Fire fighting truck air suspension suppression system and suppression method based on supporting leg state detection and fire fighting truck

Abstract

The invention discloses a fire fighting truck air suspension suppression system based on supporting leg state detection. A main controller of a fire fighting truck is connected and communicated with a chassis controller to cooperatively control an air suspension system; the main controller is connected with the landing leg in-place sensor, the oil pump power takeoff and the water pump power takeoff; the chassis controller is connected with a vehicle speed sensor, a gear sensor and a hand brake sensor. Meanwhile, the invention discloses a suppression method based on the suppression system. Whether the air suspension adjusting function of the vehicle needs to be restrained or not can be accurately and rapidly judged, energy waste caused by air inflation and deflation of an air suspension electromagnetic valve can be reduced, and damage to an air suspension system and the vehicle due to the fact that air inflation supply is not timely after the supporting legs are recycled can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of fire truck air suspension control, and in particular to a fire truck air suspension suppression system and suppression method based on outrigger state detection, and a fire truck. Background Art

[0002] The air suspension system is a new vehicle suspension technology that replaces traditional steel coil springs with air springs. It fills a sealed airbag with compressed air, leveraging the compressibility of the gas to achieve shock absorption and vehicle height adjustment. Compared to traditional suspension, air suspension significantly improves vehicle comfort and stability, effectively filtering out road bumps. It also automatically adjusts vehicle height based on load and road conditions, reducing wind resistance and optimizing vehicle maneuverability. Furthermore, the system features load-adaptive capability, enhancing support under heavy loads to ensure safe vehicle operation. It is widely used in high-end passenger cars, buses, and special engineering vehicles.

[0003] Large fire trucks with booms are typically equipped with telescopic booms tens of meters long, used for high-altitude firefighting and rescue operations. For fire trucks with outriggers, the outriggers often need to be raised completely off the ground before extending the boom to ensure balance and stability during boom operation and prevent tipping.

[0004] When outriggers are operating on large fire trucks, suppressing the air suspension system's automatic adjustment function is crucial. On the one hand, continuous automatic adjustment causes the air suspension solenoid valve to frequently inflate and deflate, resulting in unnecessary energy loss, increasing operating costs and potentially shortening the equipment's lifespan. On the other hand, if the air suspension continues to operate during outrigger operations, the system may be unable to restore support force in time when the outriggers retract due to delayed air supply, causing the vehicle to momentarily lose balance. This imbalance not only increases mechanical stress on the air suspension components but can also cause damage such as frame distortion and abnormal tire wear, seriously impacting vehicle performance and safety. Summary of the Invention

[0005] Purpose of the invention: The first purpose of the present invention is to propose an air suspension suppression system for fire trucks based on outrigger status detection; The second objective is to propose a method for suppressing the air suspension suppression system of a fire truck based on outrigger status detection. This method can accurately and quickly determine whether the vehicle requires suppression of the air suspension adjustment function. This not only reduces energy waste caused by the inflation and deflation of the air suspension solenoid valve, but also avoids damage to the air suspension system and vehicle caused by untimely inflation after outrigger retraction. The third object is to provide a fire truck comprising the above-mentioned fire truck air suspension suppression system based on outrigger status detection.

[0006] Technical solution: The present invention discloses a fire truck air suspension suppression system based on outrigger status detection. The main controller of the fire truck communicates with the chassis controller to coordinate and control the air suspension system. The main controller is connected to the outrigger position sensor, the oil pump power take-off and the water pump power take-off; The chassis controller is connected to a vehicle speed sensor, a gear position sensor and a handbrake sensor.

[0007] Furthermore, the support leg in place sensor includes a left front horizontal support leg in place sensor, a right front horizontal support leg in place sensor, a left rear horizontal support leg in place sensor, a right rear horizontal support leg in place sensor, a left front vertical support leg in place sensor, a right front vertical support leg in place sensor, a left rear vertical support leg in place sensor, and a right rear vertical support leg in place sensor, which detects in real time whether the corresponding support leg is retracted into place.

[0008] Correspondingly, a fire truck is also disclosed, comprising the above-mentioned fire truck air suspension suppression system based on outrigger status detection.

[0009] Correspondingly, a suppression method of the fire truck air suspension suppression system based on outrigger status detection is also disclosed, including air suspension adjustment suppression and adjustment recovery; When the vehicle is in outrigger operation, the air suspension adjustment is suppressed; when the vehicle exits outrigger operation, the air suspension adjustment is restored.

[0010] Furthermore, the main controller continuously obtains the vehicle's current speed, parking brake status signal, and gear position signal; When the vehicle speed is less than the set threshold and the parking brake is applied while the vehicle is in neutral, the vehicle is considered stationary. When the vehicle is stationary, it continuously obtains the status of the outrigger position sensor and the opening request of the oil pump power take-off and water pump power take-off; When any outrigger position sensor is not in the fully retracted state or receives a request to open the water pump power take-off or oil pump power take-off, the vehicle outrigger is determined to be in operation, and the air suspension system is adjusted and inhibited, and the automatic adjustment function of the air suspension is suspended; When all the outrigger sensors are in the fully retracted state and the oil pump and water pump power are removed, or the handbrake is released, or the gear is not in neutral, or the vehicle speed reaches the set threshold, the vehicle is determined to have exited the outrigger operation, the air suspension system is adjusted to resume operation, and the automatic adjustment function of the air suspension is restarted.

[0011] Furthermore, when determining the vehicle state, a state determination maintenance threshold is set to prevent misjudgment.

[0012] Beneficial effects: Compared with the prior art, the present invention has the following significant improvements: (1) The present invention introduces the outrigger status, water pump power take-off (PTO) status, and oil pump PTO operating status as criteria for determining whether to enter the outrigger operating mode. This allows for rapid detection of the outrigger operating mode on special engineering vehicles and timely suppression of air suspension adjustment. Furthermore, to ensure driving safety and the effective operation of the air suspension adjustment function during driving, flexible and flexible outrigger operating mode exit conditions are employed, effectively avoiding potential driving safety hazards caused by sensor failures that prevent the vehicle from exiting the outrigger operating mode.

[0013] (2) The present invention realizes a clear full-process closed-loop control design from vehicle status judgment, outrigger operation mode recognition, air suspension suppression, to suppression signal release and system recovery. Each link is closely connected and logically rigorous. At the same time, the triggering conditions and execution actions of each link are clearly defined to ensure that the entire control process is scientific, reasonable, safe and reliable, and to achieve intelligent and precise control of the fire truck air suspension system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a connection diagram of the suppression system of the present invention; Figure 2 Schematic diagram of the inhibition method of the present invention. DETAILED DESCRIPTION

[0015] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0016] The outrigger position sensor is a proximity switch or limit switch used on fire trucks to detect the fully retracted state of the outriggers. It works by sensing the position of the outriggers to determine whether they are fully retracted. When the outriggers are fully retracted, the sensor sends a corresponding signal to the control system, informing it of the full retraction, allowing for subsequent operations or displays, ensuring that the outriggers are safely stowed before the vehicle is driven. The outrigger position sensor can be an inductive proximity switch, which uses the principle of electromagnetic induction to detect the proximity of the metal parts of the outriggers. Alternatively, it can be a mechanical limit switch, which transmits the outrigger position signal based on the mechanical action of the outriggers contacting the switch.

[0017] The oil pump power take-off (PTO) is primarily used to extract power from the fire truck engine and transfer it to the oil pump. It's typically installed between the engine and transmission, connected to the engine's crankshaft or the transmission's input shaft via a connecting mechanism. In situations where boom movement is necessary for rescue operations, the PTO converts the engine's mechanical energy into pump power, pumping hydraulic oil into the fire truck's boom or outrigger cylinders, driving the boom or outriggers to extend or rotate.

[0018] A water pump power take-off (PTO) is a device that transfers engine power to a fire pump. During firefighting operations, it provides sufficient power to pump water from a source (such as a fire hydrant or pool) and deliver it at high pressure to spray equipment like fire hoses or monitors, enabling firefighting and rescue efforts.

[0019] When the vehicle main controller detects a request to turn on the oil pump power take-off or the water pump power take-off, it can be considered that firefighting operations are currently being prepared (generally, large fire trucks with booms need to raise their outriggers when performing operations). In order to ensure the stability of the vehicle body, the adjustment function of the air suspension also needs to be suppressed. In the present invention, this is used as an auxiliary judgment condition for whether to enter the outrigger operation mode.

[0020] like Figure 1 As shown, the main controller and chassis controller of the fire truck communicate in real time via a bus to achieve coordinated control. In this solution, the chassis controller receives the current vehicle speed, gear position, and handbrake signals and forwards them to the main controller. The main controller determines whether the vehicle is currently stationary based on the above information. At the same time, it continuously obtains the status of all the vehicle's outrigger position sensors and the water pump power take-off and oil pump power take-off activation requests to comprehensively determine whether it is in outrigger operation mode. When the main controller determines that it is in outrigger operation mode, it immediately sends an air suspension adjustment inhibition command to the chassis controller to suspend the air suspension automatic adjustment function. During this process, the main controller will comprehensively determine whether to exit the outrigger operation mode based on the status of the outrigger position sensors, the water pump power take-off and oil pump power take-off status, and the vehicle speed, gear position, and handbrake status information. If exiting, the main controller immediately sends an air suspension adjustment recovery command to the chassis controller to restore the air suspension automatic adjustment function.

[0021] Corresponding outrigger position sensors are installed on each of the fire truck's four horizontal outriggers and four vertical outriggers (front left, front right, rear left, and rear right). These sensors detect in real time whether the corresponding outrigger has fully retracted, providing basic data for subsequent decisions about whether to enter or exit outrigger operation mode.

[0022] like Figure 2As shown, the main controller continuously acquires the vehicle's current speed, parking brake status, and gear position. If the vehicle's current speed is less than a preset speed threshold (for example, 2 km / h, determined based on a comprehensive consideration of factors such as fire truck operational characteristics, site conditions, and safety requirements; it is generally assumed that a vehicle below this speed is relatively stationary), the parking brake is engaged, and the gear is in neutral, and if all three conditions are met for a duration greater than or equal to a preset threshold (for example, 2 seconds, to prevent brief speed fluctuations from misidentifying the vehicle as stationary and to filter out occasional deceleration disturbances), the vehicle is considered stationary. Continuous monitoring is maintained even after the vehicle comes to a standstill. Throughout the monitoring process, if the vehicle's speed exceeds the preset speed threshold, the parking brake is released, or the gear is not in neutral, the vehicle is immediately deemed to have exited the stationary state.

[0023] When the vehicle is stationary, it continuously obtains the status of all outrigger position sensors installed on the vehicle, and continuously monitors whether it has received an activation request from the water pump power take-off or the oil pump power take-off (this is done to prevent the outrigger position sensor from malfunctioning and failing to detect outrigger extension, resulting in failure to activate the outrigger operation mode). At this time, as long as it detects that one outrigger position sensor is not in the fully retracted state or receives an activation request from the water pump power take-off or the oil pump power take-off, and the duration of this state is greater than or equal to the set time threshold (for example, 0.2 seconds, this is to quickly activate the outrigger operation mode and ensure timely execution of the air suspension suppression command), the main controller will determine that the vehicle has entered the outrigger operation mode.

[0024] Once the vehicle enters outrigger operation mode, the main controller immediately sends an air suspension inhibit signal to the chassis controller, suspending automatic air suspension height adjustment for each axle. This is because the air suspension system automatically adjusts during outrigger operation, potentially causing the suspension height to be too low after the tires are off the ground. When the outriggers are retracted at the end of the operation, the air suspension may be unable to lift the chassis due to a temporary lack of air supply, potentially causing interference with the apron and damaging the suspension system. Sending the air suspension inhibit signal prevents over-adjustment, ensuring that the tires do not interfere with the apron after the operation, ensuring safe driving and preventing damage to the suspension hardware.

[0025] When the vehicle completes the outrigger operation, the air suspension suppression signal needs to be released. Considering that the vehicle is in a driving state in most cases, the air suspension needs to be adjusted in real time to ensure driving safety. Therefore, the exit conditions of the outrigger operation mode are relatively flexible. The specific method is as follows: (1) When the main controller detects that all vertical outriggers are in a fully retracted state and the oil pump and water pump are removed, (2) or it detects that the handbrake is released (3) or the gear is not in neutral (4) or the vehicle speed is greater than the set threshold (such as 1km / h), as long as any of the above conditions is detected and maintained for a time greater than or equal to the set time threshold (such as 0.5 seconds), the main controller sends a recovery signal to the chassis controller to re-enable the automatic adjustment function of the air suspension height of each wheel axle of the vehicle to ensure that the air suspension system can work normally under the vehicle driving conditions.

Claims

1. A fire truck air suspension suppression system based on outrigger status detection, characterized by: The main controller of the fire truck communicates with the chassis controller to coordinate and control the air suspension system; The main controller is connected to the outrigger position sensor, the oil pump power take-off and the water pump power take-off; The chassis controller is connected to a vehicle speed sensor, a gear position sensor and a handbrake sensor.

2. The fire truck air suspension suppression system based on outrigger status detection according to claim 1, characterized in that: The outrigger position sensors include a left front horizontal outrigger position sensor, a right front horizontal outrigger position sensor, a left rear horizontal outrigger position sensor, a right rear horizontal outrigger position sensor, a left front vertical outrigger position sensor, a right front vertical outrigger position sensor, a left rear vertical outrigger position sensor, and a right rear vertical outrigger position sensor, which detect in real time whether the corresponding outrigger is retracted into position.

3. A fire truck, characterized in that: The invention comprises the fire truck air suspension suppression system based on outrigger status detection as described in claim 1.

4. The suppression method of the fire truck air suspension suppression system based on outrigger status detection according to claim 1, characterized in that: Includes air suspension adjustment suppression and adjustment recovery; When the vehicle is in outrigger operation, the air suspension adjustment is suppressed; when the vehicle exits outrigger operation, the air suspension adjustment is restored.

5. The suppression method of the fire truck air suspension suppression system based on outrigger status detection according to claim 4, characterized in that: The main controller continuously obtains the vehicle's current speed, parking brake status signal and gear position signal; When the vehicle speed is less than the set threshold and the parking brake is applied while the vehicle is in neutral, the vehicle is considered stationary. When the vehicle is stationary, it continuously obtains the status of the outrigger position sensor and the opening request of the oil pump power take-off and water pump power take-off; When any outrigger position sensor is not in the fully retracted state or receives a request to open the water pump power take-off or oil pump power take-off, the vehicle outrigger is determined to be in operation, and the air suspension system is adjusted and inhibited, and the automatic adjustment function of the air suspension is suspended; When all the outrigger sensors are in the fully retracted state and the oil pump and water pump power are removed, or the handbrake is released, or the gear is not in neutral, or the vehicle speed reaches the set threshold, the vehicle is determined to have exited the outrigger operation, the air suspension system is adjusted to resume operation, and the automatic adjustment function of the air suspension is restarted.

6. The method for suppressing the air suspension suppression system of a fire truck based on outrigger status detection according to claim 4, characterized in that: When determining the vehicle status, a status determination maintenance threshold is set to prevent misjudgment.

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