Linkage logic and troubleshooting ideas of electrical control system and hydraulic drive system of work bucket of aerial work platform

A complex electrical control system is integrated in the working bucket (platform) of a modern aerial work platform. It and the hydraulic drive system of the chassis jointly realize various action instructions of the operator through electro-hydraulic linkage logic.Understanding this linkage logic and mastering basic troubleshooting ideas are essential to ensure the continuity and safety of operations.Usually, the operation panel in the work bucket is provided with a direction control handle (or button), an engine throttle switch, an emergency stop button, etc.The operator's instructions (such as ”boom rise") are transmitted to the chassis controller in the form of electrical signals through the central rotary joint.After the controller analyzes the signal, it sends a control current to the corresponding hydraulic valve group solenoid valve, drives the valve core to move, and causes the hydraulic oil to flow into the corresponding cylinder or motor to complete the action.At the same time, the controller will also receive feedback signals from each sensor in real time (such as boom angle, length, platform load, chassis level), make logical judgments, and immediately cut off the corresponding actions or issue an alarm to achieve safe interlocking.

Typical linkage logic includes: boom action is only allowed if the chassis outriggers have been expanded and the frame is horizontal; after the boom extends to a certain range, the system will automatically limit the lifting height or rotation speed (torque limiting function) according to the real-time load; when the platform load exceeds the rated weight, the system will issue an alarm and prohibit all rising actions; two-way balance valve to ensure that the cylinder will not fall out of control due to pipeline rupture under load.

The basic idea of troubleshooting follows the principle of ”from simplicity to complexity, first electricity and then liquid, first safety and then action".In the event of a failure, first check whether it is improper operation, such as whether the emergency stop button is pressed, and whether the platform/ground operation selector switch is correct.Secondly, check the power supply, such as the battery voltage and whether the fuse is blown.Then observe whether the controller display or indicator light has a fault code prompt, which can help locate the general direction.When troubleshooting the electrical system, check whether the relevant sensor plug is loose and the circuit is damaged; check whether the solenoid valve coil is burned or voltage.When investigating the hydraulic system, listen to the hydraulic pump for abnormal noise, check whether the oil level is sufficient, whether the filter element is clogged, and whether the relevant oil cylinder or motor has internal leakage, causing the action to be slow or unable to maintain pressure.For some complex faults, such as unstable movement and jitter, it may be necessary to use a pressure gauge to detect the system pressure.Mastering systematic troubleshooting methods can help operators and maintenance personnel quickly locate problems, reduce downtime, and avoid secondary damage caused by blind disassembly. It is an important skill to ensure equipment attendance.