Fuel cell collision safety protection method for forklift
By installing ultrasonic radar and collision sensors on the forklift combined with the integrated control of hydrogen sensors, safety hazards during the collision of fuel cell forklifts are solved, safety protection and rapid recovery are achieved, and accident risk is reduced.
Patent Information
- Application Number
- CN202410153136.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-02
- Publication Date
- 2025-08-05
AI Technical Summary
The existing forklift fuel cell system lacks effective safety protection measures during collisions, resulting in high risk of hydrogen leakage and accidents. The existing sensor detection and control have misjudgment and limitations, affecting driving experience and safety.
Multiple ultrasonic radars and collision sensors are used to detect the collision position and intensity, combined with hydrogen sensors to monitor the concentration, and comprehensive analysis is carried out through the vehicle controller to automatically control the drop of the fork, hydrogen supply cutoff and system self-inspection to ensure safety.
Effectively avoid hydrogen leakage and cargo drop, reduce accident losses, provide collision warning, ensure personnel safety and quickly restore normal operation of the system.
Smart Images
Figure CN120423477A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of forklifts, and in particular to a collision safety protection method for a fuel cell used in a forklift. Background Art
[0002] With the increasing use of fuel cells in forklifts, safety requirements for forklifts are becoming increasingly stringent. Hydrogen is a flammable and explosive fuel, posing a significant safety risk. However, fuel cell forklift standards currently lack collision safety requirements. A collision can damage hydrogen cylinders, pipelines, and other hydrogen-related components, leading to hydrogen leaks. Forklifts are typically not equipped with collision safety systems, making it impossible to implement protective measures to prevent hydrogen leaks in the event of a collision, potentially resulting in accidents.
[0003] Hydrogen is a flammable and explosive fuel, posing a significant safety hazard. An accident could cause an emergency power outage on the entire vehicle, preventing the hydrogen cylinder valve from closing and potentially causing the forked cargo to fall. If a leak develops in the hydrogen pipeline, even with a hydrogen sensor, a power outage would render it unable to control the leak, preventing the hydrogen cylinder valve from being closed in time and potentially causing a secondary accident.
[0004] Existing technologies simply add pressure sensors or similar sensors to the vehicle's surface. These sensors detect pressure locally and then initiate protection, cutting off the hydrogen supply and controlling the vehicle to initiate emergency measures such as power outages and braking. These localized pressure sensors have limitations and the potential for misjudgment, causing driver discomfort and impacting vehicle operation.
[0005] The vehicle body acts as a barrier to the fuel cell and the vehicle's electrical circuits. By adding a collision safety system to the vehicle's surface, the system detects the incident at the moment of an accident, even before the vehicle loses power, and immediately cuts off the hydrogen supply, effectively preventing hydrogen leaks. Simultaneously, the forks automatically lower to prevent cargo from falling, causing financial losses or even personal injury. Accidents can occur within seconds, and proactive response can significantly reduce the resulting losses. Summary of the Invention
[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides a collision safety protection method for a fuel cell used in a forklift. The technical solution is as follows:
[0007] A method for collision safety protection of a fuel cell for a forklift, comprising the following steps:
[0008] When a collision occurs, detect the collision position and collision intensity;
[0009] The step of executing collision intensity judgment includes: executing an emergency treatment step when the collision intensity at the collision position is greater than the corresponding collision intensity threshold; otherwise, executing a system self-check step; the step of executing emergency treatment includes: shutting down the output of the hydrogen storage device and controlling the fork to descend;
[0010] After completing the emergency treatment steps, the hydrogen concentration detection step is executed; when the hydrogen concentration signal is greater than the hydrogen concentration threshold, the vehicle power-off step is executed; when the hydrogen concentration signal is less than the hydrogen concentration threshold, the system self-check step is executed;
[0011] After executing the system self-check step, if the system self-check result is abnormal, execute the step of powering off the entire vehicle.
[0012] Furthermore, in the step of collision intensity judgment, the collision position is obtained by simulating and calculating the detection values of multiple installed obstacle detection devices; the collision intensity is obtained by simulating and calculating the collision values of multiple collision intensity detection devices; and the collision intensity threshold is a safety collision threshold set after comprehensively analyzing the structural strength of the collision position and the position of hydrogen-related pipelines.
[0013] Furthermore, it also includes: after executing the system self-check step, when the system self-check result is normal, executing the restart step; the restart step includes: restarting the hydrogen storage device output and starting the fuel cell system.
[0014] Furthermore, the method further includes: executing a collision warning step before a collision occurs.
[0015] Furthermore, the collision warning step includes: when an obstacle is detected in the direction of travel, an audible and visual alarm will be provided to the driver, and the deceleration will be automatically controlled to actively avoid collision.
[0016] Furthermore, in the emergency handling step, the fork is lowered at a constant speed.
[0017] Furthermore, collision sensors are used to detect collision intensity; the collision sensors are arranged in multiple locations, including: on both sides of the battery compartment and the grid of the battery cover, and near the hydrogen filling port and hydrogen pipeline.
[0018] Furthermore, an ultrasonic radar is used to detect the collision position; the ultrasonic radar is set in multiple locations, including: on both sides of the battery compartment and the grille of the battery cover, and near the hydrogen filling port and hydrogen pipeline.
[0019] Furthermore, a hydrogen sensor is used to detect hydrogen concentration; the hydrogen sensor can be set in multiple locations, including: above the hydrogen storage device, above the hydrogen pipeline and above the fuel cell.
[0020] Furthermore, the hydrogen sensor is a hydrogen catalytic combustion sensor.
[0021] The present invention achieves the following technical effects:
[0022] 1. The present invention can automatically monitor whether the forklift is safe after a collision and take timely control measures to effectively avoid hydrogen leakage, which may lead to more serious accidents such as combustion and explosion, thereby ensuring personnel safety and reducing property losses.
[0023] 2. The present invention provides system self-check and fuel cell restart after a collision, quickly determines the consequences of the collision, and automatically restores the forklift status when there is no abnormality in the system, thereby allowing the forklift to continue normal use in the event of a minor collision.
[0024] 3. The present invention integrates multiple signals to calculate the collision intensity and collision location, and can quickly determine the consequences of the collision by integrating the collision intensity, the structural strength of the collision location and the location of hydrogen-related pipelines, thereby allowing the forklift to continue normal use in the event of a minor collision.
[0025] 4. The present invention also provides collision warning, which can actively and effectively avoid collisions through sound and light alarms and automatic linear control deceleration. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 is a system block diagram of the forklift fuel cell collision safety protection system of the present invention;
[0027] Figure 2 This is a schematic diagram of the installation location of the ultrasonic radar and collision sensor of the fuel cell forklift;
[0028] Figure 3 The present invention relates to a collision safety protection method for a fuel cell for a forklift. DETAILED DESCRIPTION
[0029] To further illustrate various embodiments, the present invention provides accompanying drawings. These drawings form part of the present disclosure and are primarily used to illustrate the embodiments and, in conjunction with the relevant description in the specification, to explain the operating principles of the embodiments. By referring to these drawings, those skilled in the art will be able to understand other possible implementations and the advantages of the present invention.
[0030] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.
[0031] like Figure 1 and Figure 2As shown, the present invention provides an embodiment of a fuel cell collision safety protection system for a forklift. The system comprises a hydrogen sensor, ultrasonic radar, collision sensor, and a vehicle control unit (ECU). The ECU connects to the fuel cell module and lithium battery module via a data bus such as the CAN bus to control the output power of the fuel cell and lithium battery. The ECU is also connected to the forklift's instrument panel and fork control system via wiring harnesses, displaying alarm information on the instrument panel and controlling the raising and lowering of the forks.
[0032] For fuel cell forklifts, in order to increase the intake and exhaust volume and ensure output power, larger grilles are required on both sides of the battery compartment and the battery cover. This will reduce the structural strength of these parts to a certain extent, and weaken the protection of the fuel cell. Therefore, the collision safety system mainly monitors these structural weak parts and will Figure 2 Ultrasonic radar and collision sensors are installed in areas 2 and 4 as shown, especially near the hydrogen filling port and hydrogen pipeline (such as Figure 2 Area 3 and Area 1 shown). When the collision sensor detects a signal, it transmits it to the controller in real time. The controller analyzes and makes different controls based on the signal strength and the hydrogen sensor signal.
[0033] Ultrasonic radar senses obstacles close to the vehicle and provides collision warnings to the driver, significantly reducing the likelihood of collisions and protecting the vehicle. When the collision sensor detects a collision, it transmits the signal to the controller. The controller combines the ultrasonic radar and collision sensor signals, uses an algorithm to determine the authenticity, location, and intensity of the collision, and then combines the hydrogen concentration signal for comprehensive analysis and appropriate control.
[0034] When the ultrasonic radar detects an obstacle in the direction of travel, it provides an audible and visual warning to the driver and automatically controls the vehicle's deceleration linearly, effectively and proactively avoiding a collision. However, when a collision occurs passively, the controller uses the impact location detected by the ultrasonic radar to determine the structural strength of the area, combined with the collision signal strength detected by the collision sensor, to implement reasonable and safe control based on pre-set judgment logic.
[0035] Most collision sensors use an inertial mechanical switch structure, acting as a control switch. Their operating state depends on the magnitude of the vehicle's acceleration during a collision. They can be categorized by structure as either mechanical or electronic. Mechanical types include rolling ball, roller, and eccentric ball. Collision sensors typically serve as control signal input devices for airbag systems. In this application, they are used solely to detect collision intensity.
[0036] Multiple hydrogen sensors are usually installed in locations such as hydrogen cylinders, hydrogen pipelines, and above fuel cells to monitor whether hydrogen leaks occur.
[0037] Preferably, the hydrogen sensor used is a hydrogen catalytic combustion sensor. The hydrogen catalytic combustion sensor has the following advantages:
[0038] High sensitivity: Due to the presence of the catalyst, the hydrogen leak sensor is very sensitive to hydrogen detection and can detect hydrogen concentrations as low as tens of ppm.
[0039] Fast response: The catalytic combustion reaction of the sensor can generate a large amount of heat in a short period of time, making the sensor's response speed very fast and able to quickly detect changes in hydrogen concentration.
[0040] High reliability: The hydrogen leak sensor based on catalytic combustion reaction has high stability and reliability, and can maintain relatively stable performance during long-term use.
[0041] The present invention provides a collision safety protection method for a fuel cell used in a forklift, which is described as follows:
[0042] First, the forklift is powered on and the fuel cell is started (step S1). When the forklift is moving, the ultrasonic radar senses obstacles close to the vehicle and provides a collision warning to the driver (step S2). When the vehicle collides, the collision sensor will output a collision value, and the collision value will be fed back to the controller (step S3). The controller will determine the collision position based on the ultrasonic radar and detect whether the collision value is greater than the set threshold (step S4). If the collision value is greater than the set threshold, the controller sends an instruction to immediately close the hydrogen cylinder valve to ensure that no hydrogen leaks; at the same time, it automatically controls the fork to descend (preferably automatically and at a uniform speed) to avoid secondary accidents; at this time, the entire vehicle will operate in pure electric mode (step S5). Currently, the vehicle is powered by lithium batteries such as ternary lithium or lithium iron phosphate in pure electric mode, so its pure electric mode is also called pure lithium battery mode.
[0043] At the same time, the vehicle controller will judge the received hydrogen concentration sensor value (step S6). When the hydrogen concentration value exceeds the preset threshold, the vehicle will be forced to power off (step S7). When the value of the hydrogen concentration sensor is less than the set threshold, it means that the risk of hydrogen leakage is slight, and the vehicle electronic control system can be further self-checked to detect whether the various technical parameters of the vehicle meet the requirements and whether there is a fault code triggered (step S8), and judge according to the system self-check result (step S9). If the detection indicators are normal, the vehicle can open the hydrogen bottle valve (step S10), the fuel cell system restarts (step S11), and the vehicle is used normally. If the system self-check result is abnormal, it shows that the vehicle has been substantially damaged, and the vehicle will be forced to power off (step S7).
[0044] When checking whether the collision value is greater than the set threshold (step S4), if the collision value is less than the set threshold, combined with the distance and position of the collision object detected by the ultrasonic radar, the vehicle's electronic control system self-checks to check whether the vehicle's various technical parameters meet the requirements and whether any fault codes are triggered (step S8). The processing after the system self-check is as above. If the test indicators are normal, the vehicle can be used normally.
[0045] The specific process is as follows Figure 3 shown.
[0046] In step S4, the collision intensity threshold is related to the collision location. This system is equipped with multiple ultrasonic radars and collision sensors. The collision location is determined based on detection signals received by the multiple ultrasonic radars. Each ultrasonic radar detects the distance between the vehicle and the obstacle approaching it, transmits the signal to the controller, and uses an algorithm to simulate and calculate the collision location. Simultaneously, the controller receives collision signals output by each collision sensor and simulates the collision intensity at the collision location based on these collision signals. This is combined with safety collision thresholds set for each location of the vehicle after strength analysis. The collision intensity, structural strength at the collision location, and the location of hydrogen-related pipelines are then combined to determine the consequences of the collision and further determine the necessary control measures for the vehicle.
[0047] This method can automatically monitor whether the forklift is safe after a collision and take timely control measures to effectively avoid hydrogen leakage that may lead to more serious accidents such as combustion and explosion, thereby ensuring personnel safety and reducing property losses.
[0048] Although the present invention has been particularly shown and described in conjunction with preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made to the present invention without departing from the spirit and scope of the invention as defined in the appended claims, and all such changes are within the scope of protection of the present invention.
Claims
1. A method for collision safety protection of a fuel cell for a forklift, characterized in that: The following steps are involved: When a collision occurs, detect the collision position and collision intensity; A step of executing collision intensity determination: when the collision intensity at the collision position is greater than a corresponding collision intensity threshold, executing an emergency processing step; Otherwise, the system self-check step is executed; the emergency treatment step includes: shutting down the output of the hydrogen storage device and controlling the fork to descend; After completing the emergency treatment steps, the hydrogen concentration detection step is executed; when the hydrogen concentration signal is greater than the hydrogen concentration threshold, the vehicle power-off step is executed; when the hydrogen concentration signal is less than the hydrogen concentration threshold, the system self-check step is executed; After executing the system self-check step, if the system self-check result is abnormal, execute the step of powering off the entire vehicle.
2. The forklift fuel cell collision safety protection method according to claim 1, characterized in that: In the step of collision intensity judgment, the collision position is obtained by simulating and calculating the detection values of multiple installed obstacle detection devices; the collision intensity is obtained by simulating and calculating the collision values of multiple collision intensity detection devices; the collision intensity threshold is a safety collision threshold set after comprehensively analyzing the structural strength of the collision position and the position of hydrogen-related pipelines.
3. The forklift fuel cell collision safety protection method according to claim 1, characterized in that: It also includes: after executing the system self-check step, when the system self-check result is normal, executing the restart step; the restart step includes: restarting the hydrogen storage device output and starting the fuel cell system.
4. The forklift fuel cell collision safety protection method according to claim 1, characterized in that: The method also includes: executing a collision warning step before a collision occurs.
5. The forklift fuel cell collision safety protection method according to claim 4, characterized in that: The collision warning step includes: when an obstacle is detected in the direction of travel, an audible and visual alarm will be provided to the driver, and the deceleration will be automatically controlled to actively avoid a collision.
6. The forklift fuel cell collision safety protection method according to claim 1, characterized in that: In the emergency handling step, the fork is lowered at a constant speed.
7. The forklift fuel cell collision safety protection method according to claim 1, characterized in that: Collision intensity detection is performed using collision sensors; the collision sensors are located in multiple locations, including: on both sides of the battery compartment and the grid of the battery cover, and near the hydrogen filling port and hydrogen pipeline.
8. The forklift fuel cell collision safety protection method according to claim 1, characterized in that: Ultrasonic radar is used to detect the collision position; the ultrasonic radar is set in multiple locations, including: on both sides of the battery compartment and the grid of the battery cover, and near the hydrogen filling port and hydrogen pipeline.
9. The forklift fuel cell collision safety protection method according to claim 1, characterized in that: A hydrogen sensor is used to detect hydrogen concentration; the hydrogen sensor can be set in multiple locations, including: above the hydrogen storage device, above the hydrogen pipeline, and above the fuel cell.
10. The forklift fuel cell collision safety protection method according to claim 9, characterized in that: The hydrogen sensor is a hydrogen catalytic combustion sensor.