1. Shock absorption: the body and the car are flexibly connected to one piece. When the car is driving, the axle and frame are flexibly connected through the lower arm to slow down the impact caused by the ground during the driving of the vehicle and ensure the comfort of the seat.

2, guiding effect: attenuation due to the vibration caused by the elastic system, transfer from the longitudinal, vertical or lateral reaction and its torque, so that the wheel according to a certain track compared to the body movement, play a guiding role.

The guide arm is installed between the axle and the guide arm bracket, and the guide arm is formed in one body, including: the straight part is installed on the axle; The bending part, one end of the bending part is connected with the flat part; The ear curl is located at the other end of the bending part, and the ear curl forms a crimping hole for mounting the guide arm bracket; Wherein, the curved part has a bending tendency to tilt upward from the straight part to form a height drop between the axis of the curly ear hole and the upper surface of the straight part.