Fire bucket and water discharge control method

Abstract

The application discloses a fire-fighting bucket and a water discharge control method. The fire-fighting bucket comprises a bucket body, a valve assembly and a connecting rod. The bottom of the bucket body is provided with a water discharge port. The valve assembly is installed above the water discharge port in the bucket and comprises a driving device and a valve plate capable of closing the water discharge port. The valve plate is provided with a distance sensor for monitoring the distance between the valve plate and the bottom of the bucket. The bucket body is provided with a pressure sensor for sensing the internal pressure. The control method pre-establishes a corresponding relationship model of the water discharge flow, the valve opening and the water pressure in the bucket. The real-time opening of the valve plate and the real-time water pressure at the bottom of the bucket are synchronously collected during water discharge. The target opening value required for maintaining the target flow is inversely calculated through the model in combination with the target constant flow value and the real-time water pressure. Then, the driving device is controlled to adjust the lifting of the valve according to the opening deviation, the flow area is dynamically adjusted, the flow change caused by the water pressure fluctuation is compensated, and constant and uniform discharge is realized.

Description

Technical Field

[0001] This invention relates to the field of fire-fighting equipment technology, and more specifically, to a fire-fighting bucket and a method for controlling water discharge. Background Technology

[0002] With the acceleration of urbanization, fires in high-rise buildings and large-span spaces are frequent. At the same time, the demand for fire prevention and control in remote areas such as forests and mountains is increasing. Traditional ground fire-fighting equipment is limited by terrain, space, and operating height, making it difficult to quickly reach the fire point and achieve efficient fire-fighting operations. With its advantages of maneuverability, fewer take-off and landing restrictions, high-altitude close-range operation, and no risk of personnel casualties, drones have become one of the core equipment in the field of emergency fire fighting. Suspended fire buckets are the core operating components of drones for carrying water for fire fighting.

[0003] In existing technologies, when drones suspend fire buckets for high-altitude firefighting, water in the buckets is discharged from the bottom. The bottom of the bucket is equipped with a valve assembly that can rotate and open around a hinge axis. The valve's drive mechanism uses a telescopic motor linked to the drone's suspension mechanism. During operation, the linear extension and retraction of the motor directly pulls the valve to rotate around the hinge axis, allowing only two states: fully open or fully closed. This completes the discharge of water from the bucket. However, existing fire bucket systems only offer two-position control (fully open / fully closed), lacking linear flow regulation capabilities. They cannot adjust the drainage flow in real time based on the fire's scale, type of fire, or operating distance, resulting in poor linear and precise control of the drainage flow and extremely poor operational adaptability. Therefore, a technical solution is needed to address these issues. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art, to control the amount of water discharged, to achieve stable control of drainage flow, to realize continuous linear adjustment and dynamic constant control of drainage flow, and to provide a fire bucket and drainage water control method.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This invention discloses a fire-fighting bucket, including a bucket body, a valve assembly, and connecting rods. The bottom of the bucket body has a drain outlet. The valve assembly is installed inside the bucket body, located above the drain outlet. The valve assembly is fixedly connected to the bottom of the bucket body via multiple connecting rods. The valve assembly includes a driving device and a valve plate. The driving device can drive the valve plate closer to or further away from the drain outlet, and the valve plate can close the drain outlet. A distance sensor is installed on the valve plate to monitor the distance between the valve plate and the bottom of the bucket body, enabling precise control of the distance between the valve plate and the bottom of the bucket body, controlling the flow area, and thus precisely adjusting the flow rate.

[0007] Furthermore, a base plate is fixedly installed on the inner bottom surface of the barrel, and the lower end of the connecting rod is fixedly connected to the base plate. The base plate includes multiple drainage holes, which are located within the vertical projection range of the valve plate. The driving device includes a rotatable threaded rod that passes through the valve plate. The lower end of the threaded rod is rotatably connected to the base plate, and the rotation of the threaded rod causes the valve plate to move closer to or away from the base plate.

[0008] Furthermore, the valve plate includes a plate body, a threaded sleeve, and a sliding sleeve. The threaded sleeve is rotatably mounted at the center of the plate body. The threaded rod passes through and is threadedly connected to the threaded sleeve. The valve plate includes multiple sliding sleeves, and the connecting rod passes through and is slidably connected to the sliding sleeves.

[0009] Furthermore, the base plate includes a central portion, and a plurality of drainage holes are arranged in a ring around the central portion, with a radially extending connecting plate formed between two adjacent drainage holes.

[0010] Furthermore, it includes a pressure sensor, which is fixedly installed at the bottom of the tank and can monitor the water pressure at the bottom of the liquid inside the tank in real time.

[0011] Furthermore, it includes an isolation cylinder, the lower end of which is fixedly installed at the bottom of the barrel body, and the pressure sensor is fixedly installed inside the isolation cylinder. The isolation cylinder has an opening located at the lower end of the side wall of the isolation cylinder, and the opening faces away from the drain outlet to prevent interference with the pressure sensor when water is discharged.

[0012] This invention also discloses a method for controlling the discharge of water from a fire-fighting bucket, based on the aforementioned fire-fighting bucket, comprising the following steps:

[0013] S1. Establish a drainage flow model for the fire bucket, wherein the drainage flow model is a model showing the relationship between drainage flow and valve opening and water pressure inside the bucket;

[0014] S2. Receive the target constant flow rate value and simultaneously collect the real-time opening value of the valve plate and the real-time water pressure value at the bottom of the tank during the drainage process.

[0015] S3. Based on the target constant flow rate and the real-time water pressure, and combined with the drainage flow rate mathematical model, the target opening value required to maintain the target constant flow rate is calculated in reverse.

[0016] S4. Based on the deviation between the target opening value and the real-time opening value, control the drive device to adjust the lifting and lowering opening of the valve plate, dynamically adjust the flow area between the valve plate and the bottom of the tank, compensate for the flow fluctuation caused by water pressure changes, and achieve constant and uniform discharge of drainage flow.

[0017] Furthermore, in step S1, the drainage flow model is established based on the annular gap radial outflow theory, and its expression is:

[0018]

[0019] in, Instantaneous drainage flow rate For the comprehensive flow coefficient, It is the acceleration due to gravity. The real-time water level head is the water level head inside the tank; the real-time water level head is calculated based on the real-time water pressure value collected by the pressure sensor through the basic equation of hydrostatic pressure. The effective flow area corresponding to the real-time opening degree is calculated using the following formula:

[0020]

[0021] in, The diameter of the valve plate. This represents the real-time opening value of the valve plate.

[0022] In step S3, the target constant flow rate value and the real-time liquid level head are substituted into the drainage flow rate model, and the target opening value required to maintain the target constant flow rate is obtained by reverse calculation.

[0023] Furthermore, the effective flow area is the cross-sectional area of ​​the annular gap between the valve plate and the base plate, and its calculation rules include three states:

[0024] when hour, ;

[0025] when hour, ;in, The controllable maximum opening threshold;

[0026] when hour, ;in, The total flow area of ​​the drainage holes. This refers to the number of drainage holes on the base plate. This represents the area of ​​a single drain hole.

[0027] Furthermore, in step S2, the real-time opening value of the valve plate and the real-time water pressure value at the bottom of the tank are collected simultaneously with a synchronous sampling period of 10ms to 50ms.

[0028] In step S4, an incremental PID control algorithm is used to generate a drive control signal with the deviation between the target opening value and the real-time opening value as the input. At the same time, the upper limit of the valve plate opening change rate is preset to limit the opening adjustment range within a single sampling period.

[0029] The beneficial effects of this invention are:

[0030] 1. The fire bucket of this invention controls the valve plate through a threaded transmission structure of a threaded rod and a threaded sleeve, converting the rotational motion of the motor into the linear lifting motion of the valve plate, thus realizing continuous linear adjustment of the valve opening and completely solving the defect of traditional flip valves that can only be fully open or fully closed. At the same time, with the real-time feedback of the opening from the distance sensor and the real-time feedback of the water pressure from the pressure sensor, combined with the pre-established flow model, it can realize closed-loop precise control of the drainage flow. It can flexibly adjust and maintain a constant drainage flow according to different fire conditions, greatly improving the operational adaptability and fire extinguishing efficiency of the fire bucket, and can be widely used in fire extinguishing operations in various scenarios such as high-rise buildings and forests and mountains.

[0031] 2. This invention uses a pressure sensor at the bottom of the tank to collect water pressure data in real time. Combined with the opening data of the distance sensor, a control system that can uniformly control the drainage volume is constructed. By pre-establishing a drainage flow model based on the radial outflow theory of the annular gap of the valve plate, the target opening value required to maintain the target flow rate can be calculated based on the real-time water pressure. It automatically compensates for water pressure changes caused by the drop in liquid level and pressure in the tank and water sloshing, so that the drainage flow rate is always stable at the set value. The constant and uniform drainage flow avoids the problems of uneven water flow and poor fire extinguishing effect when the water volume decreases during traditional bucket drainage, thus reducing water waste. Attached Figure Description

[0032] Figure 1 This is a cross-sectional view of this embodiment.

[0033] Figure 2 for Figure 1 A magnified view of a portion of the image.

[0034] Figure 3 This is a schematic diagram of the internal structure of this embodiment.

[0035] Figure 4 This is a bottom-view schematic diagram of this embodiment.

[0036] Reference numerals: 1. Barrel body; 11. Drain outlet; 111. Ring edge; 12. Bottom plate; 121. Central part; 122. Connecting plate; 123. Drain hole; 13. Ring plate; 14. Support leg; 2. Valve assembly; 21. Drive device; 211. Threaded rod; 22. Valve plate; 221. Plate body; 2211. Sliding sleeve; 222. Threaded sleeve; 23. Distance sensor; 3. Connecting rod; 4. Pressure sensor; 5. Isolation cylinder; 51. Opening. Detailed Implementation

[0037] The technical solutions in this embodiment will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] like Figures 1 to 4 As shown, this embodiment discloses a fire-fighting bucket, including a bucket body 1, a valve assembly 2, a connecting rod 3, a pressure sensor 4, and an isolation cylinder 5. The bucket body 1 is a high-strength, lightweight bucket structure with an open top and a narrow bottom. The top of the bucket body 1 is equipped with a lifting lug structure adapted for drone mounting, which can be stably suspended below the drone to perform operations. A through-hole 11 is opened at the center of the bottom of the bucket body 1 as a discharge channel for fire-fighting water inside the bucket. A ring rim 111 is formed around the 111 rim of the bucket body 1. A base plate 12 is coaxially fixedly installed on the inner bottom surface of the bucket body 1. The base plate 12 is fixedly installed on the upper end surface of the ring rim 111. A ring plate 13 is fixedly installed on the outer bottom surface of the bucket body 1. The ring plate 13 is also fixedly connected to the base plate 12 to strengthen the bottom structure of the bucket body 1 and ensure the stability of the valve assembly 2 installed at the bottom of the bucket body 1. Multiple support legs 14 are fixedly installed in a ring shape on the lower end surface of the ring plate 13 to prevent the bottom of the bucket body 1 from directly contacting the ground and to protect the valve plate 22.

[0039] The valve assembly 2 is installed in the internal cavity of the barrel 1 and is located directly above the drain outlet 11. The valve assembly 2 is fixedly connected to the inner bottom of the barrel 1 by multiple connecting rods 3 evenly distributed around the circumference. The lower end of the connecting rod 3 is fixedly connected to the bottom plate 12, and the upper end of the connecting rod 3 is fixedly connected to the valve assembly 2, forming a stable support frame to ensure that the valve assembly 2 does not shake during operation.

[0040] Valve assembly 2 includes a drive unit 21 and a valve plate 22. The drive unit 21 uses a waterproof servo motor as its power core and has forward and reverse rotation and precise axial position control functions. Its output end can drive the valve plate 22 to make linear reciprocating motion in the vertical direction, so that the valve plate 22 moves closer to or away from the drain outlet 11. The valve plate 22 is a circular plate structure with an outer diameter larger than the inner diameter of the drain outlet 11. When the valve plate 22 descends to its lowest position, it can completely cover and seal the drain outlet 11. An annular sealing gasket is installed on the lower end face of the valve plate 22 to achieve sealed water storage in the bucket. A distance sensor 23 is installed on the valve plate 22. The detection end of the distance sensor 23 faces the inner bottom surface of the bucket 1 and is used to monitor the vertical distance between the valve plate 22 and the inner bottom of the bucket 1 in real time. This distance value directly corresponds to the real-time opening degree of the valve, providing accurate opening degree feedback data for flow regulation and realizing closed-loop control of the opening degree.

[0041] The base plate 12 has multiple drainage holes 123 connected to the drain outlet 11. The base plate 12 includes a central portion 121. The lower end of the threaded rod 211 is rotatably connected to the center of the upper surface of the central portion 121. The multiple drainage holes 123 are evenly arranged in a ring around the central portion 121. A radially extending connecting plate 122 is formed between two adjacent drainage holes 123. The inner end of the connecting plate 122 is integrally formed with the central portion 121, and the outer end of the connecting plate 122 is fixedly connected to the outer ring plate of the base plate 12. This ensures the overall structural strength of the base plate 12 and allows it to withstand the impact load of the valve plate 22. The drainage flow area is maximized to avoid blockage and flow throttling problems during water discharge. All drainage holes 123 are located within the vertical projection range of the valve plate 22. The drive device 21 includes a rotatable threaded rod 211 that passes through the valve plate 22. The lower end of the threaded rod 211 is rotatably connected to the upper end face of the center part 121 of the base plate 12 through a bearing. The rotation of the threaded rod 211 causes the valve plate 22 to move closer to or further away from the base plate 12. The raising and lowering of the valve plate 22 can directly change the size of the annular gap between it and the base plate 12, thereby adjusting the effective flow area of ​​the annular gap and realizing continuous linear adjustment of the drainage flow.

[0042] The valve plate 22 includes a plate body 221, a threaded sleeve 222, and multiple sliding sleeves 2211. A mounting hole is provided at the center of the plate body 221. The threaded sleeve 222 is rotatably mounted in the mounting hole via a bearing. A threaded rod 211 passes through the threaded sleeve 222 and forms a threaded transmission engagement with it. When the threaded rod 211 rotates, it drives the threaded sleeve 222 and the plate body 221 to rise and fall vertically via the threaded transmission. Multiple sliding sleeves 2211 are also fixed on the plate body 221, evenly distributed circumferentially. The number of sliding sleeves 2211 corresponds one-to-one with the number of connecting rods 3. Each connecting rod 3 passes through one sliding sleeve 2211, and the inner wall of the sliding sleeve 2211 slides against the outer wall of the connecting rod 3, providing guidance and limiting for the rising and falling of the valve plate 22. This prevents the valve plate 22 from rotating circumferentially with the threaded rod 211, ensuring the smoothness of the rising and falling action and the accuracy of the opening control.

[0043] Pressure sensor 4 is fixedly installed at the bottom of the inner wall of the tank 1 to collect the water pressure value at the bottom of the tank 1 in real time. This pressure value can be used to calculate the real-time water level in the tank, providing water pressure feedback data for precise flow control and compensating for flow fluctuations caused by water level drops. The isolation cylinder 5 is a cylindrical structure with open top and bottom. The lower end of the isolation cylinder 5 is fixedly installed at the bottom of the tank 1. Pressure sensor 4 is fixedly installed inside the isolation cylinder 5 to protect it. An opening 51 is provided at the lower end of the side wall of the isolation cylinder 5. The opening 51 is set towards the side away from the drain outlet 11, so that water in the tank can smoothly enter the isolation cylinder 5 through the opening 51, ensuring that pressure sensor 4 can detect the water pressure in the tank normally. At the same time, it avoids the high-speed water flow disturbance generated when draining from the drain outlet 11 from directly impacting the pressure sensor 4, eliminating the influence of water flow interference on the accuracy of pressure detection and ensuring the accuracy of water pressure data.

[0044] The valve assembly 2 also houses a control unit and a rechargeable power supply. The control unit is used to receive, process, and transmit signals, and is electrically connected to the distance sensor 23, pressure sensor 4, and drive device 21. It is also equipped with a corresponding wireless signal system, enabling it to be used in conjunction with the UAV control system.

[0045] This embodiment also discloses a method for controlling the discharge of water from a fire-fighting bucket, which, based on the aforementioned fire-fighting bucket, includes the following steps:

[0046] S1. Establish a drainage flow model for the fire bucket, wherein the drainage flow model is a model showing the relationship between drainage flow and valve opening and water pressure inside the bucket;

[0047] S1.1 The drainage flow model is established based on the radial outflow theory of annular gap, and the expression is:

[0048]

[0049] in, This is the instantaneous drainage flow rate, in units of... , The comprehensive flow coefficient for the annular gap outflow is a dimensionless constant, with a stable value ranging from 0.65 to 0.72 under turbulent conditions. The effective circulation area corresponding to the real-time opening degree, in units of , For gravitational acceleration, it is usually taken as , This refers to the real-time water level head of the water in the tank relative to the reference surface of the bottom plate, in units of... The real-time water pressure value collected by the pressure sensor is obtained by conversion using the basic equation of hydrostatic pressure.

[0050] S1.2, Define the calculation rules for effective flow area: The effective flow area is the cross-sectional area of ​​the annular gap between the valve plate and the bottom plate, including three states:

[0051] when At this time, the valve plate is completely flush with the base plate, the annular gap is sealed, and the effective flow area is: ;

[0052] when At this time, the valve plate is in a linearly controllable operating condition, and the effective flow area is strictly linearly positively correlated with the opening degree: ;in, The diameter of the valve plate. This represents the real-time opening value of the valve plate. The controllable maximum opening threshold;

[0053] when At this time, the valve plate enters the flow saturation condition, and the effective flow area reaches the total flow area of ​​the drain hole and remains constant:

[0054]

[0055] in, The total flow area of ​​the drainage holes. This refers to the number of drainage holes on the base plate. This represents the area of ​​a single drain hole.

[0056] System benchmark:

[0057] Opening reference calibration: Drive the valve plate down to the closed position where it is fully in contact with the base plate, and record the value collected by the distance sensor as the zero opening reference value. The valve plate is driven to move upwards to its maximum mechanical stroke, and this is recorded as the maximum opening reference value. ; Calculate the controllable maximum opening threshold and determine This ensures linear controllability throughout the entire process.

[0058] Pressure reference calibration: With no water in the tank, continuously collect 20 sets of pressure sensor output values, and take the average value as the zero pressure reference value. Eliminate the influence of ambient atmospheric pressure.

[0059] Parameter pre-storage: Store the above mathematical model and structural constants ( , , , The initial flow coefficient, PID control parameters, sampling period, etc. are pre-stored into the control system to complete system initialization.

[0060] S2. Receive the target constant flow rate value and simultaneously collect the real-time opening value of the valve plate and the real-time water pressure value at the bottom of the tank during the drainage process.

[0061] Before firefighting operations, control targets are received; during drainage, two core feedback parameters are synchronously collected at fixed intervals and filtered.

[0062] S2.1 Initial parameter configuration before operation:

[0063] After the extinguishing medium is injected into the tank, the initial water pressure value is collected by a pressure sensor. The initial liquid level head is calculated based on the fundamental equation of hydrostatic pressure:

[0064]

[0065] in, The density of the extinguishing agent is taken as 1000 kg / m³. The extinguishing agent is generally room temperature water. 3 ;

[0066] The target constant flow rate value is received from the control system. And verify whether it is within a controllable range: calculate the maximum allowable flow. ,like The verification passes.

[0067] S2.2, Dual-parameter synchronous acquisition and filtering preprocessing:

[0068] After the drainage operation is started, two core parameters are collected simultaneously with a sampling period of 10ms to 50ms:

[0069] Real-time valve opening value acquisition: The raw valve opening value is acquired by a distance sensor on the valve plate. A median filtering algorithm is used (3 to 7 sets of data are collected continuously, and the average value is taken after removing extreme values) to eliminate sudden interference and obtain the real-time valve opening value. ( (The current sampling period number);

[0070] Real-time water pressure acquisition: Raw water pressure values ​​are acquired via a pressure sensor at the bottom of the tank. The water is first physically stabilized by an isolation cylinder, then a moving average filtering algorithm (averaging the most recent 5-20 sets) is used to eliminate interference from water sloshing and flow impact, resulting in the real-time water pressure value. ;

[0071] Real-time liquid level head is calculated based on real-time water pressure value. :

[0072] .

[0073] S3. Based on the target constant flow rate and the real-time water pressure, and combined with the drainage flow rate mathematical model, the target opening value required to maintain the target constant flow rate is calculated in reverse.

[0074] S3.1, Set the target constant flow rate value With real-time liquid level head Substituting into the drainage flow model, the target opening value required to maintain the target constant flow rate is calculated. :

[0075] ;

[0076] S3.2, Opening Amplitude Limitation: The target opening value obtained by back-calculation is limited to avoid overtravel control.

[0077] when At that time, take ;

[0078] when At that time, take .

[0079] S4. Based on the deviation between the target opening value and the real-time opening value, control the drive device to adjust the lifting and lowering opening of the valve plate, dynamically adjust the flow area between the valve plate and the bottom of the tank, compensate for flow fluctuations caused by water pressure changes, and achieve constant and uniform discharge of drainage flow. Specifically:

[0080] S4.1 Calculate the opening deviation value for the current sampling period:

[0081] ;

[0082] S4.2. Generate a drive control signal based on the opening deviation, control the drive device to drive the threaded rod to rotate in both directions, and drive the valve plate to make linear lifting and lowering motion along the connecting rod;

[0083] S4.3 The dynamic compensation logic is as follows: As drainage proceeds, the liquid level in the tank decreases and the real-time water pressure value decreases. The target opening value automatically increases linearly to compensate for the flow rate reduction caused by the drop in liquid level. When the water in the tank sloshes and causes a temporary increase in water pressure, the target opening value automatically decreases linearly to suppress the sudden increase in flow rate and always maintain a constant and uniform drainage flow rate.

[0084] In step S4, an incremental PID control algorithm is used to achieve accurate opening tracking and flow rate verification.

[0085] An incremental PID control algorithm adapted to servo motors is used to achieve zero steady-state error tracking of the opening degree, while real-time flow verification and dynamic self-correction of the model are performed to ensure control accuracy.

[0086] S4.4 Incremental PID Control Algorithm: The deviation between the target opening value and the real-time opening value is used as the input to generate a drive control signal. The calculation formula is as follows:

[0087]

[0088] in, For the first The control output increment for each sampling period corresponds to the increment of the number of step pulses of the drive motor. , , These are the proportional, integral, and derivative coefficients for PID control. and These are the opening deviation values ​​for the first two sampling periods, respectively.

[0089] S4.5, Opening Change Rate Limit: Preset upper limit of the valve plate opening change rate. The valve opening change is limited to no more than a certain amount within a single sampling period. This avoids flow fluctuations caused by sudden changes in the flow area and ensures a smooth transition of drainage flow.

[0090] S4.6 Real-time traffic verification and dynamic self-correction of the model:

[0091] Calculate the actual instantaneous drainage flow rate :

[0092]

[0093] Calculate the relative deviation of the flow rate:

[0094]

[0095] When relative deviation When the flow rate exceeds the preset allowable threshold (typically 2% to 5%), the comprehensive flow coefficient is dynamically self-corrected.

[0096]

[0097] The corrected flow coefficients were updated to all core calculation formulas to eliminate systematic errors caused by factors such as structural wear, medium changes, and ambient wind pressure.

[0098] Throughout the drainage process, the operating status of the sensors and the flight attitude of the drone are monitored in real time. When a sensor malfunction occurs or the attitude fluctuation exceeds the safety threshold, corresponding redundancy protection and flow stabilization control measures are implemented. When a stop drainage command is received, the real-time water pressure value drops to the minimum liquid level threshold (corresponding to the remaining water in the tank not exceeding 5% of the total capacity), or a malfunction occurs, the valve plate is driven down to the zero-opening closed position to completely close the drain outlet and end the drainage operation.

[0099] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for controlling the discharge of water from a fire-fighting bucket, characterized in that, Includes the following steps: S1. Establish a drainage flow model for the fire bucket. The drainage flow model is a model showing the relationship between drainage flow, valve opening, and water pressure inside the bucket. S2. Receive the target constant flow rate value and simultaneously collect the real-time opening value of the valve plate and the real-time water pressure value at the bottom of the tank during the drainage process. S3. Based on the target constant flow rate and the real-time water pressure, and combined with the drainage flow rate model, the target opening value required to maintain the target constant flow rate is calculated in reverse. S4. Based on the deviation between the target opening value and the real-time opening value, control the drive device to adjust the lifting and lowering opening of the valve plate, dynamically adjust the flow area between the valve plate and the bottom of the tank, compensate for the flow fluctuation caused by water pressure changes, and achieve constant and uniform discharge of drainage flow. In step S1, the drainage flow model is established based on the radial outflow theory of annular gap, and its expression is: in, Instantaneous drainage flow rate For the comprehensive flow coefficient, It is the acceleration due to gravity. The real-time water level head is the water level head inside the tank; the real-time water level head is calculated based on the real-time water pressure value collected by the pressure sensor through the basic equation of hydrostatic pressure. The effective flow area corresponding to the real-time opening degree is calculated using the following formula: in, The diameter of the valve plate. This represents the real-time opening value of the valve plate. The effective flow area is the cross-sectional area of ​​the annular gap between the valve plate and the bottom plate, and its calculation rules include three states: when hour, ; when hour, ;in, The controllable maximum opening threshold; when hour, ;in, The total flow area of ​​the drainage holes. This refers to the number of drainage holes on the base plate. The area of ​​a single drain hole; A base plate (12) is fixedly installed on the inner bottom surface of the barrel (1), and the lower end of the connecting rod (3) is fixedly connected to the base plate (12). The base plate (12) includes multiple drainage holes (123), which are located within the vertical projection range of the valve plate (22).

2. The method for controlling the discharge of water from a fire-fighting bucket according to claim 1, characterized in that, The fire bucket includes a bucket body (1), a valve assembly (2), a connecting rod (3), a pressure sensor (4), and an isolation cylinder (5). The bottom of the bucket body (1) is provided with a drain outlet (11). The valve assembly (2) is installed inside the bucket body (1) and is located above the drain outlet (11). The valve assembly (2) is fixedly connected to the bottom of the bucket body (1) by multiple connecting rods (3). The valve assembly (2) includes a driving device (21) and a valve plate (22). The driving device (21) can drive the valve plate (22) to move closer to or away from the drain outlet (11). The valve plate (22) can close the drain outlet (11). The valve plate (22) is equipped with a distance sensor (23). The distance sensor (23) monitors the distance between the valve plate (22) and the bottom of the bucket body (1). The lower end of the isolation cylinder (5) is fixedly installed at the bottom of the barrel body (1), and the pressure sensor (4) is fixedly installed inside the isolation cylinder (5). The isolation cylinder (5) has an opening (51), which is located at the lower end of the side wall of the isolation cylinder (5) and faces away from the drain outlet (11).

3. The method for controlling the discharge of water from a fire-fighting bucket according to claim 2, characterized in that, The drive device (21) includes a rotatable threaded rod (211) that passes through the valve plate (22). The lower end of the threaded rod (211) is rotatably connected to the base plate (12). The rotation of the threaded rod (211) causes the valve plate (22) to move closer to or away from the base plate (12).

4. The method for controlling the discharge of water from a fire-fighting bucket according to claim 3, characterized in that, The valve plate (22) includes a plate body (221), a threaded sleeve (222), and a sliding sleeve (2211). The threaded sleeve (222) is rotatably mounted at the center of the plate body (221). The threaded rod (211) passes through and is threadedly connected to the threaded sleeve (222). The valve plate (22) includes multiple sliding sleeves (2211). The connecting rod (3) passes through and is slidably connected to the sliding sleeves (2211).

5. The method for controlling the discharge of water from a fire-fighting bucket according to claim 3, characterized in that, The base plate (12) includes a central portion (121), and a plurality of drainage holes (123) are arranged in a ring around the central portion (121), with a radially extending connecting plate (122) formed between two adjacent drainage holes (123).

6. The method for controlling the discharge of water from a fire-fighting bucket according to claim 1, characterized in that, In step S2, the real-time opening value of the valve plate and the real-time water pressure value at the bottom of the tank are collected simultaneously with a synchronous sampling period of 10ms to 50ms. In step S4, an incremental PID control algorithm is used to generate a drive control signal with the deviation between the target opening value and the real-time opening value as the input. At the same time, the upper limit of the valve plate opening change rate is preset to limit the opening adjustment range within a single sampling period.

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