Disclosure of Invention
The invention aims to solve at least one of the problems in the prior related art to a certain extent, and therefore the invention provides a water shortage detection method of cooking equipment, which can accurately and reliably judge whether an evaporator is in shortage or not according to the change of working parameters of the evaporator, thereby reducing the cost.
According to the water shortage detection method of the cooking equipment, the technical scheme is as follows:
a water shortage detection method of a cooking device comprises the following steps:
s1: controlling the evaporator to start working;
s2: acquiring working parameters of an evaporator;
s3: comparing the working parameter of the evaporator with a set value;
s4: if the working parameter of the evaporator is less than or equal to the set value, timing is started and the step S5 is entered;
s5: and acquiring and judging whether the working parameters of the evaporator are continuously less than or equal to a set value within a first set time, if so, judging that the evaporator is lack of water, otherwise, returning to the step S2.
In some embodiments, further comprising the step of:
s6: if the working parameter of the evaporator is larger than the set value, starting timing and entering the step S7;
s7: and acquiring and judging whether the working parameter of the evaporator is reduced to a comparison value within a second set time, if so, judging that the evaporator is lack of water, otherwise, returning to the step S2.
In a first embodiment, the operating parameter is an operating current, and the set value is 120% to 150% of a stable and effective operating current of the evaporator during dry-burning.
Preferably, the set value is greater than the comparison value, the comparison value is 20% -40% of the steady current of the evaporator in the water process, or the comparison value is the current threshold value of the evaporator changing from water to no water.
In a second embodiment, the operating parameter is operating power, and the set value is 120% to 150% of the stable and effective operating power of the evaporator during dry-burning.
Preferably, the set value is greater than the comparison value, the comparison value is 20% -40% of the stable power of the evaporator in the water process, or the comparison value is a power threshold value for changing the evaporator from water to no water.
In some embodiments, the first set time is 2s to 3s and the second set time is 2s to 3 s.
In some embodiments, in step S1, if the water pump is started before or at the same time as the evaporator is controlled to start operating, it is determined that the water inlet system of the evaporator is abnormal while it is determined that the evaporator is short of water.
In some embodiments, in step S1, if the water pump is not activated before or while the evaporator is controlled to start operating, the water pump is activated when it is determined that the evaporator is out of water.
In some embodiments, the method further comprises step S8: and when the evaporator is judged to be lack of water, sending a reminding signal and/or controlling the evaporator to stop working.
Compared with the prior art, the invention at least comprises the following beneficial effects:
compared with the detection mode of the existing temperature sensor assembly, the detection accuracy is high, the temperature sensor assembly can be omitted, and the cost is lower.
Example 1
As shown in fig. 1-2, the invention provides a water shortage detection method for a cooking device, wherein the cooking device is any one of a steam box, a steaming and baking all-in-one machine, a baking and steaming all-in-one machine, a steaming oven, a micro-steaming box and a micro-steaming and baking all-in-one machine, the cooking device comprises an evaporator 1, a main controller 2, a water pump 3 and a timing module 4, the evaporator 1 is provided with a PTC heater 11 and an acquisition module 12 which are respectively electrically connected with the main controller 2, and the acquisition module 12 is connected with the PTC heater 11 and is used for detecting working parameters of the PTC heater 11. The main controller 2 is electrically connected to the timing module 4 for controlling the operation of the timing module 4 according to the operating state of the evaporator 1.
Preferably, the PTC heater 11 is a positive temperature coefficient ceramic body, and its resistance value becomes larger as the temperature increases. According to this principle, when water is present in the evaporator 1, the operating power or operating current of the PTC heater 11 is substantially stabilized since the boiling evaporation temperature of water is substantially fixed at about 100 ℃; when the water in the evaporator 1 is quickly dried or has no water, the working power or the working current of the PTC heater 11 is obviously reduced due to the temperature rise in the evaporator 1, and according to the characteristic, whether the evaporator 1 is lack of water can be accurately judged through the change of the working power or the working current of the PTC heater 11.
In addition, the water inlet system of evaporator 1 includes water tank 5, inlet tube (not shown in the figure) and water pump 3, and the both ends of inlet tube communicate water tank 5 and evaporator 1 respectively, and water pump 3 sets up on the inlet tube and is connected with main control unit 2 electricity, and main control unit 2 is used for opening or closing according to cooking equipment's control command come control water pump 3 to the realization starts water pump 3 and comes to carry out the moisturizing for evaporator 1.
As shown in fig. 1, further, the water shortage detection method includes the steps of:
s1: controlling the evaporator 1 to start working;
specifically, the PTC heater 11 is controlled to operate to heat the water in the evaporator 1 to boiling, and steam required for cooking is produced.
S2: acquiring working parameters of the evaporator 1;
specifically, the acquiring module 12 acquires the operating parameters of the PTC heater 11 and sends the detected operating parameters to the main controller 2, so that the main controller 2 performs corresponding logic control according to the acquired operating parameters. Preferably, the operating parameter is an operating current or an operating power.
S3: comparing the working parameters of the evaporator 1 with set values;
specifically, the main controller 2 compares the acquired operating parameter with a set value according to the acquired operating parameter of the PTC heater 11.
S4: if the working parameter of the evaporator 1 is not more than the set value, timing is started and the step S5 is entered;
specifically, if the operating parameter of the PTC heater 11 is less than or equal to the set value, it may be preliminarily determined that the evaporator 1 is in short of water, and the timing module 4 starts timing at the same time to record the accumulated time length during which the operating parameter of the PTC heater 11 is continuously less than or equal to the set value.
S5: and acquiring and judging whether the working parameters of the evaporator 1 are continuously less than or equal to a set value within a first set time, if so, judging that the evaporator 1 is lack of water, otherwise, returning to the step S2.
Specifically, whether the working parameter of the PTC heater 11 is continuously less than or equal to a set value within a first set time is obtained and judged, that is, whether the accumulated duration of the working parameter of the PTC heater 11 continuously less than or equal to the set value is greater than or equal to the first set time, if so, the evaporator 1 is indicated to be dried up or no water is in the evaporator 1, at this time, the evaporator 1 is judged to be lack of water, and the timing of the timing module 4 is cleared; if not, the water in the evaporator 1 is indicated, at this time, the timing of the timing module 4 is cleared and the process returns to step S2, so as to perform the next cycle judgment.
It can be seen that, according to the method for detecting water shortage of the cooking device of the present embodiment, by detecting the change of the operating parameter of the evaporator 1 (i.e. the PTC heater 11), the characteristic that when the water in the evaporator 1 is quickly dried or has no water, the operating power or the operating current of the PTC heater 11 is obviously reduced is fully utilized, and whether the evaporator 1 is in water shortage or not is accurately and reliably determined.
As shown in fig. 1, further, the water shortage detection method further includes the steps of:
s6: if the working parameter of the evaporator 1 is larger than the set value, timing is started and the process goes to step S7;
specifically, if the operating parameter of the PTC heater 11 is greater than the set value, it may be preliminarily determined that the evaporator 1 is out of water, and the timing module 4 starts timing to record the time period for which the operating parameter of the PTC heater 11 falls to the comparison value.
S7: and acquiring and judging whether the working parameter of the evaporator 1 is reduced to the comparison value within the second set time, if so, judging that the evaporator 1 is lack of water, otherwise, returning to the step S2.
Specifically, if the comparison value is smaller than the set value, obtaining and judging whether the working parameter of the PTC heater 11 drops to the comparison value within a second set time, if so, indicating that the evaporator 1 changes from water burst to no water, at this time, judging that the evaporator 1 is in water shortage, and resetting the timing of the timing module 4; if not, the water in the evaporator 1 is indicated, at this time, the timing of the timing module 4 is cleared and the process returns to step S2, so as to perform the next cycle judgment.
Therefore, when the working parameter of the PTC heater 11 is greater than the set value, whether the working parameter of the PTC heater 11 drops to the comparison value within the second set time is obtained and judged, so that whether the evaporator 1 is suddenly changed from water to no water is accurately judged, that is, the evaporator 1 is accurately judged to trigger the dry-fire water replenishing condition, and the accuracy and reliability of judging the water shortage of the evaporator 1 are improved.
Preferably, the operating parameter of this embodiment is an operating current, and the set value is 120% to 150% of a stable and effective operating current in a dry-burning process of the evaporator 11. The set value is greater than the comparison value, the comparison value is 20% -40% of the stable current of the evaporator 1 in the water process, or the comparison value is the current threshold value of the evaporator 1 which is changed from water to no water. Thereby, it is realized that whether or not the evaporator 1 is short of water is accurately and reliably judged according to the change of the operating current of the evaporator 1 (i.e., the PTC heater 11).
Preferably, the first set time is 2s to 3s, and the second set time is 2s to 3s, so that whether the operating parameter of the PTC heater 11 is continuously less than or equal to the set value or whether the operating parameter of the PTC heater 11 is decreased to the comparison value is obtained and determined within 2s to 3s, thereby ensuring that whether the evaporator 1 is in water shortage can be accurately and reliably determined within a short time, and improving the response time of water shortage determination.
Specifically, in step S1, if the water pump is started before or at the same time as the control of the operation of the evaporator 1 is started, it may be determined that the water intake system of the evaporator 1 is abnormal while it is determined that the evaporator 1 is short of water. Wherein, the water inlet system abnormity of the evaporator 1 can be at least one of the faults of the water pump 3, the water shortage of the water tank 5 and the blockage of the water inlet pipe.
Specifically, in step S1, if the water pump is not started before or while the evaporator 1 is controlled to start operating, the water pump is started when it is determined that the evaporator 1 is in a water shortage state, so as to replenish water for the evaporator 1, and avoid the evaporator 1 from being burned dry to trigger an over-temperature protection condition, which is beneficial to further prolonging the service life of the evaporator 1 and the PTC heater 11.
As shown in fig. 1, further, the water shortage detection method further includes step S8: and when the evaporator 1 is judged to be lack of water, sending a reminding signal and/or controlling the evaporator 1 to stop working.
Specifically, the cooking equipment further comprises an alarm module 6, wherein the alarm module 6 is electrically connected with the main controller 2 and used for making a sound or sending a reminding signal of light to remind a user that the evaporator 1 is in water shortage when the evaporator 1 is in water shortage. In addition, in step S1, if the water pump is started before or at the same time of controlling the evaporator 1 to start operating, it is determined that the evaporator 1 is out of water and the water inlet system of the evaporator 1 is abnormal, at this time, the alarm module 6 sends a warning signal to warn the user, and at the same time, the main controller 2 controls the PTC heater 11 to stop operating, so as to avoid the internal temperature of the evaporator 1 from being too high.
In step S1, if the water pump is not started before or while the evaporator 1 is controlled to start working, the main controller 2 may automatically control the water pump to start when it is determined that the evaporator 1 is in a water shortage state, so as to automatically replenish water to the evaporator 1, and simultaneously control the alarm module 6 to send out a reminding signal to remind a user.