Cleaning Machine and Its Detection System for Water Flow

Abstract

The present invention discloses a cleaning machine and a water flow detection system thereof, wherein the water flow detection system includes a water flow sensor and a processor electrically connected to the water flow sensor; the water flow sensor is used to detect the water flow, and the water flow is characterized by flow pulses; the processor is used to determine a first number of normal pulses and a second number of abnormal pulses in the flow pulses, and judge whether it is necessary to correct the water flow detected by the water flow sensor based on the first number and the second number, and correct the water flow if the judgment result is yes. The present invention determines the first number and the second number by the processor, judges whether it is necessary to correct the water flow detected by the water flow sensor, and corrects the water flow if the judgment result is yes, thereby obtaining a water flow that better reflects the actual water flow situation and improving the accuracy of water flow detection.

Description

Technical Field

[0001] The present invention relates to the field of water flow detection, in particular to a cleaning machine and a water flow detection system thereof. Background Art

[0002] Washing machine water flow sensors typically use the Hall effect to detect water flow. When water flows through a turbine, it drives a magnetic rotor, generating a rotating magnetic field of varying polarity. This magnetic field cuts through the magnetic induction lines, producing high and low pulse levels. The water flow rate is calculated by counting these pulses and combining them with the sensor's nominal water volume and the pulses.

[0003] Since there are many metal parts in the cleaning machine, metal parts are prone to magnetism, which leads to inaccurate detection of flow pulses by the water flow sensor due to the influence of the magnetism of the metal parts when detecting the water flow of the cleaning machine. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defect of inaccurate flow pulse detection in the prior art and to provide a cleaning machine and a water flow detection system thereof.

[0005] The present invention solves the above technical problems through the following technical solutions:

[0006] First, the present invention provides a water flow detection system, the water flow detection system comprising a water flow sensor and a processor electrically connected to the water flow sensor;

[0007] The water flow sensor is used to detect water flow, and the water flow is represented by flow pulses;

[0008] The processor is used to determine a first number of normal pulses and a second number of abnormal pulses in the flow pulses, and judge whether it is necessary to correct the water flow detected by the water flow sensor based on the first number and the second number, and correct the water flow if the judgment result is yes.

[0009] Preferably, the processor includes a determination unit, and the determination unit is electrically connected to the water flow sensor;

[0010] The determining unit receives the flow pulse, compares the pulse width of the flow pulse with a comparison condition, and determines that the corresponding flow pulse is a normal pulse if the pulse width meets the comparison condition; otherwise, determines that the corresponding flow pulse is an abnormal pulse.

[0011] Preferably, the processor further comprises a cache unit;

[0012] The cache unit is used to store the pulse width of the normal pulse in a normal cache area to determine the first number;

[0013] The cache unit is further configured to store the pulse width of the abnormal pulse in an abnormal cache area to determine the second number.

[0014] Preferably, the processor further includes a judgment unit;

[0015] The judgment unit is configured to determine that the water flow rate detected by the water flow sensor needs to be corrected if it is determined that the abnormal buffer area is full before the normal buffer area and the standard deviation of the pulse width in the abnormal buffer area is greater than or equal to a preset standard deviation, or if the normal buffer area is full before the abnormal buffer area;

[0016] The judgment unit is further configured to determine that the water flow detected by the water flow sensor does not need to be corrected when the abnormal buffer area is full before the normal buffer area and the standard deviation of the pulse width in the abnormal buffer area is less than a preset standard deviation.

[0017] Preferably, the processor further comprises a correction unit;

[0018] The correction unit is used to determine the water flow rate corresponding to the average pulse width of the normal pulse and the total water flow rate corresponding to the total pulse width of the abnormal pulse based on the pulse width of the normal pulse and the pulse width of the abnormal pulse and the correspondence between the pulse width and the water flow rate, and determine the water flow rate correction value based on the water flow rate average and the total water flow rate corresponding to the total pulse width; wherein the water flow rate correction value is used to correct the water flow rate detected by the water flow rate sensor, the water flow rate correction value is the difference between the product value and the total water flow rate, the product value is the product of the ratio and the water flow rate average, and the ratio is the ratio of the total pulse width to the pulse width average.

[0019] Preferably, the processor further comprises a correction unit;

[0020] The correction unit is used to determine the water flow average corresponding to the pulse width average of the normal cache area and the first water flow corresponding to the first pulse width stored in the abnormal cache area according to the correspondence between the pulse width and the water flow when the corrected water flow is less than or equal to the preset total water flow; and determine the water flow correction value according to the water flow average and the first water flow corresponding to the first pulse width; wherein the water flow correction value is used to correct the water flow detected by the water flow sensor, the water flow correction value is the difference between the product value and the first water flow, the product value is the product of the ratio and the water flow average, and the ratio is the ratio of the first pulse width to the pulse width average.

[0021] Preferably, the correction unit is further used to determine the corrected water flow rate as the sum of the water flow rate detected by the water flow rate sensor and the water flow rate correction value.

[0022] Preferably, twice the length of the normal buffer zone is smaller than the length of the abnormal buffer zone, and the sum of three times the length of the abnormal buffer zone and the length of the normal buffer zone is smaller than the total number of flow pulses of a preset water flow rate.

[0023] Secondly, the present invention provides a cleaning machine, which includes the above-mentioned water flow detection system, and the water flow sensor is arranged at the water inlet of the cleaning machine.

[0024] Preferably, the cleaning machine further comprises a controller; the controller is electrically connected to the processor;

[0025] The controller is used to send a water inlet end signal when determining that the corrected water flow rate is greater than the preset total water flow rate, so as to control the cleaning machine to stop water inlet.

[0026] The positive progress effect of the present invention is:

[0027] The present invention determines the first quantity and the second quantity through a processor, judges whether the water flow detected by the water flow sensor needs to be corrected, and corrects the water flow if the judgment result is yes, thereby obtaining a water flow that can better reflect the actual water flow situation and improving the accuracy of detecting the water flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of flow pulses detected by a water flow sensor without interference;

[0029] Figure 2 Schematic diagram of flow pulses detected by a water flow sensor in the presence of interference;

[0030] Figure 3 A structural diagram of a water flow detection system provided in Example 1 of the present invention;

[0031] Figure 4 A structural diagram of another water flow detection system provided in Example 1 of the present invention;

[0032] Figure 5 Schematic diagram of the pulse width when the pulse is a falling edge in Example 1 of the present invention;

[0033] Figure 6 This is a structural diagram of a cleaning machine provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0034] In order to better understand this embodiment, the following first describes the overview of this embodiment:

[0035] Figure 1 The figure schematically shows the flow pulses detected by the water flow sensor in the absence of other magnetic field interference, which are manifested as regular continuous high level and continuous low level.

[0036] Figure 2 The figure schematically shows the flow pulses detected by the water flow sensor in the presence of other magnetic field interference. The voltage pulses output by the water flow sensor may experience pulse loss, which is mainly manifested as irregular continuous high level and continuous low level.

[0037] In the existing water flow pulse calculation method, the water flow is usually calculated by counting the pulse jump edge (such as the rising edge or the falling edge), that is, counting the jump edge of each pulse and then converting it into water flow. Figure 2 In the case of abnormal flow pulses, the technology that can lose pulses can cause a discrepancy between the total water flow measured by the water flow sensor and the actual water flow. If water inflow is controlled by timing, the real-time fluctuations in water pressure and the resulting water flow per unit time can lead to inaccurate flow calculations.

[0038] In view of this, this embodiment proposes a water flow detection system. Specifically, the processor analyzes the pulse width of the Hall sensor (i.e., the water flow sensor) to determine whether the water flow detected by the Hall sensor is interfered with by the environmental magnetic field. If the water flow detected by the Hall sensor is interfered with, the water flow is corrected.

[0039] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples.

[0040] Example 1

[0041] This embodiment provides a water flow detection system that can be applied to different application scenarios, such as water inlet detection of a washing machine, water outlet detection of a dishwasher, water outlet detection of a water heater, etc. Figure 3 , the water flow detection system includes a water flow sensor 31 and a processor 32 electrically connected to the water flow sensor 31;

[0042] The water flow sensor 31 is used to detect the water flow, which is represented by flow pulses;

[0043] The processor 32 is used to determine the first number of normal pulses and the second number of abnormal pulses in the flow pulse, and judge whether the water flow detected by the water flow sensor 31 needs to be corrected based on the first number and the second number, and correct the water flow if the judgment result is yes.

[0044] In this embodiment, the processor 32 determines the first quantity and the second quantity, and determines whether the water flow detected by the water flow sensor 31 needs to be corrected. If the judgment result is yes, the water flow is corrected to obtain a water flow that can better reflect the actual water flow situation, thereby improving the accuracy of detecting the water flow.

[0045] In one embodiment, see Figure 4 , the processor 32 includes a determination unit 321, and the determination unit 321 is electrically connected to the water flow sensor 31;

[0046] The determination unit 321 receives a flow pulse, and compares the pulse width of the flow pulse with a comparison condition. If the pulse width meets the comparison condition, the determination unit 321 determines that the corresponding flow pulse is a normal pulse; otherwise, the determination unit 321 determines that the corresponding flow pulse is an abnormal pulse.

[0047] The comparison condition can be set according to actual needs. The pulse width of the flow pulse can be compared with a value or a range.

[0048] In this embodiment, each pulse is represented by a falling edge. It should be understood that in other embodiments, each pulse can also be represented by a rising edge.

[0049] Figure 5 t1, t2, t3, t4, t5, t6, and t7 schematically illustrate the pulse width of each flow pulse when the pulse is a falling edge.

[0050] Among them, the flow pulse state can be determined based on whether a continuous high level and a continuous low level are maintained within the corresponding preset time period. When a continuous high level and a continuous low level are maintained, the corresponding flow pulse is determined to be a normal pulse. When a continuous high level and a continuous low level cannot be maintained, the corresponding flow pulse state is determined to be an abnormal pulse.

[0051] For example: If the pulse width t α (α≥1, and α is an integer) is less than or equal to the preset value, then t α The corresponding flow pulse is a normal pulse; if t α If it is greater than the preset value, t α The corresponding flow pulse is an abnormal pulse, and the preset value can be set according to actual needs.

[0052] For example: the pulse width t1 of the first flow pulse and the pulse width t2 of the second flow pulse adjacent to it. (Preferably, ε>1.5), then the flow pulses corresponding to t1 and t2 are normal pulses; when or The flow pulse corresponding to the smaller pulse width between t1 and t2 is a normal pulse, and the flow pulse corresponding to the larger pulse width between t1 and t2 is an abnormal pulse.

[0053] For the pulse width ti of the nth flow pulse (i≥3, and i is an integer), by calculating the mean value X of the non-zero pulse width of the normal pulse, when the next single pulse time interval ti satisfies When ti is set, the flow pulse corresponding to ti is a normal pulse, otherwise it is an abnormal pulse.

[0054] The determining unit 321 is further configured to determine the first quantity and the second quantity according to the comparison result.

[0055] In this embodiment, the determination unit 321 quickly determines whether the flow pulse is inconsistent with the water flow law by limiting the comparison condition of the pulse width, and divides the flow pulse into normal pulses and abnormal pulses, thereby improving the efficiency of judging whether the water flow detected by the water flow sensor 31 needs to be corrected.

[0056] In one embodiment, see Figure 4 , the processor further includes a cache unit 322;

[0057] The buffer unit 322 is configured to store the pulse width of the normal pulse into a normal buffer area to determine the first quantity;

[0058] The cache unit 322 is further configured to store the pulse width of the abnormal pulse in the abnormality cache area to determine the second number.

[0059] In an optional embodiment, twice the length of the normal buffer zone is less than the length of the abnormal buffer zone, and the sum of three times the length of the abnormal buffer zone and the length of the normal buffer zone is less than the total number of flow pulses of the preset water flow rate.

[0060] Among them, the preset water flow rate is the total water flow rate corresponding to water inflow or outflow at the minimum water flow rate. When the water flow rate is less than the minimum water flow rate, a water shortage alarm will be generated.

[0061] The length of the exception buffer is set to be larger than the length of the normal buffer to prevent it from filling up prematurely. In practice, when packet loss is frequent, there may be a ratio of one normal data point to two abnormal data points. Therefore, setting the length of the normal buffer to twice the length of the exception buffer is important to ensure accurate water flow identification even when there are a large number of abnormal data points.

[0062] However, if the length of the abnormal buffer area is too large, the water flow rate may reach the set total water flow rate, but both the abnormal buffer area and the normal buffer area are not full, and it is impossible to determine whether the water flow rate detected by the water flow sensor 31 needs to be corrected. Therefore, the sum of three times the length of the abnormal buffer area and the length of the normal buffer area is limited to less than the total number of flow pulses of the preset water flow rate.

[0063] In this embodiment, the pulse width of the normal pulse is stored in the normal buffer area, and the pulse width of the abnormal pulse is stored in the abnormal buffer area. When the water flow detected by the water flow sensor 31 needs to be corrected, the processor 32 can extract the correction data to improve the correction efficiency; the length of the normal buffer area and the length of the abnormal buffer area are limited, so that the water flow detected by the water flow sensor 31 can be corrected within a reasonable time range.

[0064] In one embodiment, see Figure 4 The processor 32 further includes a judgment unit 323, which is configured to determine that the water flow rate detected by the water flow sensor needs to be corrected when it is determined that the abnormal buffer area is full before the normal buffer area and the standard deviation of the pulse width in the abnormal buffer area is greater than or equal to the preset standard deviation, or when the normal buffer area is full before the abnormal buffer area;

[0065] The judgment unit 323 is further configured to determine that the water flow detected by the water flow sensor does not need to be corrected when the abnormal buffer is full before the normal buffer and the standard deviation of the pulse width in the abnormal buffer is less than a preset standard deviation.

[0066] Among them, the preset standard deviation is set according to actual needs.

[0067] Among them, the standard deviation is used to characterize the fluctuation of the pulse width in the abnormal buffer area. If the standard deviation is greater than or equal to the preset standard deviation, it means that the fluctuation is large, and the water flow detected by the water flow sensor 31 is less than the actual water flow due to the environmental magnetic field. The water flow detected by the water flow sensor 31 needs to be corrected. Otherwise, no correction is required.

[0068] Here is a formula for calculating the standard deviation:

[0069]

[0070] Where σ is the standard deviation, t1, t2…tw represent the pulse widths in the abnormal buffer, w is an integer, and X′ represents the mean of the pulse widths in the abnormal buffer.

[0071] In this embodiment, the judgment unit 323 first determines which of the normal buffer and the abnormal buffer is full first. If the normal buffer is full first, it indicates that the pulse width data in the abnormal buffer is an abnormal pulse width caused by the influence of the environmental magnetic field, and the water flow detected by the water flow sensor 31 is corrected. If the abnormal buffer is full first, it is then determined whether the standard deviation of the pulse width in the normal buffer exceeds a preset standard deviation. If it does, it indicates that the abnormal pulse fluctuation is large and the water flow detected by the water flow sensor 31 needs to be corrected. If it does not, it indicates that the abnormal pulse fluctuation is normal. The difference in pulse width data between the normal and abnormal buffers is not due to a malfunction caused by the environmental magnetic field, but rather due to a difference caused by the momentary opening and closing of the valve or a sudden change in flow rate. Therefore, the water flow detected by the water flow sensor 31 is not corrected. In this embodiment, the judgment unit 323 determines whether to correct the water flow detected by the water flow sensor 31, which can prevent erroneous correction of the water flow detected by the water flow sensor 31. Therefore, the water flow detected by the water flow sensor 31 is corrected only when correction is required, thereby improving correction efficiency.

[0072] In one embodiment, see Figure 4 , the processor 32 further includes a correction unit 324;

[0073] The correction unit 324 is used to determine the water flow rate corresponding to the average pulse width of the normal pulse and the total water flow rate corresponding to the total pulse width of the abnormal pulse based on the pulse width of the normal pulse and the pulse width of the abnormal pulse and the correspondence between the pulse width and the water flow rate, and determine the water flow rate correction value based on the water flow rate average and the total water flow rate corresponding to the total pulse width; wherein the water flow rate correction value is used to correct the water flow rate detected by the water flow rate sensor, the water flow rate correction value is the difference between the product value and the total water flow rate, the product value is the product of the ratio and the water flow rate average, and the ratio is the ratio of the total pulse width to the pulse width average.

[0074] The following is a derivation process of the corresponding relationship between pulse width and water flow:

[0075] In order to overcome the errors caused by different water flow sensors 31, different application scenarios and different assembly conditions, under laboratory conditions, the water flow sensor 31 used can be calibrated for water flow at different water flow rates.

[0076] The specific calibration method is: under different water flow rates and set pulses, the water flow rate is calibrated by the controller. The range of water flow rate (v) is [V1, V2], where V1 is the set minimum water flow rate. If it is less than V1, a water shortage alarm will be generated. V2 is the water flow rate under the commonly used maximum water pressure. Under the condition of water flow rate (v), when N pulses are measured, the total water flow rate is M, and the total pulse width is T. Then the water flow rate represented by the unit flow pulse is Multiple (v, k) values are obtained at the water flow velocity (v). After polynomial fitting, the following quadratic curve relationship is obtained, see formula (1):

[0077] k=av 2 +bv+c (1).

[0078] Among them, a, b, and c are constant coefficients.

[0079] Then from the total water flow M=v*T=k*N, we can infer that (T / N is the pulse width of the unit flow pulse, hereinafter represented by t), which is as shown in the following formula (2):

[0080] v*t=k (2).

[0081] From formula (1) and formula (2), the relationship between the water flow rate k represented by a unit pulse and the pulse width t of a single pulse can be deduced as follows:

[0082]

[0083] Combining the experimental data, we can get a unique solution, assuming that the relationship between k and t is

[0084]

[0085] Furthermore, the following formula (3) that characterizes the corresponding relationship between pulse width and water flow rate (hereinafter referred to as k(t)) can be obtained:

[0086]

[0087] In conjunction with k(t), the following describes the specific steps of determining the water flow correction value by the correction unit 324 in this embodiment:

[0088] Determine the mean value of the pulse width of the normal pulses in the normal buffer as X, and substitute X into k(t) to obtain k(X) (i.e., the mean water flow rate); determine the total water flow rate corresponding to the pulse width of the abnormal pulse [t1, t2…tj] as [k(t1), k(t2),…, k(tj)], where t1, t2…tj represent the pulse widths of all single pulses of the abnormal pulses and j is an integer; calculate the sum of all pulse widths of the abnormal pulses as tΣ (i.e., the total pulse width of the abnormal pulses), and the water flow correction value is:

[0089] In this embodiment, the correction unit 324 uses the average water flow rate of the normal pulse to correct the water flow rate of the abnormal pulse, thereby specifically correcting the water flow rate corresponding to the abnormal pulse caused by the influence of the magnetic field, thereby improving the correction efficiency.

[0090] In one embodiment, the correction unit 324 is used to determine the water flow average corresponding to the pulse width average of the normal cache area and the first water flow corresponding to the first pulse width stored in the abnormal cache area based on the correspondence between the pulse width and the water flow when the corrected water flow is less than or equal to the preset total water flow; and determine the water flow correction value based on the water flow average and the first water flow corresponding to the first pulse width; wherein the water flow correction value is used to correct the water flow detected by the water flow sensor, the water flow correction value is the difference between the product value and the first water flow, the product value is the product of the ratio and the water flow average, and the ratio is the ratio of the first pulse width to the pulse width average.

[0091] In conjunction with k(t), the following describes the specific steps of determining the water flow correction value by the correction unit 324 in this embodiment:

[0092] Determine the mean value of the pulse width of the normal pulse as X, substitute X into k(t) to obtain k(X) (i.e., the mean water flow rate); determine the first water flow rate corresponding to the first pulse width t1 in the abnormal buffer area as k(t1); then the water flow correction value is:

[0093] In this embodiment, the correction unit 324 adopts a method similar to sliding filtering. When the water flow detected by the corrected water flow sensor 31 has not reached the desired final water flow (preset total water flow), the first water flow of the abnormal pulse is directly corrected. Because the water flow corresponding to the first abnormal pulse can better reflect the current water flow trend, rather than being affected by the previous water flow trend, the water flow corresponding to the abnormal pulse caused by the influence of the magnetic field can be corrected more specifically, thereby improving the correction efficiency.

[0094] In one embodiment, the correction unit 324 is further configured to determine the corrected water flow rate as the sum of the water flow rate detected by the water flow rate sensor and the water flow rate correction value.

[0095] If the water flow rate detected by the water flow sensor 31 before correction is K, and the water flow rate detected by the water flow sensor 31 after correction is Ktmp, the water flow correction value is K. 修正 , then Ktmp=K+K 修正 .

[0096] In this embodiment, the correction unit 324 can determine the water flow detected by the corrected water flow sensor 31 through the water flow correction value and the water flow detected by the water flow sensor 31 before correction, thereby reducing the water flow corresponding to the abnormal pulse affected by the magnetic field and improving the accuracy of the water flow detected by the water flow sensor 31.

[0097] Example 2

[0098] This embodiment provides a cleaning machine. Figure 6 The cleaning machine includes the above-mentioned water flow detection system, and the water flow sensor 31 in the water flow detection system is arranged at the water inlet of the cleaning machine.

[0099] It should be noted that the implementation method and technical effects of the water flow detection system in the cleaning machine of this embodiment can refer to the corresponding parts of Example 1 and will not be repeated here.

[0100] In one embodiment, see Figure 6 , the cleaning machine further includes a controller 61; the controller 61 is electrically connected to the processor 32;

[0101] The controller 61 is used to send a water inlet end signal when it determines that the corrected water flow rate is greater than the preset total water flow rate, so as to control the cleaning machine to stop water inlet.

[0102] Among them, the preset total water volume is set according to actual needs.

[0103] In this embodiment, after receiving the signal that the corrected water flow rate is greater than the preset total water volume, the controller 61 sends a water inlet end signal, thereby stopping the water inlet to the cleaning machine, thereby achieving the effect of saving resources.

[0104] Although specific embodiments of the present invention have been described above, those skilled in the art will appreciate that these are merely illustrative and that the scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, and such changes and modifications are intended to fall within the scope of the present invention.

Claims

1. A water flow detection system, characterized in that: The water flow detection system includes a water flow sensor and a processor electrically connected to the water flow sensor; The water flow sensor is used to detect water flow, and the water flow is represented by flow pulses; The processor is configured to determine a first number of normal pulses and a second number of abnormal pulses in the flow pulses, determine whether the water flow detected by the water flow sensor needs to be corrected based on the first number and the second number, and correct the water flow if the judgment result is yes; The processor includes a cache unit and a judgment unit; The cache unit is used to store the pulse width of the normal pulse in a normal cache area to determine the first number; The cache unit is further configured to store the pulse width of the abnormal pulse into an abnormality cache area to determine the second number; The judgment unit is configured to determine that the water flow rate detected by the water flow sensor needs to be corrected if it is determined that the abnormal buffer area is full before the normal buffer area and the standard deviation of the pulse width in the abnormal buffer area is greater than or equal to a preset standard deviation, or if the normal buffer area is full before the abnormal buffer area; The judgment unit is further configured to determine that the water flow detected by the water flow sensor does not need to be corrected when the abnormal buffer area is full before the normal buffer area and the standard deviation of the pulse width in the abnormal buffer area is less than a preset standard deviation.

2. The water flow detection system according to claim 1, characterized in that: The processor includes a determination unit, and the determination unit is electrically connected to the water flow sensor; The determining unit receives the flow pulse, compares the pulse width of the flow pulse with a comparison condition, and determines that the corresponding flow pulse is a normal pulse if the pulse width meets the comparison condition; otherwise, determines that the corresponding flow pulse is an abnormal pulse.

3. The water flow detection system according to claim 1, characterized in that: The processor further includes a correction unit; The correction unit is used to determine the water flow rate average corresponding to the pulse width average of the normal pulse and the total water flow rate corresponding to the total pulse width of the abnormal pulse based on the pulse width of the normal pulse and the pulse width of the abnormal pulse and the correspondence between the pulse width and the water flow rate, and determine the water flow rate correction value based on the water flow rate average and the total water flow rate corresponding to the total pulse width; wherein the water flow rate correction value is used to correct the water flow rate detected by the water flow rate sensor, the water flow rate correction value is the difference between the product value and the total water flow rate, the product value is the product of the ratio and the water flow rate average, and the ratio is the ratio of the total pulse width to the pulse width average.

4. The water flow detection system according to claim 1, wherein: The processor further includes a correction unit; The correction unit is configured to determine, based on the correspondence between the pulse width and the water flow rate, a water flow rate average corresponding to the pulse width average of the normal buffer area and a first water flow rate corresponding to the first pulse width first stored in the abnormal buffer area when the corrected water flow rate is less than or equal to the preset total water flow rate; And determine a water flow correction value based on the water flow mean and the first water flow corresponding to the first pulse width; wherein, the water flow correction value is used to correct the water flow detected by the water flow sensor, and the water flow correction value is the difference between the product value and the first water flow, the product value is the product of the ratio and the water flow mean, and the ratio is the ratio of the first pulse width to the pulse width mean.

5. The water flow detection system according to any one of claims 3 or 4, characterized in that: The correction unit is further configured to determine the corrected water flow rate as the sum of the water flow rate detected by the water flow rate sensor and the water flow rate correction value.

6. The water flow detection system according to claim 1, characterized in that: Twice the length of the normal buffer zone is less than the length of the abnormal buffer zone, and the sum of three times the length of the abnormal buffer zone and the length of the normal buffer zone is less than the total number of flow pulses of a preset water flow rate.

7. A cleaning machine, characterized in that: The cleaning machine includes the water flow detection system according to any one of claims 1 to 6, and the water flow sensor is arranged at the water inlet of the cleaning machine.

8. The cleaning machine according to claim 7, wherein: The cleaning machine further includes a controller; the controller is electrically connected to the processor; The controller is used to send a water inlet end signal when determining that the corrected water flow rate is greater than the preset total water flow rate, so as to control the cleaning machine to stop water inlet.

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