in a bubbling state, with respect to the above-mentioned prior art.

[0006] The third technical problem to be solved by the present invention is to provide a control method for a cleaning machine that can determine whether the water intake into the cleaning machine meets the demand in view of the above-mentioned prior art.

[0007] The technical solution adopted by the present invention to solve the above-mentioned first technical problem is: a cleaning machine, including a water cup, a volute arranged in the bottom of the water cup, an impeller arranged in the volute, a motor arranged below the water cup and connected to the impeller, a heater arranged in the water cup and below the volute, and a controller electrically connected to the motor and the heater respectively, characterized in that a first temperature detector and a second temperature detector electrically connected to the controller respectively are provided in the water cup, the first temperature detector is set at a height between the water suction port at the bottom of the volute and the upper surface of the heater, and the second temperature detector is set at a height above the water suction port of the volute.

[0008] The structure is simple and easy to install. The first temperature detector and the second temperature detector are fixedly arranged on the side wall of the water cup.

[0009] A control method for a cleaning machine as described above is characterized in that: when the cleaning machine is working, the controller obtains the motor power and determines the relationship between the water level in the water cup and the heights of the first temperature detector and the second temperature detector based on the motor power, and then determines whether to turn on the heating tube based on the relationship between the water level in the water cup and the heights of the first temperature detector and the second temperature detector.

[0010] The technical solution adopted by the present invention to solve the above second technical problem is: in order to avoid the misjudgment of dry burning caused by the motor power, if the fluctuation of the motor power exceeds the set fluctuation range, it is judged that there is a problem of bubbling in the water cup;

[0011] At this time, if the heater is in the on state, the controller obtains the detection temperature of the second temperature detector. If the detection temperature of the second temperature detector exceeds the set high temperature threshold, it is determined that the foaming in the water cup is serious, and the controller controls to turn off the heater, otherwise the heater is kept on;

[0012] At this time, if the heater is in the off state, the controller controls to actively turn on the heater and work for the first set time according to the set heating power; in this process, the controller obtains the detection temperature of the second temperature detector. If the detection temperature rise of the second temperature detector exceeds the set temperature rise value within the first set time, it is judged that there is serious bubbling in the water cup, and the controller controls water to be fed into the cleaning machine; if the detection temperature rise of the second temperature detector does not exceed the set temperature rise value within the first set time, it is judged that the dynamic liquid level in the water cup is between the first temperature detector and the second temperature detector, and the controller controls the cleaning machine to turn on the heater normally according to the work flow.

[0013] Preferably, when the detected temperature rise of the second temperature detector exceeds the set temperature rise value within the first set time, the controller controls the water flow into the cleaning machine to be the water volume in the water cup corresponding to the height difference between the first temperature detector and the second temperature detector.

[0014] As an improvement, if the motor power continues to decrease within a set time period, the controller determines that the dynamic liquid level in the water cup is below the first temperature detector, and the controller controls the heater to stop working.

[0015] As an improvement, if the fluctuation amount of the motor power is within the set fluctuation range, it is determined that the dynamic liquid level in the water cup is above the second temperature detector, and the controller controls the heater to perform heating.

[0016] The technical solution adopted by the present invention to solve the third technical problem is: a control method of the washing machine as described above, characterized in that: before water enters the water cup, the controller obtains the initial detection temperature T10 of the first temperature detector and the initial detection temperature T20 of the second temperature detector;

[0017] The controller fills water into the water cup according to the set water filling time. After the water filling is completed, the controller obtains the real-time detection temperature T11 of the first temperature detector and the real-time detection temperature T21 of the second temperature detector;

[0018] The controller calculates the temperature change value ΔT1 of the first temperature detector and the temperature change value ΔT2 of the second temperature detector, and determines whether the water level in the water cup exceeds that of the second temperature detector according to ΔT1 and ΔT2.

[0019] As an improvement, if ΔT1 and ΔT2 are both greater than the set first temperature difference value, and the temperature difference between T11 and T21 is less than the set second temperature difference value, it is judged that the water level in the water cup is above the second temperature detector; otherwise, the controller controls to actively start the heater to work for the second set time, and the controller obtains the detection temperature of the first temperature detector within the second set time range in real time, and calculates the temperature rise value ΔT11 of the first temperature detector within the second set time range; the controller obtains the detection temperature of the second temperature detector within the second set time range in real time, and calculates the temperature rise value ΔT21 of the second temperature detector within the second set time range; if ΔT11 and / or ΔT21 exceed the set temperature rise threshold, it is judged that the water inlet level of the cleaning machine does not exceed the second temperature detector; if ΔT11 and ΔT21 are both less than the set minimum temperature rise value, it is judged that the water inlet level of the cleaning machine exceeds the second temperature detector.

[0020] Compared with the prior art, the advantages of the present invention are that: the cleaning machine in the present invention is provided with temperature detectors at different heights, and based on the heights of the first temperature detector and the second temperature detector relative to the volute water suction port and the heater, the water level of the water cup can be judged based on the temperature changes of the two. In this way, the water level in the water cup can be understood without setting up a special water level detector, which is low-cost and simplifies the structure inside the water cup.

[0021] The control method of the cleaning machine in the present invention, without setting a water level detector, combines the motor power and the temperature changes of the first temperature detector and the second temperature detector to effectively determine the water level in the water cup and avoid the problem of dry burning of the heater.

[0022] The control method of the cleaning machine in the present invention, without setting a water level detector, can also judge whether the water intake in the water cup satisfies the problem of the heater drying out during operation according to the temperature changes of the first temperature detector and the second temperature detector, thereby ensuring the safety of the cleaning machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a three-dimensional diagram of a cleaning machine in an embodiment of the present invention.

[0024] Figure 2 It is a cross-sectional view of a cleaning machine in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below with reference to the accompanying drawings.

[0026] like Figure 1 and Figure 2 As shown, the cleaning machine in this embodiment includes a water cup 1, a volute 2 arranged at the bottom of the water cup 1, an impeller 21 arranged in the volute 2, a motor 3 arranged below the water cup 1 and connected to the impeller 21, a heater 4 arranged in the water cup 1 and located below the volute 2, and a controller connected to the motor 3 and the heater 4 respectively by electrical signals. The volute 2 is usually also provided with a spray arm that is rotationally constrained to spray water into the cleaning chamber of the water cup 1. A water suction port 22 is provided at the bottom of the volute 2. When the cleaning machine is used, the controller controls the motor 3 to rotate, and the motor 3 drives the impeller 21 to rotate, thereby sucking the water in the water cup 1 from the water suction port 22 at the bottom of the volute 2 into the volute 2, and based on the centrifugal action of the impeller 21, the water enters the spray arm and drives the spray arm to rotate and spray water. During the working process, the controller can obtain the working parameters of the motor 3 in real time, including the power of the motor 3, etc. In order to ensure the cleanliness, a heating and cleaning process will be set, so it is necessary to control the heater 4 to heat the water in the water cup 1.

[0027] The water cup 1 is provided with a first temperature detector 5 and a second temperature detector 6 which are respectively connected to the controller electrical signal. The first temperature detector 5 is set at a height between the water suction port 22 at the bottom of the volute 2 and the upper surface of the heater 4, and the second temperature detector 6 is set at a height above the water suction port 22 of the volute 2. In this embodiment, the first temperature detector 5 and the second temperature detector 6 are fixedly arranged on the side wall of the water cup 1, so that the structure is simple and convenient to install. In the prior art, the cleaning temperature is defined in the cleaning process, so at least one temperature detector for detecting the temperature is usually arranged in the water cup 1, while in this embodiment, only one temperature detector is added, and the temperature detector in this embodiment adopts an NTC device, which is also low in cost. Through the following control method, dry burning of the heater 4 can be effectively prevented without additionally setting a water level sensor.

[0028] When the cleaning machine is cleaning normally, the dynamic liquid level in the water cup 1 is usually above the second temperature detector 6, which can effectively prevent the heater 4 from drying out. The dynamic liquid level is the liquid level at the bottom of the water cup 1 after deducting the backflow water on the side wall of the water cup 1 and the spray water in the air.

[0029] In this embodiment, the control method of the aforementioned washing machine is as follows: When the washing machine is working, the controller obtains the power of the motor 3, and determines the relationship between the water level in the water cup 1 and the heights of the first temperature detector 5 and the second temperature detector 6 according to the power of the motor 3, and then determines whether to turn on the heating tube according to the relationship between the water level in the water cup 1 and the heights of the first temperature detector 5 and the second temperature detector 6, thereby avoiding the problem of dry burning of the heating tube.

[0030] When the cleaning machine is working, if the dynamic liquid level in the water cup 1 is below the first temperature detector 5, that is, the dynamic water level is lower than the water suction port 22 of the volute 2, it will cause serious air suction, and the power of the motor 3 will continue to decrease. If the dynamic liquid level of the water cup 1 is above the second temperature detector 6, that is, above the water suction port 22 of the volute 2, based on the operation of the motor 3, the volute 2 can stably suck water, and the power of the corresponding motor 3 is also in a stable state.

[0031] Based on this, in this embodiment, the controller first judges the acquired power of the motor 3. If the power of the motor 3 continues to decrease within the set time, the controller judges that the dynamic liquid level in the water cup 1 is below the first temperature detector 5. At this time, it is very easy for the heater 4 to dry burn. The controller controls the heater 4 to stop working, that is, if the heating tube has not been turned on at this time, the control will not turn on the heating tube. If the heating tube is in the on state at this time, the control will turn off the heating tube. If the fluctuation amount of the power of the motor 3 is within the set fluctuation range, that is, the power of the motor 3 is stable when the cleaning machine is working, the controller judges that the dynamic liquid level in the water cup 1 is above the second temperature detector 6, indicating that there is enough dynamic water in the water cup 1 to submerge the heater 4, and the heater 4 will not dry burn. At this time, the controller controls the heater 4 to perform heating work, that is, if the heater 4 has not started working, it can be directly turned on when it needs to start the heater 4. If the heater 4 has started working, the heating working state of the heater 4 is maintained.

[0032] In addition, during the cleaning process, there may be protein in the contaminants, the user may mistakenly add detergent, the rinse agent may leak, etc., all of which may cause foaming, and the foaming may reduce the medium density, which in turn causes the power of the motor 3 to fluctuate greatly and become unstable. However, in this case, the water level will drop to a certain extent due to the foam, and the water level may drop to between the first temperature detector 5 and the second temperature detector 6, or even drop below the first temperature detector 5. When it drops to between the first temperature detector 5 and the second temperature detector 6, it means that the bubbles are not serious and the heater 4 is not prone to dry burning. When it drops below the first temperature detector 5, it means that the bubbles are serious and the possibility of dry burning of the heater 4 is high, and it is necessary to stop the heater 4 from heating. In this embodiment, in view of this situation, in order to avoid the misjudgment of dry burning caused by foaming, the corresponding method is as follows.

[0033] If the fluctuation of the power of the motor 3 exceeds the set fluctuation range, it is determined that there is a foaming problem in the water cup 1. At this time, it is impossible to accurately determine whether the heater 4 will dry-burn based solely on the power of the motor 3.

[0034] At this time, if the heater 4 is in the on state, the controller obtains the detection temperature of the second temperature detector 6. If the detection temperature of the second temperature detector 6 exceeds the set high temperature threshold, it is judged that the foaming in the water cup 1 is serious, and the controller controls to turn off the heater 4, otherwise the heater 4 is kept on.

[0035] At this time, if the heater 4 is in the off state, before starting the heater 4, the controller controls to actively turn on the heater 4 and work for the first set time according to the set heating power. In this process, the controller obtains the detection temperature of the second temperature detector 6. If the detection temperature rise of the second temperature detector 6 exceeds the set temperature rise value within the first set time, it is judged that the bubbling in the water cup 1 is serious, and the controller controls water to be fed into the cleaning machine. In this embodiment, the controller controls the water intake amount of the water into the cleaning machine to be greater than or equal to the water amount required for the height difference between the first temperature detector 5 and the second temperature detector 6 in the water cup 1. The water intake amount is sufficient to eliminate the serious influence of bubbling on the dynamic water volume and avoid dry burning of the heater 4. If the detection temperature rise of the second temperature detector 6 within the first set time does not exceed the set temperature rise value, it is judged that the bubble situation of the dynamic water in the water cup 1 is not serious, and the dynamic liquid level in the water cup 1 is between the first temperature detector 5 and the second temperature detector 6. The dynamic water volume will not cause the dry burning of the heater 4, and the controller controls the cleaning machine to start the heater 4 normally according to the work flow.

[0036] In addition, since the water cup 1 is not provided with a water level sensor, the water inlet time of the cleaning machine is usually fixed, but it is inevitable that the water flow rate is small, so the water level in the water cup 1 may be insufficient, resulting in the heater 4 being dry-burned. In view of this situation, the following control method of the cleaning machine is used in this embodiment to control the water inlet of the water cup 1, so as to reduce the probability of the heater 4 being dry-burned in the later stage.

[0037] The control method of the washing machine is as follows: before water enters the water cup 1, the controller obtains the initial detection temperature T10 of the first temperature detector 5 and the initial detection temperature T20 of the second temperature detector 6. The controller enters water into the water cup 1 according to the set water entry time. After the water entry is completed, the controller obtains the real-time detection temperature T11 of the first temperature detector 5 and the real-time detection temperature T21 of the second temperature detector 6. The controller calculates the temperature change value ΔT1 of the first temperature detector 5 and the temperature change value ΔT2 of the second temperature detector 6. The controller determines whether the water level in the water cup 1 exceeds the second temperature detector 6 based on ΔT1 and ΔT2.

[0038] Specifically, if ΔT1 and ΔT2 are both greater than the set first temperature difference value, and the temperature difference between T11 and T21 is less than the set second temperature difference value, it is judged that the water level in the water cup 1 is above the second temperature detector 6; otherwise, the controller controls to actively start the heater 4 to work for the second set time, and the controller obtains the detection temperature of the first temperature detector 5 within the second set time range in real time, and calculates the temperature rise value ΔT11 of the first temperature detector 5 within the second set time range; the controller obtains the detection temperature of the second temperature detector 6 within the second set time range in real time, and calculates the temperature rise value ΔT21 of the second temperature detector 6 within the second set time range; if ΔT11 and / or ΔT21 exceed the set temperature rise threshold, it is judged that the water level of the washing machine does not exceed the second temperature detector 6; if ΔT11 and ΔT21 are both less than the set minimum temperature rise value, it is judged that the water level of the washing machine exceeds the second temperature detector 6. Through this method, it can be ensured that the water level entering the water cup 1 is above the second temperature detector 6, and the subsequent dry burning of the heater 4 can be avoided as much as possible.

[0039] The cleaning machine of the present invention is provided with temperature detectors at different heights. Based on the heights of the first temperature detector 5 and the second temperature detector 6 relative to the water suction port 22 of the volute 2 and the heater 4, the water level of the water cup 1 can be judged based on the temperature changes of the two. In this way, the water level in the water cup 1 can be understood without providing a special water level detector, which is low-cost and simplifies the structure in the water cup 1.

[0040] The control method of the cleaning machine in the present invention, without setting a water level detector, can effectively determine the water level in the water cup 1 by combining the power of the motor 3 and the temperature changes of the first temperature detector 5 and the second temperature detector 6, thereby avoiding the problem of dry burning of the heater 4.

[0041] The control method of the cleaning machine in the present invention, without providing a water level detector, can also judge whether the water intake in the water cup 1 satisfies the problem of the heater 4 burning dry during operation according to the temperature changes of the first temperature detector 5 and the second temperature detector 6, thereby ensuring the safety of the cleaning machine.

[0042] In the specification and claims of the present invention, terms indicating directions, such as "front", "rear", "up", "down", "left", "right", "side", "top", "bottom", etc., are used to describe various exemplary structural parts and elements of the present invention, but these terms are used here only for the purpose of convenience of description and are determined based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in the present invention can be arranged in different directions, these terms indicating directions are only used as explanations and should not be regarded as limitations. For example, "up" and "down" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

Claims

1. A cleaning machine, comprising a water cup (1), a volute (2) arranged in the bottom of the water cup (1), an impeller (21) arranged in the volute (2), a motor (3) arranged below the water cup (1) and connected to the impeller (21), a heater (4) arranged in the water cup (1) and below the volute (2), and a controller connected to the motor (3) and the heater (4) via electrical signals, characterized in that: The water cup (1) is provided with a first temperature detector (5) and a second temperature detector (6) which are respectively connected to the controller by electrical signals; the first temperature detector (5) is arranged at a height between the water suction port (22) at the bottom of the volute (2) and the upper surface of the heater (4); and the second temperature detector (6) is arranged at a height above the water suction port (22) of the volute (2).

2. The cleaning machine according to claim 1, characterized in that: The first temperature detector (5) and the second temperature detector (6) are fixedly arranged on the side wall of the water cup (1).

3. A control method for a cleaning machine as claimed in claim 1, characterized in that: When the cleaning machine is working, the controller obtains the power of the motor (3), and determines the relationship between the water level in the water cup (1) and the heights of the first temperature detector (5) and the second temperature detector (6) according to the power of the motor (3), and then determines whether to turn on the heating tube according to the relationship between the water level in the water cup (1) and the heights of the first temperature detector (5) and the second temperature detector (6).

4. The control method of a cleaning machine according to claim 3, characterized in that: If the fluctuation amount of the power of the motor (3) exceeds the set fluctuation range, it is determined that there is a foaming problem in the water cup (1); At this time, if the heater (4) is in the on state, the controller obtains the detection temperature of the second temperature detector (6); if the detection temperature of the second temperature detector (6) exceeds the set high temperature threshold, it is determined that the foaming in the water cup (1) is serious, and the controller controls to turn off the heater (4); otherwise, the heater (4) is kept in the on state; At this time, if the heater (4) is in an off state, the controller controls the heater (4) to be actively turned on and to work for a first set time at a set heating power; during this process, the controller obtains the detection temperature of the second temperature detector (6); if the temperature rise detected by the second temperature detector (6) exceeds the set temperature rise value within the first set time, it is determined that the water cup (1) is seriously foaming, and the controller controls water to be fed into the cleaning machine; if the temperature rise detected by the second temperature detector (6) does not exceed the set temperature rise value within the first set time, it is determined that the dynamic liquid level in the water cup (1) is between the first temperature detector (5) and the second temperature detector (6), and the controller controls the cleaning machine to turn on the heater (4) to work normally according to the working process.

5. The control method of a cleaning machine according to claim 4, characterized in that: When the temperature rise detected by the second temperature detector (6) exceeds the set temperature rise value within the first set time, the controller controls the amount of water entering the cleaning machine to be the amount of water required for the height difference between the first temperature detector (5) and the second temperature detector (6) in the water cup (1).

6. The control method of a cleaning machine according to claim 3, characterized in that: If the power of the motor (3) continues to decrease within a set time period, the controller determines that the dynamic liquid level in the water cup (1) is below the first temperature detector (5), and the controller controls the heater (4) to stop working.

7. The control method of a cleaning machine according to claim 3, characterized in that: If the fluctuation amount of the power of the motor (3) is within the set fluctuation range, it is determined that the dynamic liquid level in the water cup (1) is above the second temperature detector (6), and the controller controls the heater (4) to perform heating.

8. A control method for a cleaning machine as claimed in claim 1, characterized in that: Before water enters the water cup (1), the controller obtains an initial detection temperature T10 of the first temperature detector (5) and an initial detection temperature T20 of the second temperature detector (6); The controller fills water into the water cup (1) according to the set water filling time. After the water filling is completed, the controller obtains the real-time detection temperature T11 of the first temperature detector (5) and the real-time detection temperature T21 of the second temperature detector (6); The controller calculates a temperature change value ΔT1 of the first temperature detector (5) and a temperature change value ΔT2 of the second temperature detector (6), and determines whether the water level in the water cup (1) exceeds the second temperature detector (6) based on ΔT1 and ΔT2.

9. The control method of a cleaning machine according to claim 8, characterized in that: If ΔT1 and ΔT2 are both greater than a set first temperature difference value, and the temperature difference between T11 and T21 is less than a set second temperature difference value, it is determined that the water level in the water cup (1) is above the second temperature detector (6); otherwise, the controller actively controls the heater (4) to work for a second set time, and the controller obtains the detection temperature of the first temperature detector (5) within the second set time range in real time, and calculates the temperature rise value ΔT11 of the first temperature detector (5) within the second set time range; The controller acquires the detected temperature of the second temperature detector (6) within a second set time range in real time, and calculates the temperature rise value ΔT21 of the second temperature detector (6) within the second set time range; if ΔT11 and / or ΔT21 exceeds the set temperature rise threshold, it is judged that the water inlet level of the cleaning machine does not exceed the second temperature detector (6); if ΔT11 and ΔT21 are both less than the set minimum temperature rise value, it is judged that the water inlet level of the cleaning machine exceeds the second temperature detector (6).

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