Wood loader is mainly composed of engine, transmission train, steering system, braking system, walking device, frame and working device (see figure). The frame of the wheel loader is hinged by the front and rear parts, and the working mechanism is installed on the front frame, and the cab and engine are installed on the rear frame. The engine generally adopts diesel engine. Wheeled powertrain most of the use of hydraulic mechanical, also useful static pressure transmission. The gear drive of the engine torque converter drives the working, steering and variable speed oil pumps. The pressure oil is respectively led to the hydraulic steering system composed of the hydraulic steering gear and the steering cylinder through the tubing in the overhead cavity of the front car, as well as the hydraulic system of the working parts.
The hydraulic steering system consists of an upper distribution valve and a lower planetary rotor pump. When the steering wheel is operated, the rotor pump pumps out a certain amount of oil into the steering cylinder, which pushes the pistons to move and causes the wheels to turn. The caterpillar driveline feeds the engine power to the rear axle through the clutch, transmission and transmission shaft to rotate the driving wheels and make the caterpillar run. Modern crawler models are also equipped with a hydraulic torque converter and a power shift transmission to improve performance.
The steering method of the crawler loader is to brake the crawler on one side, so that the whole machine turns around the side. The hydraulic system of the working device, including lifting the heavy arm, turning the rocker arm and connecting rod, and turning the jaw jaw (gripper), etc., is fully controlled in the cockpit.