Control method for automatic fire extinguishing device of heavy telescopic boom forklift

Abstract

The invention provides a control method for an automatic fire extinguishing device of a heavy telescopic boom forklift. The control method comprises the following steps that S1, a current dynamic threshold value range model and an oil pressure dynamic threshold value range model are established according to historical load weight data and corresponding historical current data and historical oil pressure data; s2, current load data and current data are obtained, and if the current data exceed the current dynamic threshold range model, the step S3 is carried out; and S3, judging whether a fire risk exists or not according to a flame sensor, and if yes, entering the step S4. By judging whether an oil leakage phenomenon exists or not, when an oil fire disaster is caused by electric leakage, the fire behavior spreads quickly and even the explosion risk exists easily, and at the moment, an automatic fire extinguishing device needs to be controlled to output a large-dose fire extinguishing agent which is sprayed in all directions; and when oil leakage does not exist, the fire behavior spreading trend caused by the electrical fire disaster is small, at the moment, accurate fire extinguishing is conducted through a small-dose fire extinguishing agent, and the situation that the fire extinguishing agent is excessively used can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of automatic fire extinguishing, and in particular to a control method for an automatic fire extinguishing device of a heavy telescopic arm forklift. Background Art

[0002] With the rapid development of logistics and industry, heavy-duty telescopic forklifts are widely used in cargo handling and stacking. Its complex structure includes a hydraulic pump, a hydraulic oil pipeline connected to the hydraulic pump, a fuel tank, a diesel or gasoline pipeline connected to the fuel tank, a battery, and various circuits and electronic components connected to the battery. Usually, the hydraulic pump, fuel tank, battery, etc. are installed in the main control box of the forklift.

[0003] Since the components in the main control box are closely spaced, when a single component catches fire, it is easy to spread to other components, threatening the driver's safety and the integrity of the forklift structure. When the existing automatic fire extinguishing device is applied to the main control box for fire extinguishing, in the early stage of the fire, it is difficult to accurately control the amount of fire extinguishing agent, which can easily lead to excessive use of fire extinguishing agent, causing unnecessary damage to the forklift parts that have not been ignited, increasing the difficulty of subsequent cleaning and maintenance costs, and damaging the remaining normal electronic components. Summary of the invention

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to propose a control method for an automatic fire extinguishing device of a heavy telescopic forklift to solve the problems mentioned in the above background technology section.

[0005] The present invention is achieved through the following technical solutions: A control method for an automatic fire extinguishing device of a heavy telescopic forklift comprises the following steps: S1. Establishing a current dynamic threshold range model and an oil pressure dynamic threshold range model respectively according to historical load weight data and corresponding historical current data and historical oil pressure data; S2, obtaining current load data and current current data, if the current current data exceeds the current dynamic threshold range model, proceed to step S3; S3, judging whether there is a fire risk according to the flame sensor, if yes, proceeding to step S4; S4. Obtain current oil pressure data. If the current oil pressure data exceeds the oil pressure dynamic threshold range model, it is determined that the oil fire is caused by leakage and the first-level fire extinguishing is performed. Otherwise, it is determined that it is an electrical fire and the second-level fire extinguishing is performed. The first-level fire extinguishing is to control the automatic fire extinguishing device to output a large dose of fire extinguishing agent that is sprayed in all directions, and the second-level fire extinguishing is to control the automatic fire extinguishing device to output a small dose of fire extinguishing agent that is sprayed accurately.

[0006] Furthermore, the heavy-duty telescopic forklift includes: a frame, a lifting arm rotatably arranged on the frame, and a driver's cabin arranged on the frame, the frame including a main control box, and the main control box is evenly arranged with multiple flame sensors and corresponding injection ports of the automatic fire extinguishing device controlled by them.

[0007] Furthermore, in step S3, the step of determining whether there is a fire risk according to the flame sensor includes: S31, calculating the first-order difference value of the temperature of the flame sensor in the set interval time period according to the time series, obtaining the temperature change rate, and then performing a secondary difference calculation on the first-order difference value to obtain the acceleration value of the temperature change; S32. Based on the calculation results of the temperature change rate and the acceleration value, if the temperature change rate continues to be positive and the acceleration value is greater than the set threshold, it is determined that there is a fire risk.

[0008] Furthermore, in step S4, controlling the automatic fire extinguishing device to output a small dose of fire extinguishing agent that is precisely sprayed specifically includes: S41, obtaining temperature distribution data of the flame sensor, and extracting heat source points for data whose temperature exceeds the open flame temperature value; S42, calculating the coordinate value of the flame center through the heat source point; S43. Calculate the fire area according to the coordinate value of the heat source point and the coordinate value of the flame center, and adjust the amount of fire extinguishing agent according to the fire area.

[0009] Furthermore, in step S43, the amount of the fire extinguishing agent is calculated by the following formula:

[0010] In the formula, Indicates the amount of fire extinguishing agent used. represents the fire extinguishing efficiency coefficient, Represents the total number of heat source points, Indicates The temperature value of the heat source point, Represents the coordinate values ​​of each heat source point, Indicates the coordinate value of the flame center.

[0011] Furthermore, the step S3 further includes the following steps: S33: If the current data exceeds the dynamic threshold range and the flame sensor determines that there is a risk of fire, the electrical system of the forklift is cut off.

[0012] Furthermore, the step S4 further includes the following steps: S44: If the current oil pressure data exceeds the dynamic threshold range, all oil circuits of the forklift are cut off from outputting oil.

[0013] Furthermore, the method further comprises step S5: S5. When the flame sensor reaches the flame triggering threshold, the process proceeds to step S4.

[0014] Furthermore, the method further comprises step S6: S6. When the flame sensor detects that the temperature is lower than the fire extinguishing stop threshold, the fire extinguishing operation is stopped.

[0015] The beneficial effects of the present invention are as follows: judging whether there is leakage through the relationship between the current current data and the current dynamic threshold range model, because leakage is one of the important causes of fire inside the forklift, and then judging whether there is a fire risk through the flame sensor, and then judging whether there is oil leakage. When leakage causes oil fire, it is easy to cause the fire to spread rapidly and even there is a risk of explosion. At this time, it is necessary to control the automatic fire extinguishing device to output a large dose of fire extinguishing agent for all-round spraying; when there is no oil leakage, the fire spread tendency caused by the electrical fire is relatively small. At this time, precise fire extinguishing is carried out through a smaller dose of fire extinguishing agent, which can avoid excessive use of fire extinguishing agent, resulting in unnecessary damage to forklift parts in the non-fired area, and at the same time reduce the difficulty of later cleaning and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Flow chart of the control method of the present invention.

[0017] Figure 2 It is a three-dimensional diagram of a forklift of the present invention.

[0018] The above drawings include the following reference numerals: 1. Frame; 11. Main control box; 2. Lifting arm. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0020] A control method for an automatic fire extinguishing device of a heavy telescopic forklift comprises the following steps: S1. Establishing a current dynamic threshold range model and an oil pressure dynamic threshold range model respectively according to historical load weight data and corresponding historical current data and historical oil pressure data; S2, obtaining current load data and current current data, if the current current data exceeds the current dynamic threshold range model, proceed to step S3; S3, judging whether there is a fire risk according to the flame sensor, if yes, proceeding to step S4; S4. Obtain current oil pressure data. If the current oil pressure data exceeds the oil pressure dynamic threshold range model, it is determined that the oil fire is caused by leakage and the first-level fire extinguishing is performed. Otherwise, it is determined that it is an electrical fire and the second-level fire extinguishing is performed. The first-level fire extinguishing is to control the automatic fire extinguishing device to output a large dose of fire extinguishing agent that is sprayed in all directions, and the second-level fire extinguishing is to control the automatic fire extinguishing device to output a small dose of fire extinguishing agent that is sprayed accurately.

[0021] Specifically, in step S1, assuming that the historical load data is 500 kg, the historical current value at the corresponding historical time point is 10 amperes, and the current fluctuation range is set to ±2 amperes, that is, when the load is 500 kg, the current dynamic threshold range is 8 amperes to 12 amperes. When the load weight is 100 kg, the current value at the corresponding historical time point is 7 amperes, that is, when the load is 100 kg, the current dynamic threshold range is 5 amperes to 9 amperes. Therefore, according to the relationship between the historical load data and the historical current value, the current dynamic threshold range model is constructed.

[0022] Similarly, the oil pressure dynamic threshold range model can be constructed through historical load weight data and corresponding historical oil pressure data.

[0023] In step S2, the current load weight information and current current data are obtained. If the current current data exceeds the current dynamic threshold range, it indicates that a short circuit may occur. Short circuit is one of the main causes of fire inside the main control box 11 of the forklift. Therefore, when the current data is abnormal, enter step S3.

[0024] In step S3, the step of determining whether there is a fire risk according to the flame sensor includes: S31, calculating the first-order difference value of the temperature of the flame sensor in the set interval time period according to the time series, obtaining the temperature change rate, and then performing a secondary difference calculation on the first-order difference value to obtain the acceleration value of the temperature change; S32. Based on the calculation results of the temperature change rate and the acceleration value, if the temperature change rate continues to be positive and the acceleration value is greater than the set threshold, it is determined that there is a fire risk.

[0025] Assuming that the temperature data at every half-second interval is [30℃, 35℃, 42℃, 52℃, 65℃], the temperature difference between adjacent time points is calculated by using the first-order difference method. The first-order difference refers to the difference between two adjacent temperature data. The calculation formula is: ΔTi=Ti+1-Ti, then, ΔT1=35-30=5, ΔT2=42-35=7, ΔT3=52-42=10, ΔT4=65-52=13. At the same time, the system uses the second-order difference method to further analyze the acceleration of temperature change. The calculation formula for the second-order difference is: Δ 2 Ti=ΔTi+1-ΔTi, then, Δ 2 T1=ΔT2-ΔT1=7-5=2, Δ 2 T2=ΔT3-ΔT2=10-7=3,Δ 2 T3=ΔT4-ΔT3=13-10=3.

[0026] In step S32, assuming that the set threshold value of acceleration is 1.5, the temperature change rate in the above example is continuously positive and the acceleration value is greater than the set threshold value. Therefore, it is indicated that the temperature inside the main control box 11 is abnormally increased, and the risk of spontaneous combustion is extremely high, and even an open flame exists. Then, step S4 is used to determine whether there is an oil leakage phenomenon.

[0027] In the initial stage after the forklift is started, it is normal for the temperature to rise. At this time, if the temperature change rate continues to be positive and the acceleration value is between 0 and the set threshold, it can be judged as a normal heating process. Therefore, the set threshold of the acceleration is set to be greater than zero and can be adjusted according to the experience value, which is not limited here.

[0028] In step S4, if the current oil pressure data exceeds the oil pressure dynamic threshold range model, it is determined that there is an oil leakage phenomenon. At this time, it is necessary to be alert to the risk of leakage sparks contacting the leaked oil, thereby causing the rapid spread of flames, and because the internal space of the main control box 11 is small, there is a risk of explosion caused by the spread of flames. Therefore, it is determined that the oil fire is caused by leakage and the first-level fire extinguishing is performed. The first-level fire extinguishing is to control the automatic fire extinguishing device to output a large dose of fire extinguishing agent in all directions.

[0029] In step S4, if the current oil pressure data does not exceed the oil pressure dynamic threshold range model, it is determined that there is no oil leakage. When there is no oil leakage, the fire caused by the electrical fire spreads slowly. At this time, a small dose of fire extinguishing agent is used to accurately extinguish the fire, which can avoid excessive use of fire extinguishing agent and unnecessary damage to forklift parts in the non-fired area, and reduce the difficulty of later cleaning and maintenance costs.

[0030] In step S4, controlling the automatic fire extinguishing device to output a small dose of fire extinguishing agent that is precisely sprayed specifically includes: S41, obtaining temperature distribution data of the flame sensor, and extracting heat source points for data whose temperature exceeds the open flame temperature value; S42, calculating the coordinate value of the flame center through the heat source point; S43. Calculate the fire area according to the coordinate value of the heat source point and the coordinate value of the flame center, and adjust the amount of fire extinguishing agent according to the fire area.

[0031] In step S43, the amount of fire extinguishing agent is calculated by the following formula:

[0032] In the formula, Indicates the amount of fire extinguishing agent used. represents the fire extinguishing efficiency coefficient, Represents the total number of heat source points, Indicates The temperature value of the heat source point, Represents the coordinate value of each heat source point, Indicates the coordinate value of the flame center.

[0033] Specifically, in S41, the open flame temperature value is set to 200°C, and the heat source point is extracted for the data whose temperature exceeds the open flame temperature value; Assume that 5 heat source points are detected ( =5), and draw the table as follows:

[0034] Calculate the flame center using the above table The coordinate value of That is, the horizontal coordinate of the flame center: , the vertical coordinate of the flame center: .

[0035] The coordinate difference between each heat source point and the flame center is calculated in turn, and the maximum radius of the flame is calculated accordingly. In the above example, the second group of heat source points is the maximum radius of the flame, that is, The value of is 0.256.

[0036] In the above example, the average temperature of each heat source point is calculated, that is, The value is 410℃.

[0037] In the above example, It represents the fire extinguishing efficiency coefficient, and its unit is L / (℃·m²·s). The fire extinguishing efficiency coefficient is related to the choice of fire extinguishing agent, such as carbon dioxide fire extinguishing agent, dry powder fire extinguishing agent, etc. Different fire extinguishing agents have different fire extinguishing efficiency coefficients. In this example, 0.05 can be taken.

[0038] Then, the calculated amount of extinguishing agent is It is 4.21L / s.

[0039] As an extended embodiment of step S3, it also includes step S31: if the current current data exceeds the dynamic threshold range and the flame sensor determines that there is a risk of fire, the electrical system of the forklift is cut off. By cutting off the electrical system of the forklift, continuous leakage leading to continuous generation of electric sparks is avoided, thereby avoiding the generation of new ignition points.

[0040] As an extended embodiment of step S4, step S44 is also included. If the current oil pressure data exceeds the dynamic threshold range, all oil circuits of the forklift are cut off from outputting oil. This step can prevent the oil from continuing to leak and causing the flame to spread further.

[0041] The present invention further comprises step S5. When the flame sensor reaches the flame triggering threshold, the process proceeds to step S4.

[0042] In step S5, the flame triggering threshold can be set to 200℃~300℃. When the temperature data exceeds this threshold, it can be determined that there is an open flame. The above parameters can be set based on actual application experience. The purpose is to detect the open flame in time and determine whether there is an oil leak through step S4 to avoid the open flame from contacting the leaked oil and then the flame spreads rapidly, or even causes the risk of explosion.

[0043] Both step S4 and step S5 can start the fire extinguishing work. Step S4 is mainly used to detect whether the temperature inside the main control box 11 rises abnormally due to leakage. Step S5 is mainly for other unknown reasons, which lead to the existence of open fire inside the main control box 11. Through step S4 and step S5, it can be ensured that the main control box 11 can be identified at the early stage of the fire to prevent the fire from spreading.

[0044] Reference Figure 2 As shown, the heavy-duty telescopic forklift includes: a frame 1, a lifting and lifting arm 2 rotatably arranged on the frame 1, and a driver's cabin arranged on the frame 1. The frame 1 includes a main control box 11, and the main control box 11 is evenly arranged with multiple flame sensors and corresponding injection ports of the automatic fire extinguishing device controlled by them, and an appropriate amount of fire extinguishing agent is sprayed through the injection ports.

[0045] In step S42, after the coordinate value of the flame center is determined, the automatic fire extinguishing device in the area is controlled accordingly, and the spray port is rotated so that the spray port sprays the fire extinguishing agent toward the coordinate value of the flame center.

[0046] Among them, during the first level of fire extinguishing, the automatic fire extinguishing device adjusts the output of the injection port to the maximum, so as to inject the fire extinguishing agent as quickly and as much as possible.

[0047] As an extended embodiment, during the secondary fire extinguishing, through the steps S41 to S43 of the present invention, the amount of fire extinguishing agent is dynamically adjusted, and the temperature distribution data of the flame sensor can be obtained multiple times during the fire extinguishing process, and the heat source point is extracted for the data whose temperature exceeds the open flame temperature value; thereby the amount of fire extinguishing agent is dynamically adjusted multiple times. By controlling the amount of fire extinguishing agent used in real time, it can further avoid excessive use of fire extinguishing agent and unnecessary damage to forklift parts in non-fire areas, while reducing the difficulty of subsequent cleaning and maintenance costs.

[0048] Through step S6, when the flame sensor detects that the temperature is lower than the fire extinguishing stop threshold, the fire extinguishing work is stopped, wherein the fire extinguishing stop threshold can be set to 20℃~40℃, and it can be judged that the open fire has been extinguished. The fire extinguishing stop threshold parameter can be set based on actual application experience, aiming to further avoid excessive use of fire extinguishing agent, avoid unnecessary damage to other parts of the forklift caused by the fire extinguishing agent, and reduce the workload of later maintenance and cleaning.

[0049] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0050] In the description of the present invention, 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 the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A control method for an automatic fire extinguishing device of a heavy telescopic forklift, characterized in that: The following steps are involved: S1. Establishing a current dynamic threshold range model and an oil pressure dynamic threshold range model respectively according to historical load weight data and corresponding historical current data and historical oil pressure data; S2, obtaining current load data and current current data, if the current current data exceeds the current dynamic threshold range model, proceed to step S3; S3, judging whether there is a fire risk according to the flame sensor, if yes, proceeding to step S4; S4. Obtain current oil pressure data. If the current oil pressure data exceeds the oil pressure dynamic threshold range model, it is determined that the oil fire is caused by leakage and the first-level fire extinguishing is performed. Otherwise, it is determined that it is an electrical fire and the second-level fire extinguishing is performed. The first-level fire extinguishing is to control the automatic fire extinguishing device to output a large dose of fire extinguishing agent that is sprayed in all directions, and the second-level fire extinguishing is to control the automatic fire extinguishing device to output a small dose of fire extinguishing agent that is sprayed accurately.

2. The control method of the automatic fire extinguishing device of a heavy telescopic forklift according to claim 1, characterized in that: The heavy-duty telescopic forklift comprises: a frame, a lifting arm rotatably arranged on the frame, and a driver's cabin arranged on the frame. The frame comprises a main control box, and the main control box is evenly arranged with a plurality of flame sensors and corresponding injection ports of an automatic fire extinguishing device controlled by the flame sensors.

3. The control method of the automatic fire extinguishing device of a heavy telescopic forklift according to claim 1, characterized in that: In step S3, the step of determining whether there is a fire risk according to the flame sensor includes: S31, calculating the first-order difference value of the temperature of the flame sensor in the set interval time period according to the time series, obtaining the temperature change rate, and then performing a secondary difference calculation on the first-order difference value to obtain the acceleration value of the temperature change; S32. Based on the calculation results of the temperature change rate and the acceleration value, if the temperature change rate continues to be positive and the acceleration value is greater than the set threshold, it is determined that there is a fire risk.

4. The control method of the automatic fire extinguishing device of a heavy telescopic forklift according to claim 1, characterized in that: In step S4, controlling the automatic fire extinguishing device to output a small dose of fire extinguishing agent that is precisely sprayed specifically includes: S41, obtaining temperature distribution data of the flame sensor, and extracting heat source points for data whose temperature exceeds the open flame temperature value; S42, calculating the coordinate value of the flame center through the heat source point; S43. Calculate the fire area according to the coordinate value of the heat source point and the coordinate value of the flame center, and adjust the amount of fire extinguishing agent according to the fire area.

5. The control method of the automatic fire extinguishing device of a heavy telescopic forklift according to claim 4, characterized in that: In step S43, the amount of the fire extinguishing agent is calculated by the following formula: In the formula, Indicates the amount of fire extinguishing agent used. represents the fire extinguishing efficiency coefficient, Represents the total number of heat source points, Indicates The temperature value of the heat source point, Represents the coordinate value of each heat source point, Indicates the coordinate value of the flame center.

6. The control method of the automatic fire extinguishing device of a heavy telescopic forklift according to claim 1, characterized in that: The step S3 also includes the following steps: S33: If the current data exceeds the dynamic threshold range and the flame sensor determines that there is a risk of fire, the electrical system of the forklift is cut off.

7. The control method of the automatic fire extinguishing device of a heavy telescopic forklift according to claim 1, characterized in that: The step S4 also includes the following steps: S44: If the current oil pressure data exceeds the dynamic threshold range, all oil circuits of the forklift are cut off from outputting oil.

8. The control method of the automatic fire extinguishing device of a heavy telescopic forklift according to claim 1, characterized in that: The step S5 is also included: S5. When the flame sensor reaches the flame triggering threshold, the process proceeds to step S4.

9. The control method of the automatic fire extinguishing device of a heavy telescopic forklift according to claim 1, characterized in that: The step S6 is also included: S6. When the flame sensor detects that the temperature is lower than the fire extinguishing stop threshold, the fire extinguishing operation is stopped.

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