Scissor-type aerial work platform walking brake control system and method

Abstract

The present application relates to the technical field of scissor forklift brake control, and discloses a scissor aerial work platform walking brake control system and method, an operation handle enables a key reset and triggers a brake request, realizes initialization and triggering of a brake control sequence; monitors the scissor forklift state and collects slope and load information, realizes synchronous acquisition of external environment conditions and internal load state through real-time calling of data of an inclination sensor and a pressure sensor; for fast brake braking of the scissor forklift, based on the real-time collected data, a three-stage collaborative braking strategy of speed reduction, pressure relief and shutdown is adopted, based on the real-time collected slope information, the switching timing between stages is adaptively adjusted, the brake process is accurately matched with dynamic load and terrain conditions, so that the effect of considering brake efficiency and terminal parking stability under the premise of no mechanical wear is achieved; the scissor forklift is braked and tends to be stopped stably. Fast, stable and adaptive to different conditions can be realized.

Description

Technical Field

[0001] This invention relates to the field of scissor lift braking control technology, and in particular, to a scissor lift aerial work platform traveling brake control system and method. Background Technology

[0002] As a common type of aerial work platform, the performance of the travel braking control system of a scissor lift directly affects the safety and stability of the equipment's operation. Traditional scissor lifts require frequent starts and stops during movement. Existing braking systems mostly use hydraulic circuit-based braking methods, with the typical control logic as follows: The operator issues a travel or stop command via a handle. After receiving the handle signal, the electronic control unit (ECU) controls the motor driver to drive the DC motor, which in turn drives the oil pump to supply oil to the hydraulic system. The ECU then controls the opening and closing of the forward / reverse valves to achieve travel and stopping.

[0003] In practical applications, the above-mentioned traditional braking control methods have the following problems:

[0004] First, during braking, when the operator releases the lever enable signal, the ECU determines that braking has begun, but it will continue to output the motor enable signal until the throttle signal returns to zero. During this process, the motor stops rotating, causing changes in the oil pressure in the hydraulic circuit. Some hydraulic oil returns to the oil tank through the return line, while the other part flows back due to the pressure drop, which can easily cause the motor to reverse, resulting in secondary braking of the vehicle or violent shaking of the platform, seriously affecting the stability of the equipment and operational safety.

[0005] Secondly, when the operator slowly pushes the lever back to the neutral position to achieve deceleration, the ECU controls the throttle signal output according to the preset deceleration curve. If the lever returns to the neutral position too slowly, the voltage output to the driver will be too low, resulting in insufficient pump motor speed and inability to effectively drive the hydraulic motor. At this time, although the motor is still rotating, the vehicle has already stopped prematurely. Although secondary braking can be avoided in this situation, the braking distance is significantly extended, which can easily lead to collisions in confined spaces or near obstacles. In addition, traditional hydraulic brakes often slip on slopes due to response delays or insufficient hydraulic pressure, posing a safety hazard. Summary of the Invention

[0006] This invention provides a scissor lift aerial work platform travel braking control system and method, which can achieve fast, stable and adaptive braking under different working conditions, overcoming the technical problems of slow braking response, secondary impact, slope slippage and insufficient braking distance control accuracy in the prior art.

[0007] According to one aspect of the present invention, a method for controlling the travel braking of a scissor lift aerial work platform is provided, comprising the following steps: S100, resetting the enable button on the operating handle and triggering a braking request to initialize and trigger the braking control sequence; S200, monitoring the scissor lift status and collecting slope and load information, and synchronously acquiring external environmental conditions and internal load status by calling data from tilt sensors and pressure sensors in real time; S300, for rapid braking of the scissor lift, based on the real-time collected data, adopting a three-level coordinated braking strategy of speed reduction, pressure relief, and shutdown, and adaptively adjusting the switching sequence between each level based on the real-time collected slope information to achieve precise matching between the braking process and dynamic load and terrain conditions, thereby achieving the effect of balancing braking efficiency and terminal parking stability without mechanical wear; S400, the scissor lift braking is completed and tends to stop smoothly.

[0008] Further, step S300 specifically includes the following steps: S301, when the ECU (Electronic Control Unit) receives the braking signal from the PCU (handle), the ECU (Electronic Control Unit) first continuously outputs an enable signal to enable the controller to continue controlling the travel motor to reduce speed, and sets the throttle signal duty cycle to 15-25%, so that the scissor lift quickly changes from high speed to low speed, thereby eliminating the main inertia, achieving smooth initial deceleration, and reducing hydraulic shock; S302, based on the characteristics of the hydraulic system, the difference in the speed of the oil pump motor is controlled to generate counteracting oil pressure to achieve a deceleration effect, thereby bringing the scissor lift to a stop; S303, after the oil pressure in the hydraulic circuit stabilizes, the control signal and the hydraulic circuit are cut off to ensure that the scissor lift stops smoothly.

[0009] Further, step S303 specifically includes: S3031, collecting the input value of the tilt sensor and determining the current slope of the scissor lift; S3032, when the slope is greater, the time for cutting off the control signal and the hydraulic circuit when the hydraulic pressure in the hydraulic circuit stabilizes is reduced; when the slope is smaller, the time for cutting off the control signal and the hydraulic circuit when the hydraulic pressure in the hydraulic circuit stabilizes is increased.

[0010] Furthermore, the throttle signal duty cycle setting in step S301 is adjusted according to the load of the scissor lift; the higher the scissor lift's own weight and load, the greater the inertia, and the larger the duty cycle setting, and vice versa.

[0011] Further, step S301 specifically involves: the controller reading state parameters in real time, including the current slope angle θ measured by the tilt sensor, and the current platform load m obtained by the pressure sensor or load calculation module; based on the read slope and load information, the controller substitutes the preset algorithm model D=15%+0.1m+0.05·tanθ to dynamically calculate the optimal oil pump motor duty cycle required at the moment, so as to ensure the precise matching of braking force with vehicle kinetic and potential energy, with vehicle kinetic energy positively correlated with load and potential energy positively correlated with slope.

[0012] Furthermore, the controller outputs commands to the motor driver to maintain the enable signal and adjusts the throttle signal to the calculated target duty cycle value, controlling the oil pump motor to enter the specified operating condition.

[0013] Further, step S302 specifically involves: due to the inertia of the scissor lift itself and the characteristics of hydraulic oil drive, the hydraulic oil pressure delivered by the motor at high speed is much higher than that delivered by the motor at low speed. The two oil lines counteract each other, thereby achieving the effect of deceleration. At this time, the scissor lift will switch to a stopped state.

[0014] Furthermore, the hydraulic system responds to the controller's command and enters the oil pressure counter-current state, that is, the hydraulic oil generated during high-speed travel and the low-pressure oil generated by the oil pump during low-speed operation counter-current in the oil circuit, rapidly consuming the vehicle's kinetic energy and achieving smooth deceleration.

[0015] Further, step S303 specifically involves: waiting for the hydraulic oil delivered during high-speed rotation to return, and then for the hydraulic oil delivered during low-speed rotation of the motor to stabilize, the scissor lift resumes slow movement or stops. At this time, the solenoid valve is closed to cut off the enable and throttle signals, and the scissor lift comes to a steady stop.

[0016] Furthermore, the controller continuously monitors the pressure change rate and / or pressure difference of the main oil circuit; determines whether the hydraulic system pressure has stabilized, i.e., whether the pressure fluctuation is below the preset threshold; if not, it returns to step S301 and continues to maintain the current output state; if yes, the hydraulic system pressure has stabilized, indicating that the scissor lift has come to a stop and the hydraulic shock has been effectively absorbed, and the controller immediately issues the final stop command: closes the forward solenoid valve or the reverse solenoid valve, and completely cuts off the oil pump motor enable and throttle signal.

[0017] Furthermore, in step 303, if pressure stability is not detected within a predetermined time, it is determined to be an abnormal situation, and the safety redundancy mechanism is automatically triggered to directly activate the mechanical brake or the highest priority braking command to ensure safety.

[0018] According to another aspect of the present invention, a scissor lift aerial work platform travel braking control system is also provided for implementing the above-mentioned scissor lift aerial work platform travel braking control method, including a controller, an inclination sensor, a pressure sensor, a motor driver, and a handle; the controller is electrically connected to the inclination sensor, the pressure sensor, the motor driver, and the handle respectively.

[0019] The present invention has the following beneficial effects:

[0020] 1. Improved accuracy and adaptability of braking process: By acquiring slope and load information in real time and using these key operating parameters as direct inputs for control decisions, the braking control system can break free from the limitations of traditional fixed parameter control mode; the braking control system no longer mechanically executes the preset deceleration curve, but can dynamically sense and respond to changes in the external environment (slope) and internal state (load), achieving precise matching between braking strategy and real-time operating conditions.

[0021] 2. Effectively eliminates secondary impacts and swaying during braking: By adopting a three-stage coordinated braking strategy of "speed reduction, pressure relief, and shutdown," the braking process is managed in a refined time sequence. In particular, the introduction of the "pressure relief" stage can smoothly release the residual pressure in the hydraulic circuit, thereby fundamentally avoiding the phenomenon of secondary braking of the vehicle caused by sudden changes in oil pressure or motor reversal. This significantly reduces the swaying amplitude of the platform during emergency braking, greatly improving the stability of the work platform and the comfort and safety of the operators.

[0022] 3. Ensures the reliability and safety of parking on slopes: Based on real-time slope information, the braking timing is adaptively adjusted, enabling the braking system to automatically strengthen the braking logic under slope conditions. This effectively overcomes the risk of slippage on slopes caused by traditional hydraulic brakes due to response delay or insufficient holding force, ensuring that the vehicle can be reliably parked under various slope conditions and eliminating safety hazards.

[0023] 4. Improved consistency of braking distance: Through adaptive control, regardless of the speed of the lever return, the braking system can calculate the optimal braking parameters based on the current load and slope, thereby reducing the unpredictability of braking results, avoiding the problem of excessively long braking distance caused by the slow return speed of the lever, and the risk of collision when approaching obstacles, making the parking position more controllable and accurate.

[0024] 5. Achieves non-mechanical wear braking: The entire braking process is achieved through precise control of the hydraulic system and motor drive by the electronic control system, without relying on additional mechanical friction braking devices. This avoids component wear, aging, and performance degradation caused by mechanical friction, which not only improves the reliability of the system but also reduces maintenance costs.

[0025] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0026] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0027] Figure 1 This is a flowchart of the steps of the preferred embodiment of the scissor lift aerial work platform travel braking control method of the present invention;

[0028] Figure 2 This is a schematic diagram of the hydraulic system according to a preferred embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of brake control according to a preferred embodiment of the present invention;

[0030] Figure 4 This is a schematic diagram of the walking brake control system of a scissor lift aerial work platform according to a preferred embodiment of the present invention;

[0031] Figure 5 This is a comparison curve of the uphill braking of the simulated experimental data curve of a preferred embodiment of the present invention. Figure 5 (a) is the braking curve diagram of the traditional method. Figure 5 (b) is a diagram of the braking curve of the three-level collaborative strategy. Detailed Implementation

[0032] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0033] like Figure 1As shown, the scissor lift aerial work platform travel braking control method of this embodiment includes the following steps: S100, the operating handle enable button is reset and a braking request is triggered to initialize and trigger the braking control sequence; S200, the scissor lift status is monitored and slope and load information are collected. By calling the data of the tilt sensor and pressure sensor in real time, the external environmental conditions and internal load status are synchronously acquired; S300, for the rapid braking of the scissor lift, based on the real-time collected data, a three-level coordinated braking strategy of speed reduction, pressure relief and shutdown is adopted. Based on the real-time collected slope information, the switching sequence between each level is adaptively adjusted to achieve precise matching between the braking process and dynamic load and terrain conditions, thereby achieving the effect of balancing braking efficiency and terminal parking stability without mechanical wear; S400, the scissor lift braking is completed and tends to stop smoothly. This invention relates to a scissor lift aerial work platform travel braking control method. By synchronously acquiring slope and load information in real time and using these key operating parameters as direct inputs for control decisions, the braking control system can break free from the limitations of traditional fixed-parameter control modes. The braking control system no longer mechanically executes a preset deceleration curve but can dynamically sense and respond to changes in the external environment (slope) and internal state (load), achieving precise matching between the braking strategy and real-time operating conditions. By employing a three-level coordinated braking strategy of "deceleration, pressure relief, and shutdown," the braking process is managed with refined timing. In particular, the introduction of the "pressure relief" stage smoothly releases residual pressure in the hydraulic circuit, fundamentally avoiding secondary braking caused by sudden oil pressure changes or motor reversal. This significantly reduces the platform's sway during emergency braking, greatly improving the stability of the work platform and the comfort and safety of the operators. Based on real-time slope information... The adaptive braking timing system automatically enhances braking logic on inclines, effectively overcoming the risk of slippage on inclines caused by response delays or insufficient holding force in traditional hydraulic brakes. This ensures reliable parking of the vehicle under various incline conditions, eliminating safety hazards. Through adaptive control, regardless of the lever's return speed, the braking system calculates optimal braking parameters based on the current load and incline, reducing the unpredictability of braking results and avoiding excessively long braking distances due to slow lever return speeds, as well as potential collision risks when approaching obstacles. This makes parking positions more controllable and accurate. The entire braking process is achieved through precise control of the hydraulic system and motor drive by the electronic control system, eliminating the need for additional mechanical friction braking devices. This avoids component wear, aging, and performance degradation caused by mechanical friction, improving system reliability and reducing maintenance costs.This invention relates to a scissor lift aerial work platform travel braking control method. By introducing multi-sensor information fusion and three-level adaptive cooperative braking, it solves the inherent technical problems of traditional hydraulic braking systems, such as response delay, slope slippage, secondary impact, and poor braking distance control. It realizes a leap from "open-loop fixed program" to "closed-loop dynamic optimization" in the braking process, achieving multiple excellent effects such as improving braking efficiency, ensuring parking stability, enhancing operational safety, and reducing system maintenance.

[0034] like Figure 2 The diagram illustrates the basic operating principle of the hydraulic drive and braking of a scissor lift aerial work platform. During system operation, hydraulic oil originates from the tank, is filtered by the suction filter, pressurized by the hydraulic pump, and then delivered to the core control valve assembly via high-pressure pipelines. The control valve assembly acts as the system switching hub, directing pressurized oil to the hydraulic motor / cylinder to drive the vehicle's movement or platform lifting under normal operating conditions. When braking is required, it switches to braking mode, directing oil to the accumulator / brake valve circuit, achieving smooth deceleration through oil pressure counter-current and energy absorption. The low-pressure oil, after completing its function, is ultimately filtered by the return filter and returned to the tank, forming a complete closed-loop cycle. This provides the hydraulic actuation basis for the invention's achievement of brakes without mechanical wear.

[0035] like Figure 2 As shown, the architecture of the hydraulic execution environment upon which the brake control system of this invention relies includes two core paths for the hydraulic fluid in the working and braking states, providing physical structural support for the braking mechanisms of hydraulic pressure counter-pressure (S302) and pressure relief shut-off (S303) in the brake control method. More specifically, as... Figure 2 As shown, the two circuits of drive (via hydraulic motor / cylinder) and braking (via accumulator / brake valve) are clearly distinguished, which reflects the reusability of the system function and proves that braking without mechanical wear is achieved through the switching of internal circuits and energy management of the hydraulic system. The control valve group, as a key node, is controlled by the electronic control unit (ECU) to realize the switching of the direction and state of the oil circuit. It is the core execution component for implementing the "three-level coordinated braking strategy".

[0036] like Figure 3The control flowchart shown illustrates the decision-making logic and operating principle of the brake control system of this invention. When the operating lever is detected to be zeroed (triggering a brake request), the system first uses an inclination sensor to determine whether the current slope is greater than a preset threshold of 5°. If the determination is "yes" > 5° (slope), the controller immediately and simultaneously activates electronic locking and hydraulic braking. This combines the rigid locking of the mechanical brake with the flexible braking of the hydraulic system, forming a dual guarantee to ensure absolute parking safety under steep slope conditions and completely eliminate the risk of vehicle rollover. If the determination is "no" ≤ 5° (slope), the controller only activates hydraulic braking, achieving smooth deceleration and parking through the aforementioned wear-free methods such as hydraulic counter-pressure. This optimizes braking comfort and energy efficiency under gentle conditions while ensuring safety, demonstrating the intelligent decision-making of this invention based on adaptive switching of braking modes according to operating conditions.

[0037] In this embodiment, step S300 specifically includes the following steps: S301, when the ECU (Electronic Control Unit) receives the braking signal from the PCU (Handle), the ECU (Electronic Control Unit) first continuously outputs an enable signal to enable the controller to continue controlling the travel motor to reduce speed, and sets the throttle signal duty cycle to 15-25%, so that the scissor lift quickly changes from high speed to low speed, thereby eliminating the main inertia, achieving smooth initial deceleration, and reducing hydraulic shock; S302, based on the characteristics of the hydraulic system, the difference in the speed of the oil pump motor is controlled to generate counteracting oil pressure to achieve a deceleration effect, thereby bringing the scissor lift to a stop; S303, after the oil pressure in the hydraulic circuit stabilizes, the control signal and the hydraulic circuit are cut off to ensure that the scissor lift stops smoothly. By setting the throttle signal duty cycle to a relatively low fixed range of 15-25%, the scissor lift is quickly and controllably reduced from high speed to low speed, acting as a primary buffer to avoid the violent impact caused by the throttle signal instantly returning to zero. This creates a smooth initial condition for subsequent fine braking and helps suppress scissor lift sway. The main braking is achieved using the inherent characteristics of the hydraulic system. Precise control of the oil pump motor generates a speed difference opposite to the scissor lift's inertia, thus generating a counteracting oil pressure within the hydraulic system. This counteracting oil pressure efficiently and smoothly absorbs and dissipates the vehicle's kinetic energy, allowing the scissor lift to transition naturally from low speed to a stop, achieving frictionless braking and fundamentally avoiding mechanical wear. The controller does not immediately cut off all passages after the scissor lift stops. Instead, it intelligently waits for the pressure in the hydraulic circuit to reach a stable equilibrium before performing the shut-off operation. This delayed judgment completely eliminates the possibility of the scissor lift jerking or slightly slipping due to oil pressure fluctuations or residual pressure release, thus ensuring that the scissor lift can achieve a stable and smooth stop under various working conditions, improving safety and operational accuracy. The three specific steps of step S300 form a complete logical chain from deceleration to braking to locking. The entire process is progressive, with each stage preparing for the next and each stage consolidating the effect of the previous stage. This structured design makes the braking process logically clear and responsive, and can reliably reproduce a stable braking effect.

[0038] In this embodiment, step S303 specifically includes: S3031, collecting the input value of the tilt sensor to determine the current slope of the scissor lift; S3032, when the slope is greater, the time for cutting off the control signal and hydraulic circuit when the hydraulic pressure stabilizes is reduced; when the slope is smaller, the time for cutting off the control signal and hydraulic circuit when the hydraulic pressure stabilizes is increased. By collecting tilt sensor data in real time, the core variable of the current parking condition, the slope, is accurately identified, enabling the control system to move away from a single fixed time constant, providing a key basis for subsequent intelligent decision-making and ensuring the environmental adaptability of the control strategy; and based on this, a reverse adaptive relationship of "slope-delay" is established. Under steep slope conditions, the hydraulic system reduces the waiting time and can execute the final shut-off (lock-up) operation more quickly; on slopes with a large gravity component, sufficient hydraulic holding force must be quickly established to counteract the tendency to slip, thereby prioritizing the absolute reliability of parking and effectively eliminating the safety hazard of slope slippage. Under gentle slopes or level conditions, the hydraulic system increases the waiting time, allowing sufficient time for residual pressure in the hydraulic circuit to balance and release within the system. This minimizes instability caused by oil pressure fluctuations, such as jerking or slight slippage of the scissor lift, resulting in an extremely smooth and gentle parking experience on flat surfaces, improving operational comfort and platform stability. The hydraulic system no longer passively waits for a fixed time but actively predicts the required locking timing based on the external environment (slope). This adaptive mechanism enables the braking system to exhibit rapid response on steep slopes and gentle braking on gentle slopes, automatically achieving optimal overall braking performance under different conditions—balancing safety and stability.

[0039] In this embodiment, the throttle signal duty cycle setting in step S301 is adjusted according to the scissor lift's load. The higher the scissor lift's weight and load, the greater its inertia, and the larger the duty cycle setting; conversely, the lower the weight and load, the smaller the duty cycle setting. By dynamically adjusting the initial braking duty cycle based on the scissor lift's total weight (weight + load), the system's output initial braking force matches the scissor lift's current actual inertial force. The greater the load, the larger the set duty cycle, meaning the oil pump motor maintains a relatively higher speed in the initial braking phase. This generates a sufficiently large counteracting oil pressure in the hydraulic circuit to counteract the enormous inertia, effectively avoiding problems such as slow deceleration and excessive braking distance due to insufficient braking force. The adaptive adjustment mechanism overcomes the control defects of fixed parameter settings. Regardless of whether the scissor lift is unloaded or heavily loaded, the system can automatically provide an appropriate initial deceleration force, making the deceleration feel and braking process consistent under different load conditions. This eliminates the unpleasant experience of soft braking under heavy loads or excessive braking under unloaded conditions, significantly improving the predictability of operation. The precise setting of the initial duty cycle ensures vehicle stability and avoids control inaccuracies caused by sudden load changes. It lays the foundation for the S302 (using counter-hydraulic braking) and S303 (final shut-off) phases. An initial braking force matched to inertia allows the scissor lift to smoothly transition to low speed in a more controlled and linear manner, avoiding the shock caused by sudden speed drops. This reduces pressure fluctuations in the entire hydraulic system, providing a stable prerequisite for precise control in subsequent phases and ultimately contributing to a smooth and stable braking process. By providing a matching braking force based on the magnitude of inertia, efficient dissipation of kinetic energy is achieved. This avoids both insufficient energy dissipation due to insufficient braking force and energy waste or system shocks that may result from excessive braking force overflow, demonstrating the refinement and intelligence of the control strategy.

[0040] In this embodiment, step S301 specifically involves: the controller reading state parameters in real time, including the current slope angle θ measured by the tilt sensor and the current platform load m obtained by the pressure sensor or load calculation module; based on the read slope and load information, the controller substitutes the preset algorithm model D=15%+0.1m+0.05·tanθ to dynamically calculate the optimal oil pump motor duty cycle required at the moment, so as to ensure the precise matching of braking force with vehicle kinetic energy and potential energy, with vehicle kinetic energy positively correlated with load and potential energy positively correlated with slope. By synchronously reading the slope angle θ and load m, the controller has for the first time quantified and integrated all the main physical factors (kinetic and potential energy) affecting the braking demand of the scissor lift. By executing the preset algorithm model D=15%+0.1m+0.05·tanθ, the system no longer makes simple linear adjustments, but can proactively calculate the optimal braking force required to overcome the current total mechanical energy (kinetic and potential energy) and immediately convert it into a precise duty cycle control command for the oil pump motor, ensuring that the output of the braking force is highly matched with the actual dynamic load of the scissor lift from the initial moment. In the algorithm model, D represents a "delay parameter" or "time adjustment factor" used to control the braking process. Its function is to dynamically adjust the switching timing or execution duration between different stages of the three-level coordinated braking strategy (deceleration, depressurization, and shutdown) based on real-time detected load (m) and slope (θ) information, thereby achieving a "precise match" between the braking process and dynamic load and terrain conditions. The constant term (15%) establishes the basic braking force under the baseline working condition (level road surface, unloaded). The load compensation term (+0.1m) directly corresponds to the magnitude of the scissor lift's kinetic energy (E). k ∝½mv², E k (where m is kinetic energy, v is mass, and v is velocity), achieving a direct proportional adjustment between braking force and inertial load, ensuring consistent deceleration under different loads, and avoiding insufficient braking under heavy loads or overshooting under no-load conditions; the slope compensation term (+0.05·tanθ) directly corresponds to the component of gravitational potential energy in the slope direction (E p ∝mgh, where E pLet F be the gravitational potential energy, m be the mass, g be the gravitational acceleration, and h be the height. On the inclined plane, this manifests as the sliding force F∝mg·sinθ≈mg·tanθ, where F is the sliding force, m is the mass, g is the gravitational acceleration, and θ is the inclination angle of the inclined plane. This achieves a direct proportional adjustment between the braking force and the additional force caused by the slope, effectively pre-compensating for the tendency of the car to slide downhill or assist uphill. Through this compensation, the braking system ensures that the scissor lift's initial deceleration feel and efficiency are consistent regardless of whether it is unloaded, heavily loaded, or operating on an uphill or downhill slope, greatly improving the predictability and comfort of operation. It also lays a precise initial condition for subsequent braking stages: by providing a braking force that is precisely matched to the total mechanical energy in the first stage (S301), the scissor lift can smoothly transition to a low-speed state with an optimal and controlled deceleration rate. This creates stable and ideal hydraulic system and initial speed conditions for the subsequent S302 (precise braking using counter-hydraulic pressure) and S303 (adaptive shutdown) stages, avoiding subsequent control pressure fluctuations or adjustment difficulties caused by improper initial braking force settings, and ensuring the overall synergy and final effect of the three-stage braking strategy. By integrating real-time sensor data, the physical model of the scissor lift, and the control execution strategy, this system demonstrates a model-based systematic control approach. This signifies that the system's control logic has evolved from a "perception-response" mode that relies on empirical rules to a higher level of "perception-prediction-decision" based on physical principles, thereby enhancing the technical level and intelligence of the entire braking system.

[0041] In this embodiment, the controller outputs instructions to the motor driver to maintain the enable signal and adjusts the throttle signal to the calculated target duty cycle value, thereby controlling the oil pump motor to enter the specified operating condition. The controller outputs the calculated target duty cycle value directly to the motor driver as an instruction, ensuring that the optimal control quantity obtained through complex algorithm optimization is accurately and error-free delivered to the execution end. Maintaining the enable signal ensures that the motor driver is in a controlled active state, preparing for receiving and executing new throttle instructions, avoiding interruptions or delays in instruction transmission, and ensuring the integrity of the control link. By precisely adjusting the throttle signal to the target duty cycle, the controller can directly and linearly control the speed and torque output of the oil pump motor, enabling the oil pump motor to quickly enter and stabilize at the working condition specified by the algorithm. This allows the hydraulic system to instantly generate counteracting oil pressure that precisely matches the current kinetic and potential energy of the scissor lift. This rapid and precise response is a direct guarantee for achieving smooth and efficient braking during the deceleration phase. Receiving instructions calculated by the decision algorithm and driving the oil pump motor to produce corresponding physical actions (outputting hydraulic oil with specific flow and pressure), the controller ultimately regulates the speed of the controlled scissor lift.

[0042] In this embodiment, step S302 specifically involves: due to the inertia of the scissor lift itself and the characteristics of hydraulic oil drive, the hydraulic oil pressure delivered by the high-speed rotation of the motor is much higher than that delivered by the low-speed rotation of the motor. The two oil lines counteract each other, thereby achieving a deceleration effect. At this time, the scissor lift will come to a stop. Deceleration is achieved by utilizing the counteracting of two hydraulic oil lines with different pressures within the hydraulic system. By controlling the speed of the oil pump motor to generate a pressure difference, the kinetic energy of the vehicle's forward movement is directly converted into the internal energy (heat energy) of the hydraulic system through turbulence, friction, and compression within the hydraulic oil. This avoids the use of traditional friction brakes, fundamentally eliminating component wear, thermal degradation, and maintenance / replacement problems caused by mechanical friction, and significantly improving the reliability and service life of the system. Unlike the jerky feeling produced by traditional braking systems, the counter-impact and pressure balancing of hydraulic oil is a relatively gentle fluid process. The resulting braking force is not an instantaneous rigid impact, but a continuous and smoothly varying force. This braking characteristic greatly suppresses shocks and platform sway during vehicle deceleration, providing operators with a smooth and comfortable braking experience, while also protecting the safety of precision instruments or cargo on the platform. The braking force originates directly from the hydraulic oil pressure difference precisely controlled by the motor speed. Because the electronic control system has an extremely fast response speed to the motor speed, the braking force generated by this method can closely follow the controller's commands, achieving precise and rapid adjustment of braking intensity. This high responsiveness provides the physical basis for implementing complex optimal control algorithms (such as adaptive control based on load and slope), ensuring that the control strategy can be accurately executed.

[0043] In this embodiment, the hydraulic system responds to the controller command and enters a hydraulic pressure counterbalancing state. This means that the hydraulic oil generated during high-speed travel and the low-pressure oil generated by the low-speed operation of the oil pump counterbalance each other in the oil circuit, rapidly consuming the vehicle's kinetic energy and achieving smooth deceleration. By utilizing the counterbalancing between the hydraulic oil and low-pressure oil within the hydraulic system to achieve deceleration, the kinetic energy of the scissor lift's forward movement is directly and efficiently converted into the internal energy (heat energy) of the hydraulic system and dissipated through the intense turbulence, friction, and compression within the hydraulic oil. This avoids traditional friction braking methods, fundamentally eliminating component wear, performance degradation, and the resulting maintenance requirements caused by mechanical friction, significantly improving the reliability, durability, and maintenance-free nature of the braking system. Unlike the rigid, step-like braking force generated by traditional friction braking, the hydraulic oil counterbalancing is a fluid pressure balancing process. The resulting braking force is not an instantaneous impact but a force that changes continuously and smoothly with the pressure difference. This inherent compliant characteristic greatly suppresses the impact, jerking, and platform sway during deceleration, providing the operator with superior stability and comfort, while also ensuring the safety of goods or precision operations on the platform. The braking force is directly generated by the oil pressure difference produced by the precise adjustment of the oil pump motor speed by the electronic control system. Because the response from the electronic control command to the change in motor speed is very rapid, the response delay of the braking system is extremely low, and the braking force can closely and linearly follow the controller's calculation command. This rapid execution is the key physical basis for realizing the aforementioned adaptive control algorithm (such as duty cycle adjustment based on load and slope), ensuring that advanced control strategies can be accurately and without distortion converted into actual braking effects.

[0044] In this embodiment, step S303 specifically involves: waiting for the hydraulic oil delivered during high-speed rotation to return, and then stabilizing the hydraulic oil delivered during low-speed rotation of the motor. The scissor lift resumes slow movement or stops. At this time, the solenoid valve is closed to cut off the enable and throttle signals, and the scissor lift stops steadily. Choosing the optimal locking timing, the controller does not immediately shut down the system after the scissor lift's speed drops to zero. Instead, it intelligently waits for the internal state of the hydraulic system to reach equilibrium, specifically, the high-speed oil flow completes its return and the low-speed oil flow stabilizes. This waiting process ensures that the residual pressure fluctuations and impact energy in the hydraulic circuit have been fully released and absorbed when the final shutdown operation is performed. At this point, closing the solenoid valve and cutting off the signal prevents the scissor lift from experiencing any jerking or slight slippage due to sudden changes in oil pressure, achieving stable stopping under various working conditions and eliminating safety hazards. By performing the shutdown operation only after the energy inside the hydraulic system reaches equilibrium, the final locking action is completed under near-static or quasi-static conditions with zero impact and zero disturbance. This avoids the hydraulic shock and mechanical vibration that may occur in traditional systems due to sudden valve closure, resulting in an exceptionally smooth stop for the scissor lift and improving operational comfort and quality. Step S303 is the final closed loop of the kinetic energy dissipation process. It confirms that the preceding stages (S301 deceleration, S302 hydraulic counter-pressure) have effectively dissipated most of the kinetic energy of the scissor lift, and the system has smoothly transitioned from the dynamic braking stage to the static holding stage. At this point, the shutdown operation locks the scissor lift into a smooth stop by cutting off the oil circuit and power signal. Choosing to shut off the solenoid valve after the oil pressure stabilizes avoids performing the valve closing action when the pressure is high or fluctuates drastically. This effectively reduces the damage of hydraulic shock to the solenoid valve and other hydraulic components, lowers the system failure rate, and extends the service life of the entire hydraulic system.

[0045] In this embodiment, the controller continuously monitors the pressure change rate and / or pressure difference of the main oil circuit; it determines whether the hydraulic system pressure has stabilized, i.e., whether the pressure fluctuation is below a preset threshold; if not, it returns to step S301 and continues to maintain the current output state; if yes, the hydraulic system pressure has stabilized, indicating that the scissor lift has come to a stop and the hydraulic shock has been effectively absorbed, and the controller immediately issues a final stop command: closing the forward solenoid valve or the reverse solenoid valve, completely cutting off the oil pump motor enable and throttle signal. By continuously monitoring the pressure change rate and / or pressure difference of the main oil circuit, the controller, for the first time, uses the dynamic response characteristics of the hydraulic system as the basis for judging the braking process, enabling the control logic to leap from relying on fixed timing or simple speed judgment to intelligent decision-making based on the actual physical state of the system (oil pressure stability), and can directly and sensitively perceive the energy fluctuation and balance process in the hydraulic circuit, thereby making the control choice that best suits the current actual situation. Using pressure fluctuations below a preset threshold as the sole condition for executing the final shutdown command ensures that the controller only locks up when the hydraulic shock has been completely absorbed and the energy within the hydraulic system has reached equilibrium. This eliminates jerking, swaying, or slight slippage of the scissor lift caused by premature shutdown (before the oil pressure stabilizes), and also avoids energy waste that may result from delayed shutdown. The introduced pressure monitoring and judgment mechanism perfectly complements the aforementioned open-loop feedforward control (S301 calculates the duty cycle based on load and slope). The "monitoring-judgment-loop / execution" logic constitutes a closed-loop feedback control, which can proactively correct any deviations that may exist in the preceding open-loop control or adapt to the performance differences of different hydraulic components. This ensures the robustness and consistency of the final effect of the entire three-stage braking strategy, giving the system a stronger fault tolerance to external disturbances and changes in internal parameters. If not, the loop judgment logic returns to step S301, enabling the system to dynamically maintain the current optimal braking output state until the condition is met. This ensures braking efficiency and avoids ineffective energy consumption. At the same time, the operation of closing the valve only after the oil pressure stabilizes effectively avoids hydraulic shock caused by switching the solenoid valve under high pressure or drastic pressure fluctuations, significantly reducing damage to valves and other hydraulic components and extending the service life of the system.

[0046] In this embodiment, in step 303, if pressure stabilization is not detected within a predetermined time, it is determined to be an abnormal situation, and the safety redundancy mechanism is automatically triggered, directly activating the mechanical brake or the highest priority braking command to ensure safety. By setting a predetermined time, the controller can proactively identify abnormal operating conditions that may occur in the hydraulic braking system, such as hydraulic leakage, sensor failure, controller calculation deviation, or actuator failure, which may cause the pressure to fail to stabilize as expected. This timeout judgment mechanism enables the system to have fault self-diagnosis capabilities, allowing it to promptly detect potential risks rather than waiting indefinitely or making incorrect judgments. As the final safety barrier of the entire electro-hydraulic braking control strategy, the core effect of the safety redundancy mechanism is that when the main braking system (wear-free braking based on hydraulic counter-pressure) fails to complete the braking task as expected, it can seamlessly and automatically switch to a backup, more reliable braking mode, forming a multi-layered safety architecture composed of the main braking system and the redundant backup system. This ensures that the braking safety performance of the entire vehicle will not be lost under any single fault condition, greatly improving the functional safety level of the system. By directly activating the mechanical brake or the highest priority braking command, bypassing potentially failing electro-hydraulic control circuits, the system executes the stopping action in the most direct and reliable manner. This ensures that even under the most unfavorable fault conditions, the vehicle can ultimately be reliably stopped, completely eliminating the risk of safety accidents caused by the failure of the main system and meeting the extreme safety requirements of aerial work equipment. The existence of redundancy mechanisms constitutes a safety guarantee, allowing the main intelligent braking system to be more aggressive in performance optimization, because even if the optimization algorithm fails under extreme boundary conditions, there is a reliable backup plan.

[0047] The scissor lift aerial work platform travel braking control system of this embodiment is used to implement the aforementioned scissor lift aerial work platform travel braking control method. It includes a controller, tilt sensor, pressure sensor, motor driver, and handle. The controller is electrically connected to the tilt sensor, pressure sensor, motor driver, and handle. By integrating the tilt sensor and pressure sensor, the system provides the controller with the ability to directly and in real-time measure the two key operating parameters: slope angle (θ) and load (m). This replaces the traditional system's reliance on indirect estimation or default values, providing an accurate data input source for subsequent algorithm-based precise calculations, facilitating precise matching and adaptive adjustment. The electrical connections between the controller and the sensors, driver, and handle construct a complete closed-loop control system. The execution channels are: handle (operation command), controller (calculation decision), motor driver (power drive), and oil pump motor (execution); the feedback channels are: tilt / pressure sensor (status perception) and controller (information fusion and judgment). This enables the system to acquire status information in real-time and adjust output commands accordingly, providing the physical carrier and architectural guarantee for implementing all adaptive control strategies (such as calculating duty cycle, judging oil pressure stability, and triggering redundancy mechanisms). By using the controller as the core processing unit of the system and centrally interconnecting it with various sensors and actuators, the components are no longer isolated entities but rather a highly integrated and uniformly managed whole. The controller can comprehensively process the operating intentions from the handle, the environmental load information from the sensors, and coordinate the output of the motor driver, thereby achieving centralized and systematic optimization management of the entire braking process. This is the core hardware platform for realizing the three-level cooperative braking strategy. The system architecture is a standard and flexible modular design, with the controller at its core, connecting various sensors and actuators through standard interfaces, facilitating functional upgrades and expansions. At the same time, centralized control also facilitates system self-diagnosis and unified safety management, laying the foundation for the overall reliability of the system.

[0048] like Figure 4 As shown, the core of this system's operating principle lies in the ECU's (Electronic Control Unit) fusion processing and coordinated control of multi-source information. Specifically, the control process involves: the handle signal (the operator's execution signal) and signals from the tilt sensor and pressure sensor (real-time operating conditions) are synchronously input into the ECU. Based on a built-in algorithm (e.g., D=15%+0.1m+0.05·tanθ), the ECU makes a decision and outputs two parallel control commands: one to the motor driver, precisely adjusting the oil pump motor speed to control the hydraulic oil flow and pressure; the other precisely controls the opening, closing, and direction of the hydraulic valve group to distribute the oil flow. Ultimately, through the synchronous and precise adjustment of the hydraulic power source and flow distribution mechanism via electronic control commands, the actuators are jointly driven to move, thereby achieving intelligent, stable, and adaptive control of the entire system's operating state and braking process.

[0049] In implementation, a method for controlling the travel braking of a scissor lift aerial work platform is provided, such as... Figure 1 As shown, it includes the following steps:

[0050] 1. When the system detects that the enable button on the control handle has been reset or the physical position of the handle has returned to the neutral position, it determines that the user has initiated a braking request and triggers the braking control sequence.

[0051] 2. The electronic control unit (ECU) reads system status parameters in real time, mainly including the current slope angle θ measured by the tilt sensor, and the current platform load m obtained by the pressure sensor or load calculation module.

[0052] 3. Based on the read slope and load information, the ECU inputs the preset algorithm model D=15%+0.1m+0.05·tanθ to dynamically calculate the optimal duty cycle of the oil pump motor. This model ensures a precise match between braking force and vehicle kinetic energy (positively correlated with load) and potential energy (positively correlated with slope).

[0053] 4. The ECU outputs a command to the motor driver to maintain the enable signal and adjusts the throttle signal to the calculated target duty cycle value, controlling the oil pump motor to enter the specified operating condition.

[0054] 5. The hydraulic system responds to the command and enters the critical "hydraulic pressure counter-current" state. That is, the hydraulic oil generated during high-speed travel and the low-pressure oil generated by the oil pump during low-speed operation counter-current in the oil circuit, rapidly consuming the vehicle's kinetic energy and achieving smooth deceleration.

[0055] 6. The system continuously monitors the pressure change rate or pressure difference of the main oil circuit.

[0056] 7. Determine whether the system pressure has stabilized (i.e., whether the pressure fluctuation is below the preset threshold, such as ΔP < 0.5 MPa / s). If not, return to step 4 and continue to maintain the current output state.

[0057] 8. Once the pressure stabilizes, indicating that the vehicle has come to a stop and the hydraulic shock has been effectively absorbed, the ECU immediately issues the final stop command: closes the forward / reverse solenoid valve, completely cutting off the motor enable and throttle signal.

[0058] 9. The vehicle comes to a smooth, undisturbed stop.

[0059] like Figure 2 and Figure 3 As shown, this relates to the rapid braking of a scissor lift:

[0060] 1. The ECU continuously outputs an enable signal, and sets the throttle signal duty cycle to 15-25% (depending on the load of the scissor lift; the higher the scissor lift's own weight + load, the greater the inertia, and the higher the duty cycle should be set).

[0061] 2. The above process enables the scissor lift to switch from high speed to low speed. Due to the inertia of the scissor lift itself and the characteristics of hydraulic oil drive, the hydraulic oil pressure delivered by the motor at high speed is much higher than that delivered by the motor at low speed. The two oil lines counteract each other, thus achieving a deceleration effect. At this time, the scissor lift will stop and wait for the hydraulic oil delivered at high speed to return. After the hydraulic oil delivered by the motor at low speed stabilizes, the scissor lift will resume slow movement or stop. At this time, the solenoid valve is closed, cutting off the enable and throttle signals, and the scissor lift will come to a steady stop.

[0062] 3. Based on the input value of the tilt sensor collected during the braking process, determine the current slope of the scissor lift. When the slope is larger, the time described in (2) for waiting for the hydraulic oil circuit to stabilize before shutting off the solenoid valve and cutting off the enable and throttle signals needs to be reduced according to the increase of the slope value.

[0063] like Figure 1 As shown, the safety redundancy mechanism (dashed path) is as follows: If the system fails to detect pressure stability within a predetermined time, it is determined to be an abnormal situation and the safety redundancy mechanism is automatically triggered, directly activating the mechanical brake or the highest priority braking command to ensure safety.

[0064] In addition, such as Figure 4 As shown, a scissor lift aerial work platform travel braking control system is provided. The system consists of: an electronic control unit (ECU), a tilt sensor, a motor driver, and a control handle (PCU). Slope adaptive braking: automatically adjusts the braking force based on tilt sensor data; pre-pressurization braking: initiates hydraulic braking in advance after detecting the control handle reset signal.

[0065] Comparison of experimental data:

[0066] Experimental equipment: scissor lift aerial work platform, data acquisition system (pressure sensor, CAN analyzer), controller, laptop computer.

[0067] Comparison method: Traditional two-stage braking (direct pressure relief + mechanical shutdown, no active deceleration stage).

[0068] Experimental conditions:

[0069] Operating Condition A: On a flat road surface, under rated load, braking begins from the maximum speed.

[0070] Operating Condition B: 15% slope (approximately 8.5°), under rated load, brake immediately after starting in the uphill direction.

[0071] Operating condition C: 15% gradient, under rated load, braking in the downhill direction.

[0072] Key metrics:

[0073] 1. Braking time (from triggering to complete stop);

[0074] 2. Braking distance;

[0075] 3. Equipment deceleration (G-value);

[0076] 4. Stopping stability (whether the final attitude is stable);

[0077] Comparison and analysis of experimental results and graphs:

[0078] The following are simulated experimental data curves and comparison tables, demonstrating the advantages of the three-level cooperative braking strategy of this invention.

[0079] The curve diagram for condition B (uphill braking) is as follows: Figure 5 As shown:

[0080] Curve analysis:

[0081] Traditional braking method: After the braking command is issued, the motor speed drops sharply, causing the vehicle to accelerate downhill under the action of gravity. There is a small "upward surge" in speed. Then the valve is immediately shut off, generating an extremely high inertial impact and deceleration peak, causing the equipment to "nod" and shake, and finally stop.

[0082] This invention's three-level coordinated braking strategy:

[0083] During the deceleration phase (t0-t1): the motor first reverses the drag, and the speed begins to decrease steadily, effectively offsetting the downward acceleration.

[0084] Depressurization phase (t1-t2): With the speed under control, the hydraulic system smoothly depressurizes, providing a smooth, linear deceleration. The pressure curve has no sharp peaks.

[0085] Shutdown phase (t2-t3): As the speed approaches zero, the mechanical brakes lock silently, completing the final braking. The entire process is smooth and seamless.

[0086] Table 1 shows a comparison of experimental data between traditional braking methods and the three-stage cooperative braking strategy of this invention:

[0087] Table 1. Comparison Table of Experimental Data

[0088]

[0089] Based on the above experimental data, graphs, and comparative analysis, a clear conclusion can be drawn:

[0090] 1. Enhanced safety: The three-level coordinated braking strategy of this invention completely eliminates the "rollback" phenomenon when braking on slopes using traditional methods, and significantly reduces the impact on the hydraulic system, thereby improving system reliability.

[0091] 2. Improved stability: By prioritizing motor braking, the abrupt intervention of hydraulic and mechanical systems is avoided, resulting in a smooth deceleration curve, which improves operator comfort and the stability of the work platform.

[0092] 3. Improved reliability: The significantly reduced hydraulic shock peak means that the lifespan of hydraulic lines, joints and components is extended, reducing maintenance costs.

[0093] 4. Intelligence: This strategy relies entirely on real-time collected data (speed, gradient) for decision-making, achieving a leap from "fixed logic braking" to "adaptive intelligent braking".

[0094] Matters not covered in this invention are common knowledge.

[0095] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

[0097] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A scissor aerial work platform travel brake control method, characterized in that, The method comprises the following steps: S100, the operation handle enables the key to reset and trigger the brake request, realize the initialization and triggering of the brake control sequence; S200, monitor the state of the scissor lift truck and collect the slope and load information, realize the synchronous acquisition of the external environment and the internal load state by calling the data of the inclination sensor and the pressure sensor in real time; S300, for the scissor lift truck fast brake, based on the real-time collected data, a three-level cooperative braking strategy of speed reduction, pressure relief and shutdown is adopted, the switching time sequence between each level is adaptively adjusted based on the real-time collected slope information, the braking process and the dynamic load and terrain conditions are accurately matched, so that the braking efficiency and the terminal stopping stability are considered under the premise of no mechanical wear; Step S300, specifically comprising the following steps: S301, after the ECU receives the brake signal of the PCU, the ECU first continuously outputs the enable signal to make the controller continue to control the walking motor to reduce speed, sets the throttle signal duty ratio to 15-25%, and makes the scissor lift truck quickly change from high speed to low speed, so as to eliminate the main inertia, realize smooth initial stage speed reduction, and reduce hydraulic impact; S302, based on the characteristics of the hydraulic system, the speed difference of the oil pump motor is controlled to generate counteracting oil pressure to achieve the effect of speed reduction, and then the scissor lift truck is stopped; Step S302, specifically: due to the inertia of the scissor lift truck itself and the characteristics of the hydraulic oil drive, the hydraulic oil pressure sent by the high-speed rotating motor is much higher than that sent by the low-speed rotating motor, and the two oil paths collide to achieve the effect of speed reduction, at this time the scissor lift truck will stop; S303, after the oil pressure of the hydraulic oil path is stable, the control signal and the hydraulic oil path are cut off to ensure that the scissor lift truck stops smoothly; S400, the scissor lift truck stops and tends to be stable.

2. The scissor aerial work platform travel brake control method according to claim 1, characterized in that, Step S303, specifically: S3031, collect the input value of the inclination sensor to determine the slope of the current scissor lift truck; S3032, the greater the slope, the smaller the time to cut off the control signal and the hydraulic oil path when the oil pressure of the hydraulic oil path is stable; the smaller the slope, the greater the time to cut off the control signal and the hydraulic oil path when the oil pressure of the hydraulic oil path is stable.

3. The scissor aerial work platform travel brake control method of claim 1, wherein, The throttle signal duty ratio setting in step S301 is adjusted according to the load of the scissor lift truck; the higher the self weight and load of the scissor lift truck, the greater the inertia, and the greater the duty ratio setting, and vice versa.

4. The scissor aerial work platform travel brake control method of claim 1, wherein, Step S301, specifically: The controller reads the state parameters in real time, including the current slope angle θ measured by the inclination sensor, and the current load m of the platform obtained by the pressure sensor or load calculation module; The controller substitutes the read slope and load information into the preset algorithm model: D=15%+0.1m+0.05·tanθ, The optimal oil pump motor duty ratio required at present is dynamically calculated to ensure the accurate matching of braking force and vehicle kinetic energy and potential energy, and the vehicle kinetic energy is positively correlated with the load, and the potential energy is positively correlated with the slope.

5. The scissor aerial work platform travel brake control method according to claim 4, characterized in that, The controller outputs the instruction to the motor driver, maintains the enable signal, and adjusts the throttle signal to the target duty ratio value calculated, and controls the oil pump motor to enter the specified working condition.

6. The scissor aerial work platform travel brake control method of claim 1, wherein, The hydraulic system responds to the controller's instructions to enter the oil pressure counter-attack state, that is, the hydraulic oil generated during high-speed walking collides with the low-pressure oil generated by the low-speed operation of the oil pump in the oil circuit, rapidly consuming the vehicle's kinetic energy, and achieving smooth deceleration.

7. The scissor aerial work platform travel brake control method according to claim 1, wherein, Step S303, specifically: After waiting for the hydraulic oil sent during high-speed rotation to return, the hydraulic oil sent during low-speed rotation of the motor tends to be stable, the forklift resumes slow walking or stops, at which point the solenoid valve is closed, the enable and throttle signals are cut off, and the forklift stops steadily.

8. The scissor aerial work platform travel brake control method according to claim 7, characterized in that, The controller continuously monitors the pressure change rate and / or pressure difference of the main oil circuit; Determine whether the hydraulic system pressure has stabilized, that is, whether the pressure fluctuation is below the preset threshold; if not, return to step S301 and continue to maintain the current output state; If yes, the hydraulic system pressure has stabilized, indicating that the forklift has come to a stop and the hydraulic impact has been effectively absorbed, and the controller immediately issues a final stop command: Close the forward or reverse solenoid valve and completely cut off the oil pump motor enable and throttle signals.

9. The scissor aerial work platform travel brake control method according to any one of claims 1 to 8, characterized in that, In step 303, if the pressure is not stabilized within a predetermined time, it is determined to be an abnormal situation, and the safety redundancy mechanism is automatically triggered to directly start the mechanical brake or the highest priority brake command to ensure safety.

10. A scissor-type aerial work platform travel brake control system for implementing the scissor-type aerial work platform travel brake control method of any one of claims 1 to 9, characterized by, The controller, the inclination sensor, the pressure sensor, the motor driver, and the handle are included. The controller is electrically connected to the inclination sensor, the pressure sensor, the motor driver, and the handle, respectively.

Images