The power steering gear is actually a combination of a mechanical steering gear and a steering booster device. According to the different energy transfer medium, there are two types of power steering gear: pneumatic type and hydraulic type. Among them, the hydraulic power steering gear can be divided into integral type (mechanical steering gear, steering power cylinder and The three steering control valves are designed as one), semi-integrated (the mechanical steering gear and the steering control valve are designed together, and the steering power cylinder is independent) and the separate type (the mechanical steering gear is independent, the steering control valve and the steering power cylinder are designed separately) Design as one) three structural types.
It is worth noting that it is not suitable to use pneumatic power steering gear for trucks with extra heavy load, because the working pressure of the pneumatic system is low (generally not higher than 0.7MPa), and the size of its components will be too large when used on heavy vehicles. The working pressure of the hydraulic power steering gear can be as high as 10MPa or more, so the size of its components is very small. The hydraulic system works without noise, has a short working lag time, and can absorb the impact from uneven roads. Therefore, hydraulic power steering has been widely used in various types of automobiles.