Fire fighting system assembly, foam proportion control method thereof and fire fighting equipment

Abstract

The invention belongs to the technical field of fire fighting equipment and provides a fire fighting system assembly, a foam proportion control method thereof and fire fighting equipment. The foam proportion control method of the fire extinguishing system assembly comprises the steps that the actual demand flow of foam is obtained; the rotating speed of a foam pump in the foam supply system is adjusted, so that the difference value between the theoretical output flow and the actual demand flow of the foam pump is a positive number and is smaller than a first preset value; and the opening degree of a backflow pipeline of the foam supply system is adjusted till the absolute value of the difference value between the actual output flow and the actual demand flow of the foam supply system is smaller than a second preset value. The output flow of the foam pump is roughly adjusted by changing the rotating speed of the foam pump, then the output flow of the foam pump is finely adjusted within a small range by changing the opening degree of the backflow pipeline, and foam output can be accurately adjusted to a proper proportion within a short time through cooperation of rough adjustment and fine adjustment.

Description

Technical Field

[0001] The present invention belongs to the technical field of fire fighting equipment, and in particular relates to a fire fighting system assembly and a foam proportion control method thereof, and fire fighting equipment. Background Art

[0002] For the fire extinguishing system of a fire truck, adding a suitable proportion of foam to the sprayed fire water can quickly control the fire, prevent the fire from spreading, and effectively improve the fire extinguishing efficiency.

[0003] The existing fire extinguishing system of fire trucks generally relies on the high-speed flow of fire water through the venturi tube to generate negative pressure, thereby sucking the foam in the foam tank and mixing it with water, and finally spraying it out together. When the fire truck is extinguishing a fire, the output flow rate and flow rate of water will also change according to different actual conditions. When the firefighting conditions of the fire truck change, this type of foam supply method is difficult to accurately control the output ratio of the foam. Summary of the invention

[0004] In view of the above-mentioned defects or shortcomings, the present invention provides a fire fighting system assembly and its foam ratio control method and fire fighting equipment, aiming to solve the technical problem that the existing fire fighting system of the fire truck cannot accurately control the output ratio of the foam.

[0005] To achieve the above object, the present invention provides a foam ratio control method for a fire fighting system assembly, wherein the foam ratio control method for a fire fighting system assembly comprises:

[0006] S100: obtaining the actual required flow rate of the foam;

[0007] S200: adjusting the rotation speed of the foam pump in the foam supply system so that the difference between the theoretical output flow rate of the foam pump and the actual required flow rate is a positive number and is less than a first preset value;

[0008] S300: adjusting the opening of the return pipe of the foam supply system until the absolute value of the difference between the actual output flow rate of the foam supply system and the actual required flow rate is less than a second preset value;

[0009] The reflux pipeline is used to guide the foam part output by the foam pump to the foam storage unit or the inlet of the foam pump.

[0010] In an embodiment of the present invention, S100: obtaining the actual required flow rate of foam specifically includes:

[0011] S110: Obtain the current water flow rate of the water pump in the fire water supply system;

[0012] S120: Calculate the actual required flow rate of the foam according to the current water output flow rate of the water pump and the desired mixing ratio of the foam and water.

[0013] In an embodiment of the present invention, S200: adjusting the rotation speed of the foam pump in the foam supply system so that the difference between the theoretical output flow rate of the foam pump and the actual required flow rate is a positive number and is less than a first preset value specifically includes:

[0014] S210: Calculating the required rotation speed of the foam pump corresponding to the actual required flow rate;

[0015] S220: increasing or decreasing the operating speed of the foam pump according to the positive or negative value of the difference between the current operating speed of the foam pump and the required speed;

[0016] S230: When the difference between the current operating speed of the foam pump and the required speed is a positive number and is smaller than a preset speed difference, stop adjusting the operating speed of the foam pump.

[0017] In an embodiment of the present invention, the operating speed of the foam pump is positively correlated with the magnitude of the control current of the foam pump. S220: increasing or decreasing the operating speed of the foam pump according to the positive or negative difference between the current operating speed of the foam pump and the required speed specifically includes:

[0018] When the difference between the current operating speed of the foam pump and the required speed is positive, and the difference between the current operating speed of the foam pump and the required speed is greater than a preset speed difference, periodically reducing the control current of the foam pump;

[0019] When the difference between the current operating speed of the foam pump and the required speed is negative, the control current of the foam pump is periodically increased.

[0020] In an embodiment of the present invention, the foam pump is a hydraulically driven pump, a proportional valve is provided on the driving oil circuit of the hydraulically driven pump, and the operating speed of the foam pump is adjusted by periodically increasing or decreasing the opening of the proportional valve;

[0021] When the required speed is less than the maximum rated speed of the foam pump, the calculation formula for the expected adjustment speed of the foam pump in each speed adjustment cycle is:

[0022] N d =K w *L w +K p *P w +K b *Q n *t b ;

[0023] Among them, N d Adjust the speed of the foam pump to the expected speed; L w is the actual flow rate at the pump outlet; K w is the conversion coefficient between the water pump outlet flow and the foam pump speed, which can be measured through experimental data; P w is the outlet pressure of the water pump; Kp is the conversion coefficient between the water pump outlet pressure and the foam pump speed, which is measured through experimental data; Q n is the current opening of the proportional valve; K b is the conversion coefficient between the opening of the proportional valve and the speed of the foam pump; t b It is the gear pump speed increase / decrease adjustment parameter corresponding to the current opening of the proportional valve.

[0024] In an embodiment of the present invention, when the required speed is greater than or equal to the maximum rated speed of the foam pump, N d =N max ; N max It is the maximum rated speed of the foam pump.

[0025] In an embodiment of the present invention, S300: adjusting the opening of the return pipe of the foam supply system until the absolute value of the difference between the actual output flow and the actual required flow of the foam supply system is less than the second preset value specifically includes:

[0026] S310: Obtaining the actual output flow rate of foam supplied from the foam supply system to the fire water supply system;

[0027] S320: increasing or decreasing the opening of the return line according to the positive or negative difference between the actual output flow rate of the foam supply system and the actual required flow rate;

[0028] S330: When the absolute value of the difference between the actual output flow rate of the foam supply system and the actual required flow rate is smaller than a second preset value, stop adjusting the opening of the return pipeline.

[0029] In an embodiment of the present invention, S320: increasing or decreasing the opening of the return line according to the positive or negative difference between the actual output flow rate of the foam supply system and the actual required flow rate specifically includes:

[0030] When the difference between the actual output flow rate and the actual required flow rate of the foam supply system is positive and the absolute value of the difference is greater than a second preset value, periodically increasing the control current of the foam pump;

[0031] When the difference between the actual output flow rate and the actual required flow rate of the foam supply system is negative and the absolute value of the difference is greater than a second preset value, the control current of the foam pump is periodically reduced.

[0032] In an embodiment of the present invention, the calculation formula for adjusting the opening of the return line is:

[0033] M d(t) =M d(t-1) +k(L d -L0)*t(L d -L0>S);

[0034] M d(t) =Md(t-1) -k(L d -L0)*t(L d -L0<-S);

[0035] M d(t) M is the opening of the return pipe after adjustment in the current adjustment cycle; d(t-1) The opening of the return pipe before the current regulation cycle; L d is the current foam mixed liquid ratio (the product of this parameter and k is the actual output flow of the foam supply system); L0 is the desired mixing ratio of foam and water (the product of this parameter and k is the actual required flow); k is the conversion coefficient of the deviation value of the current mixed liquid and the desired mixed liquid ratio to the opening adjustment; t is the opening adjustment value of the adjustment cycle.

[0036] To achieve the above-mentioned objectives, the present invention also provides a fire-fighting system assembly, which includes a foam supply system, a fire-fighting water supply system and a controller. The fire-fighting water supply system includes a water pump and a fire-fighting water output pipeline connected to the outlet of the water pump; the foam supply system includes a foam pump, a foam output pipeline and a return pipeline, one end of the foam output pipeline is connected to the outlet of the foam pump, and the other end is connected to the fire-fighting water output pipeline, one end of the return pipeline is connected to the foam output pipeline, and the other end is connected to the inlet of the foam storage unit or the foam pump, a proportional control valve for adjusting the opening is provided on the return pipeline, the controller is controlled and connected to the foam pump and the proportional control valve, and the controller is used to execute the method described above.

[0037] To achieve the above object, the present invention further provides a fire fighting device, wherein the fire fighting device comprises the fire fighting system assembly described above.

[0038] Through the above technical solution, the foam ratio control method of the fire protection system assembly provided by the embodiment of the present invention has the following beneficial effects:

[0039] This method analyzes the actual required flow rate of the foam, and first changes the rotation speed of the foam pump to achieve coarse adjustment of the foam pump output flow rate, and then changes the opening of the return line to achieve fine adjustment of the foam pump output flow rate within a small range. Through the coordination of coarse adjustment and fine adjustment, the foam output can be accurately adjusted to the appropriate proportion in a shorter time.

[0040] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are used to provide an understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention, but do not constitute a limitation of the present invention. In the accompanying drawings:

[0042] Figure 1is a general flow chart of a foam ratio control method of a fire protection system assembly according to an embodiment of the present invention;

[0043] Figure 2 is a specific flow chart of step S100 of the foam ratio control method of the fire fighting system assembly according to an embodiment of the present invention;

[0044] Figure 3 is a specific flow chart of step S200 of the foam ratio control method of the fire protection system assembly according to an embodiment of the present invention;

[0045] Figure 4 is a specific flow chart of step S300 of the foam ratio control method of the fire fighting system assembly according to an embodiment of the present invention;

[0046] Figure 5 Schematic diagram of the connection of the fire protection system assembly according to an embodiment of the present invention.

[0047] Description of Reference Numerals

[0048] 1. Foam supply system; 11. Foam pump; 12. Return pipeline; 121. Flow regulating valve; 13. Foam output pipeline; 14. Foam storage unit; 2. Fire water supply system; 21. Water pump; 22. Fire water output pipeline. DETAILED DESCRIPTION

[0049] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0050] The foam ratio control method of the fire fighting system assembly of the present invention will be described below with reference to the accompanying drawings.

[0051] The fire fighting system assembly of the present invention comprises a foam supply system 1 and a fire fighting water supply system 2. When the fire fighting system assembly is in operation, the foam supply system 1 outputs foam to the fire fighting water supply foam in the fire fighting water supply system 2. After the water and foam are mixed, they are sprayed out from the nozzle to extinguish the fire.

[0052] When facing different fire conditions, the flow rate of water sprayed by the fire water supply system 2 may be different, or the expected mixing ratio of foam and water may be different, resulting in different actual required flow rates of foam.

[0053] like Figure 1 and Figure 5 As shown, in order to ensure the mixing ratio of foam and water, the present invention provides a foam ratio control method of a fire fighting system assembly, wherein the foam ratio control method of the fire fighting system assembly includes:

[0054] S100: obtaining the actual required flow rate of the foam;

[0055] S200: adjusting the rotation speed of the foam pump 11 in the foam supply system 1 so that the difference between the theoretical output flow rate of the foam pump 11 and the actual required flow rate is a positive number and is less than a first preset value;

[0056] S300: adjusting the opening of the return pipe 12 of the foam supply system 1 until the absolute value of the difference between the actual output flow rate of the foam supply system 1 and the actual required flow rate is less than a second preset value;

[0057] The reflux line 12 is used to guide the foam portion output by the foam pump 11 to the foam storage unit 14 or the inlet of the foam pump 11, and the second preset value is smaller than the first preset value.

[0058] After analyzing the actual required flow rate of the foam, it is necessary to adjust the foam output flow rate of the foam pump 11 to the fire water supply system 2. The change in the rotation speed of the foam pump 11 will greatly change the output flow rate of the foam pump 11. By adjusting the rotation speed to change the output flow rate of the foam pump 11, the output flow rate of the foam pump 11 can be quickly adjusted to be close to the actual required flow rate. However, this method has low adjustment accuracy and can only roughly adjust the output flow rate of the foam pump 11 to be close to the actual required flow rate. For example, if the actual required flow rate of the foam is 80L / min, by adjusting the rotation speed of the foam pump 11, its output flow rate can only be guaranteed to be within the range of (80±80*3%)L / min.

[0059] After adjusting the theoretical output flow rate of the foam pump 11 to be slightly larger than the actual required flow rate, in order to further adjust the foam output flow rate of the foam pump 11, the method uses the return pipe 12 to return the excess foam output by the foam pump 11. Among them, the maximum flow rate that the return pipe 12 can return is much smaller than the output flow rate of the foam pump 11. For example, the maximum return flow rate of the return pipe 12 can be 10% or less of the current output flow rate of the foam pump 11. By changing the opening of the return pipe 12, the return flow rate of the return pipe 12 can be changed, thereby realizing the precise adjustment of the foam flow rate of the foam pump 11 to the fire water supply system 2 within a small range.

[0060] In summary, this method analyzes the actual required flow rate of the foam, and first changes the rotation speed of the foam pump 11 to achieve coarse adjustment of the output flow rate of the foam pump 11, and then changes the opening of the return pipe 12 to achieve fine adjustment of the output flow rate of the foam pump 11 within a small range. Through the coordination of coarse adjustment and fine adjustment, the foam output can be accurately adjusted to the appropriate proportion in a shorter time.

[0061] It is understandable that, in this method, when the rotation speed of the foam pump 11 is adjusted to the desired level, the theoretical output flow rate corresponding to the rotation speed of the foam pump 11 needs to be slightly greater than the actual required flow rate.

[0062] like Figure 2 and Figure 5 As shown, in the embodiment of the present invention, S100: obtaining the actual required flow rate of foam specifically includes:

[0063] S110: Obtain the current water flow rate of the water pump 21 in the fire water supply system 2;

[0064] S120: Calculate the actual required flow rate of the foam according to the current water output flow rate of the water pump 21 and the desired mixing ratio of the foam and water.

[0065] The current water flow rate of the water pump 21 will be different for different fire conditions. Therefore, when analyzing the actual required flow rate of the foam, it is necessary to first obtain the current water flow rate of the water pump 21 in the fire water supply system 2, and also to know the desired mixing ratio of foam and water. The desired mixing ratio of foam and water can be set manually, such as the firefighter inputting the desired mixing ratio of foam and water as 5% on the central control display screen of the fire equipment. After knowing the current water flow rate of the water pump 21 and the desired mixing ratio of foam and water, the actual required flow rate of the foam can be calculated by multiplying the two.

[0066] like Figure 3 and Figure 5 As shown, in an embodiment of the present invention, S200: adjusting the rotation speed of the foam pump 11 in the foam supply system 1 so that the difference between the theoretical output flow rate of the foam pump 11 and the actual required flow rate is a positive number and less than the first preset value specifically includes:

[0067] S210: Calculating the required rotation speed of the foam pump 11 corresponding to the actual required flow rate;

[0068] S220: increasing or decreasing the operating speed of the foam pump 11 according to the positive or negative value of the difference between the current operating speed of the foam pump 11 and the required speed;

[0069] S230 : When the difference between the current operating speed of the foam pump 11 and the required speed is a positive number and is smaller than a preset speed difference, the operating speed of the foam pump 11 is stopped from being adjusted.

[0070] There is a corresponding relationship between the theoretical output flow of the foam pump 11 and the rotation speed of the foam pump 11, and the corresponding relationship can be obtained through laboratory testing. After analyzing the actual required flow of the foam, find the rotation speed of the foam pump 11 corresponding to the flow, and use the rotation speed as the required rotation speed. After calculating the required rotation speed of the foam pump 11, increase the rotation speed of the foam pump 11 according to the positive or negative difference between the current operating rotation speed of the foam pump 11 and the required rotation speed, until the difference between the current operating rotation speed of the foam pump 11 and the required rotation speed is positive and less than the preset rotation speed difference, which means that the output flow of the foam pump 11 is roughly adjusted.

[0071] The purpose of adjusting the rotation speed of the foam pump 11 to be greater than the required rotation speed is to ensure that the theoretical output flow rate corresponding to the rotation speed of the foam pump 11 is greater than the actual required flow rate when the rotation speed adjustment of the foam pump 11 is completed.

[0072] In the embodiment of the present invention, for fire fighting equipment with its own hydraulic system, the foam pump 11 is preferably a hydraulically driven pump such as a hydraulic gear pump, which has the advantages of large pump power and small size, and can directly use the hydraulic system on the fire fighting equipment, which is convenient for power extraction. Of course, the foam pump 11 can also be a motor-driven pump. For the motor-driven pump, a separate power supply needs to be provided on the fire fighting equipment, and the motor needs to be waterproofed when the motor is installed.

[0073] In the embodiment of the present invention, the foam pump 11 can also directly draw power from the engine. However, this type of driving method makes it difficult to adjust the speed of the foam pump 11.

[0074] Take the foam pump 11 as an example of a hydraulically driven pump. A proportional valve is provided on the driving oil circuit of the hydraulically driven pump, and the opening of the proportional valve is positively correlated with the rotation speed of the foam pump 11. The operating speed of the foam pump 11 is adjusted by periodically increasing or decreasing the rotation speed of the foam pump 11;

[0075] When the required speed is less than the maximum rated speed of the foam pump 11, the calculation formula of the expected adjustment speed of the foam pump 11 in each speed adjustment cycle is:

[0076] N d =K w *L w +K p *P w +K b *Q n *t b ;

[0077] N d L is the expected adjustment speed of the foam pump 11; w is the actual flow rate at the outlet of the water pump 21; K w is the conversion coefficient between the outlet flow of the water pump 21 and the rotation speed of the foam pump 11, which can be measured through experimental data; w K is the outlet pressure of the water pump 21; p is the conversion coefficient between the outlet pressure of the water pump 21 and the rotation speed of the foam pump 11, which is measured through experimental data; Q n is the current opening of the proportional valve; K b is the conversion coefficient between the opening of the proportional valve and the speed of the foam pump 11; t b It is the gear pump speed increase / decrease adjustment parameter corresponding to the current opening of the proportional valve.

[0078] (K w *L w) represents the speed required by the foam pump 11 to press the foam into the fire water at the outlet of the water pump 21 with the current flow rate, (K p *P w ) represents the speed required by the foam pump 11 to press the foam into the fire water at the outlet of the water pump 21 at the current pressure, (K b *Q n ) represents the theoretical speed corresponding to the current opening of the proportional valve, (K b *Q n *t b ) represents the speed increase or decrease in this speed adjustment cycle. The greater the difference between the theoretical speed corresponding to the current opening of the proportional valve and the required speed, the greater the speed increase or decrease in this speed adjustment cycle. The speed increase or decrease in each speed adjustment cycle is determined by the parameter t b Adjust, that is, t b According to the difference between the theoretical speed and the required speed, the speed is always in a changing state. This adjustment method can adjust the speed of the foam pump to be close to the required speed more quickly.

[0079] It should be noted that periodically increasing or decreasing the speed of the foam pump 11 means calculating the expected adjustment speed once according to the above formula every preset time interval (such as every 100ms), and then roughly adjusting the speed of the foam pump 11 to be close to the expected adjustment speed, and repeating it multiple times until the difference between the current operating speed of the foam pump 11 and the required speed is a positive number and less than the preset speed difference. By periodically increasing or decreasing the foam pump 11, a closed-loop control of the speed of the foam pump 11 can be formed to avoid hysteresis or delay in the control of the foam pump 11.

[0080] In the embodiment of the present invention, when the required speed is greater than or equal to the maximum rated speed of the foam pump 11, N d =N max ; N max is the maximum rated speed of the foam pump 11.

[0081] In the embodiment of the present invention, for a hydraulically driven pump or a motor driven pump, its operating speed can be achieved by changing the magnitude of the control current of the foam pump 11 or the proportional valve in the driving oil circuit.

[0082] In an embodiment of the present invention, S220: increasing or decreasing the operating speed of the foam pump 11 according to the positive or negative value of the difference between the current operating speed of the foam pump 11 and the required speed specifically includes:

[0083] When the difference between the current operating speed of the foam pump 11 and the required speed is positive, and the difference between the current operating speed of the foam pump 11 and the required speed is greater than the preset speed difference, the control current of the foam pump 11 is periodically reduced;

[0084] When the difference between the current operating speed of the foam pump 11 and the required speed is negative, the control current of the foam pump 11 is periodically increased.

[0085] Periodically reducing or increasing the control current of the foam pump 11 means that the value of the control current increases by d at every preset time interval (such as 100ms). The control formula can be expressed by A=A0±kt. The value of d increased by the control current each time can be the same or different. The result after each adjustment is used as the input for comparison with the required speed, so that the speed of the gear pump can be accurately adjusted to a speed close to the required speed.

[0086] It is understandable that the foam ratio control method of the present invention can be dynamically adjusted according to the change of the current water outlet flow of the water pump 21. During firefighting operations, firefighters sometimes adjust the current water outlet flow of the water pump 21 according to the on-site situation. When the current water outlet flow of the water pump 21 changes, the system will recalculate the actual required flow of the foam and the required speed of the foam pump 11. If the flow of foam and water has reached a balance, the firefighter changes the water outlet flow of the water pump, and the output flow of the foam needs to be readjusted. When the difference between the current operating speed of the foam pump 11 and the required speed is greater than the preset speed difference, it means that the current foam output flow of the foam pump 11 is too much, and the mixing ratio of the foam water is greatly different from the expectation. At this time, the control current of the foam pump 11 can be periodically reduced to quickly reduce the speed and output flow of the foam pump 11, and then adjust the opening of the return pipe 12 for fine-tuning.

[0087] like Figure 4 and Figure 5 As shown, in an embodiment of the present invention, S300: adjusting the opening of the return pipe 12 of the foam supply system 1 until the absolute value of the difference between the actual output flow and the actual required flow of the foam supply system 1 is less than the second preset value specifically includes:

[0088] S310: Obtaining the actual output flow rate of foam from the foam supply system 1 to the fire water supply system 2;

[0089] S320: increasing or decreasing the opening of the return pipe 12 according to the positive or negative difference between the actual output flow rate of the foam supply system 1 and the actual required flow rate;

[0090] S330: When the absolute value of the difference between the actual output flow rate of the foam supply system 1 and the actual required flow rate is smaller than a second preset value, the adjustment of the opening degree of the return pipe 12 is stopped.

[0091] When the theoretical output flow rate of the foam pump 11 is adjusted to be greater than the actual required flow rate, the return pipe 12 may be in a conducting state, resulting in the actual output flow rate of the foam delivered by the foam pump 11 to the fire water supply system 2 being less than or greater than the actual required flow rate. At this time, the opening of the return pipe 12 needs to be increased or decreased accordingly according to the positive or negative difference between the actual output flow rate of the foam supply system 1 and the actual required flow rate. By constraining the absolute value of the difference between the actual output flow rate of the foam supply system 1 and the actual required flow rate within the second preset value, it can be ensured that the actual mixing ratio of the foam-water mixture is within the tolerance threshold of the desired mixing ratio of foam and water.

[0092] In the embodiment of the present invention, S320: increasing or decreasing the opening of the return line 12 according to the positive or negative difference between the actual output flow rate and the actual required flow rate of the foam supply system 1 specifically includes:

[0093] When the difference between the actual output flow rate of the foam supply system 1 and the actual required flow rate is positive and the absolute value of the difference is greater than a second preset value, the control current of the foam pump 11 is periodically increased;

[0094] When the difference between the actual output flow rate of the foam supply system 1 and the actual required flow rate is negative and the absolute value of the difference is greater than the second preset value, the control current of the foam pump 11 is periodically reduced.

[0095] Specifically, in the embodiment of the present invention, the calculation formula for adjusting the opening of the return line 12 is:

[0096] M d(t) =M d(t-1) +k(L d -L0)*t(L d -L0>S);

[0097] M d(t) =M d(t-1) -k(L d -L0)*t(L d -L0<-S);

[0098] M d(t) M is the opening of the return pipe 12 after adjustment in the current adjustment cycle; d(t-1) The opening of the front return pipe 12 is adjusted for the current adjustment cycle; L d is the current foam mixed liquid ratio (the product of this parameter and k is the actual output flow of the foam supply system 1); L0 is the desired mixing ratio of foam and water (the product of this parameter and k is the actual required flow); k is the conversion coefficient of the deviation value of the current mixed liquid and the desired mixed liquid ratio to the opening adjustment; t is the opening adjustment value of the adjustment cycle; S is the tolerance threshold.

[0099] If the current foam-water mixing ratio is greater than the desired foam-water mixing ratio (L d -L0>S), it means that the flow rate of foam delivered by the foam pump 11 to the fire water supply system 2 exceeds the limit, and the opening of the return pipe 12 needs to be increased to reduce the flow rate of foam delivered by the foam pump 11 to the fire water supply system 2. When increasing the opening of the return pipe 12, the opening of the return pipe 12 can be periodically increased (e.g., the opening is increased by t every 100ms) just like the speed regulation of the foam pump 11. By periodically increasing or decreasing the control current of the foam pump 11, feedback regulation and closed-loop control of the opening of the return pipe 12 can be achieved. Similarly, if the current foam-water mixing ratio is greater than the desired foam-water mixing ratio (L d -L0<-S), the opening of the return line 12 is periodically reduced.

[0100] In the embodiment of the present invention, before the foam pump 11 is started, it is also necessary to judge the starting conditions to ensure the safe operation of the equipment. The starting conditions may be whether the fire-fighting equipment is in a folded state or a working state, whether the water pump 21 has been started, whether the foam liquid in the foam tank is sufficient, etc. The starting conditions can be adjusted according to the structural characteristics of the fire-fighting equipment itself.

[0101] like Figure 5 As shown, in order to achieve the above-mentioned purpose, the present invention also provides a fire protection system assembly, which includes a foam supply system 1, a fire water supply system 2 and a controller. The fire water supply system 2 includes a water pump 21 and a fire water output pipeline 22 connected to the outlet of the water pump 21; the foam supply system 1 includes a foam pump 11, a foam output pipeline 13 and a return pipeline 12, one end of the foam output pipeline 13 is connected to the outlet of the foam pump 11, and the other end is connected to the fire water output pipeline 22, one end of the return pipeline 12 is connected to the foam output pipeline 13, and the other end is connected to the foam storage unit 14 or the inlet of the foam pump 11, and a proportional control valve for adjusting the opening is provided on the return pipeline 12, and the controller is connected to the foam pump 11 and the proportional control valve. The controller is used to execute the method described above, and the controller is also used for data collection, calculation and control of each valve.

[0102] like Figure 5 As shown, in the embodiment of the present invention, by connecting the foam output pipeline 13 to the fire water output pipeline 22, it is possible to prevent the foam from passing through the water pump 21 and causing corrosion to the water pump 21, thereby increasing the service life of the water pump 21. At the same time, the foam pump 11 is used to independently supply foam, which can prevent the outlet pressure of the water pump 21 from decreasing, thereby achieving the purpose of increasing the spraying distance of the fire water.

[0103] like Figure 5As shown, in an embodiment of the present invention, the foam supply system 1 further comprises a pressure relief valve connected in parallel with the pipeline of the foam pump 11, and the pressure relief valve is used for safely releasing pressure when the outlet pressure of the foam pump 11 is too high.

[0104] like Figure 5 As shown, in an embodiment of the present invention, a foam flow meter and a foam pressure gauge are also provided on the foam output pipeline 13, and the foam flow meter and the foam pressure gauge are used to detect the flow rate and pressure of the foam delivered by the foam pump 11 to the fire water supply system 2.

[0105] In the embodiment of the present invention, a water flow meter and a water pressure meter are provided on the fire water output pipeline 22 , and the water flow meter and the water pressure meter are used to detect the pressure and flow of water at the outlet of the water pump 21 .

[0106] To achieve the above object, the present invention further provides a fire-fighting device, wherein the fire-fighting device includes the fire-fighting system assembly described above. The fire-fighting device may be a fire truck. Since the fire-fighting device adopts all the technical solutions of the above embodiments, it at least has the beneficial effects brought by the above embodiments, which will not be repeated here.

[0107] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0108] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0109] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0110] Although the embodiments of the present invention have been described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A foam ratio control method for a fire fighting system assembly, characterized in that: The foam ratio control method of the fire protection system assembly includes: Get the actual demand flow of the bubble; Adjusting the rotation speed of a foam pump (11) in a foam supply system (1) so that the difference between a theoretical output flow rate of the foam pump (11) and the actual required flow rate is a positive number and is less than a first preset value; Adjusting the opening of the return pipe (12) of the foam supply system (1) until the absolute value of the difference between the actual output flow rate of the foam supply system (1) and the actual required flow rate is less than a second preset value; The reflux pipeline (12) is used to guide the foam portion output by the foam pump (11) to the foam storage unit (14) or the inlet of the foam pump (11).

2. The foam ratio control method of the fire fighting system assembly according to claim 1, characterized in that: The actual required flow to obtain foam specifically includes: Obtaining the current water flow rate of the water pump (21) in the fire water supply system (2); The actual required flow rate of the foam is calculated according to the current water output flow rate of the water pump (21) and the desired mixing ratio of foam and water.

3. The foam ratio control method of the fire fighting system assembly according to claim 2, characterized in that: Adjusting the rotation speed of a foam pump (11) in a foam supply system (1) so that the difference between a theoretical output flow rate of the foam pump (11) and an actual required flow rate is a positive number and is less than a first preset value specifically comprises: Calculating the required rotation speed of the foam pump (11) corresponding to the actual required flow rate; According to the positive or negative value of the difference between the current operating speed of the foam pump (11) and the required speed, the operating speed of the foam pump (11) is increased or decreased; When the difference between the current operating speed of the foam pump (11) and the required speed is a positive number and the difference is smaller than a preset speed difference, the operating speed of the foam pump (11) is stopped from being adjusted.

4. The foam ratio control method of the fire fighting system assembly according to claim 3, characterized in that: The foam pump (11) is a hydraulically driven pump, a proportional valve is provided on the driving oil circuit of the hydraulically driven pump, and the operating speed of the foam pump (11) is adjusted by periodically increasing or decreasing the operating speed of the foam pump (11); When the required rotational speed is less than the maximum rated rotational speed of the foam pump (11), the calculation formula for the expected adjustment rotational speed of the foam pump (11) in each rotational speed adjustment cycle is: N d =K w *L w +K p *P w +K b *B n *t b ; Among them, N d L is the expected adjustment speed of the foam pump (11); w is the actual flow rate at the outlet of the water pump (21); K w is the conversion coefficient between the outlet flow rate of the water pump (21) and the rotation speed of the foam pump (11), which can be measured through experimental data; P w K is the outlet pressure of the water pump (21); p is the conversion coefficient between the outlet pressure of the water pump (21) and the rotation speed of the foam pump (11), which is measured through experimental data; Q n is the current opening of the proportional valve; K b is the conversion coefficient between the opening of the proportional valve and the rotation speed of the foam pump (11); t b It is the gear pump speed increase / decrease adjustment parameter corresponding to the current opening of the proportional valve.

5. The foam ratio control method of the fire fighting system assembly according to claim 3, characterized in that: The operating speed of the foam pump (11) is positively correlated with the magnitude of the control current of the foam pump (11), and increasing or decreasing the operating speed of the foam pump (11) according to the positive or negative difference between the current operating speed of the foam pump (11) and the required speed specifically includes: When the difference between the current operating speed of the foam pump (11) and the required speed is positive, and the difference between the current operating speed of the foam pump (11) and the required speed is greater than the preset speed difference, periodically reducing the control current of the foam pump (11); When the difference between the current operating speed of the foam pump (11) and the required speed is negative, the control current of the foam pump (11) is periodically increased.

6. The foam ratio control method of a fire fighting system assembly according to any one of claims 1 to 5, characterized in that: Adjusting the opening of the return pipe (12) of the foam supply system (1) until the absolute value of the difference between the actual output flow of the foam supply system (1) and the actual required flow rate is less than a second preset value specifically comprises: Obtaining the actual output flow rate of the foam supplied by the foam supply system (1) to the fire water supply system (2); According to the positive or negative difference between the actual output flow rate of the foam supply system (1) and the actual required flow rate, the opening of the return pipe (12) is increased or decreased accordingly; When the absolute value of the difference between the actual output flow rate of the foam supply system (1) and the actual required flow rate is less than a second preset value, the adjustment of the opening of the return pipeline (12) is stopped.

7. The foam ratio control method of the fire fighting system assembly according to claim 6, characterized in that: According to the positive or negative difference between the actual output flow rate of the foam supply system (1) and the actual required flow rate, the opening degree of the return pipe (12) is increased or decreased accordingly, specifically including: When the difference between the actual output flow rate of the foam supply system (1) and the actual required flow rate is positive and the absolute value of the difference is greater than the second preset value, periodically increasing the control current of the foam pump (11); When the difference between the actual output flow rate of the foam supply system (1) and the actual required flow rate is negative and the absolute value of the difference is greater than the second preset value, the control current of the foam pump (11) is periodically reduced.

8. The foam ratio control method of the fire fighting system assembly according to claim 7, characterized in that: The calculation formula for adjusting the opening of the return line (12) is: M d(t) =M d(t-1) +k(L d -L0)*t(L d -L0>S); M d(t) =M d(t-1) -k(L d -L0)*t(L d -L0<-S); M d(t) M is the opening of the return pipe (12) after adjustment in the current adjustment cycle; d(t-1) The opening of the front return pipe (12) is adjusted during the current adjustment cycle; L d is the current foam mixed liquid ratio (the product of this parameter and k is the actual output flow of the foam supply system (1)); L0 is the desired mixing ratio of foam and water (the product of this parameter and k is the actual required flow rate); k is the conversion coefficient of the deviation value of the current mixed liquid and the desired mixed liquid ratio to the opening adjustment; t is the opening adjustment value of the adjustment cycle.

9. A fire protection system assembly, characterized in that: include: A fire water supply system (2), comprising a water pump (21) and a fire water output pipeline (22) connected to the outlet of the water pump (21); A foam supply system (1), comprising a foam pump (11), a foam output pipeline (13) and a return pipeline (12), wherein one end of the foam output pipeline (13) is connected to the outlet of the foam pump (11), and the other end is connected to the fire water output pipeline (22); one end of the return pipeline (12) is connected to the foam output pipeline (13), and the other end is communicated with the foam storage unit (14) or the inlet of the foam pump (11); and a proportional regulating valve for adjusting the opening is provided on the return pipeline (12); and A controller is control-connected to the foam pump (11) and the proportional regulating valve, and the controller is used to execute the method according to any one of claims 1 to 8.

10. A fire fighting equipment, characterized in that: The fire fighting equipment comprises the fire fighting system assembly according to claim 9.

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