Wheel excavator is a kind of multifunctional and self moving construction machinery, which is mainly used in municipal engineering construction and emergency construction. Compared with crawler excavator, the structure of upper mechanism and working device of wheel excavator is similar, but the structure of chassis system is completely different. The driving and steering of wheeled excavator is realized by deflecting the steering wheel, while the driving and steering of crawler excavator is realized by the rotation of the left and right crawlers in the chassis system.
In the excavation condition, the tires of wheeled excavators can not stably support the excavation operation, so the chassis system of wheeled excavators is generally equipped with bulldozer or outrigger mechanism. In the excavation condition, the bulldozer or outrigger is used to support to the ground to enhance the stability of the whole machine.
The wheel excavator should not only ensure the reasonable distribution of the center of the whole machine when driving, but also ensure the balance of the whole machine when digging. Full hydraulic steering system is widely used in wheel excavators. Its function is to control the driving direction of the machine. This kind of full hydraulic steering system has the characteristics of light operation, quick response and reliable steering. Due to the different driving and digging states of wheeled excavators, the upper mechanism can not rotate in some narrow areas, so it is necessary to drive and steer behind the machine. At this time, the steering direction of the machine is opposite to that of the steering wheel, which will make it difficult for drivers to judge and operate the direction.