The working devices of an aerial work platform include outrigger mechanism, lifting mechanism, slewing mechanism, working platform, and leveling mechanism.
(1) Outrigger Mechanism
Currently, hydraulic outriggers are mostly used. The power extracted from the vehicle engine drives a hydraulic pump, and the hydraulic oil generated by the pump is supplied to the working cylinders of the hydraulic outriggers through a control valve, enabling the outriggers to extend and retract. Control levers are generally provided on both sides of the aerial work platform, allowing the four hydraulic outriggers (front, rear, left, and right) to extend or retract individually. Therefore, even on uneven or tilted ground, the vehicle body can be leveled for safe operation.
(2) Lifting Mechanism
This mechanism enables the lifting and lowering of the working platform.
Vertical lifting mechanisms can be classified into hydraulic transmission and mechanical transmission according to the transmission method, and into cross-scissor type and sleeve type according to their structural form. The cross-scissor type is a cross-arranged, hinged linkage frame structure. Changing the angle of the cross linkages achieves the lifting motion.
(3) Slewing Mechanism
A full-rotation slewing mechanism is usually used, and the forward and reverse directions can be selected according to the operational needs. Generally, a hydraulic motor drives a mechanical slewing device with a speed reduction function to rotate. The slewing part of the slewing mechanism and the working platform are both mounted on the slewing bearing, i.e., the turntable.
(4) Working Platform and Leveling Mechanism The end of the lifting mechanism connects to the working platform, which is a basic component used to carry personnel or equipment. To ensure the safety of workers and prevent equipment from falling, various countries have put forward clear requirements for the structure and performance of the working platform. These include the height of the platform railings, the platform width, the anti-slip surface of the platform, and the safety belts on the platform.
