Six systems of hydraulic excavator(1)

Transmission system

Single-bucket hydraulic excavator is widely used in construction, transportation, water conservancy construction, open-pit mining and modern military engineering, and is an indispensable main mechanical equipment in all kinds of earthwork construction. Fluid transmission includes the following three forms: 1, hydraulic transmission - by means of the pressure of the liquid to transfer power and movement of the transmission form; 2, hydraulic transmission - by means of the kinetic energy of the liquid to transfer power and motion transmission form; (such as hydraulic torque converter) 3, pneumatic transmission - transmission form of power and movement by means of the pressure energy of the gas.

Dynamic system

It can be seen from the appearance characteristic curve of diesel engine that the diesel engine is approximately constant torque regulation, and the change of its output power is manifested as the change of speed, but the output torque is basically unchanged.

Throttle opening increases (or decreases), the diesel engine output power increases (or decreases), because the output torque is basically unchanged, so the diesel engine speed also increases (or decreases), that is, different throttle opening corresponds to different diesel engine speed. It can be seen that the purpose of diesel engine control is to realize the adjustment of diesel engine speed by controlling the throttle opening. The control devices used in the diesel engine of hydraulic excavator include electronic power optimization system, automatic idle speed device, electronic governor, electronic throttle control system, etc.

Dynamic system

Dynamic system

Component system

The control of hydraulic pump is achieved by adjusting its variable swing Angle. According to the different control forms, it can be divided into three categories: power control system, flow control system and combined control system.

The power control system includes constant power control, total power control, pressure cut-off control and variable power control. The flow control system includes manual flow control, positive flow control, negative flow control, maximum flow two-stage control, load sensing control and electrical flow control, etc. Combined control system is a combination of power control and flow control, which is used most in hydraulic control machines.

Component system

Component system


Post time: Sep-17-2023