1. Definition
The frame is a frame structure spanning the front and rear axles of the car, commonly known as the girder, and is the base of the car. Generally, it consists of two longitudinal beams and several cross beams, and is supported on the wheels via the suspension device, the front axle and the rear axle. The frame must have sufficient strength and rigidity to withstand the load of the car and the impact from the wheels. The function of the frame is to support and connect the various assemblies of the car, so that each assembly maintains a relatively correct position, and bears various loads inside and outside the car.
2. Classification of
frames Frames are currently divided into peripheral frames, spine frames, trapezoidal frames and truss frames according to different structural forms.
1. Peripheral
frame The middle part of the frame is widened without beams, and its main parts are usually closed sections. Peripheral frames are used in passenger cars with large displacement due to low floor height, large passenger compartment volume, simple structure, low mass, and ease of manufacture.
2. Spine frame
A spine frame has only one longitudinal beam in the center that runs through the front and rear of the car. The cross-sectional shape of the stringer can be round tube or box.
The frame of the spine frame has small mass, high strength and high rigidity, and it can improve the passing ability of the car when used in conjunction with the independent suspension. The frame requires high manufacturing precision and difficult maintenance and repairs are its disadvantages.
3. Trapezoidal frame
It consists of two longitudinal beams and several beams. The cross-sectional shape of the longitudinal beam is trough-shaped, Z-shaped or box-shaped. Longitudinal beams can be made into curved, constant or variable sections in the horizontal plane or in the longitudinal plane.
The trapezoidal frame is widely used in commercial trucks and some passenger cars because of its high bending strength and fast and convenient installation of parts. It is rarely used in passenger cars.
4. Truss-type frame
The truss-type frame is welded by combining steel pipes. It has the characteristics of high rigidity and low mass, but it is difficult to manufacture and is mainly used in racing cars.
Note: This article was originally created by Auto Repair Collection – Guyun, if you need to reprint, please indicate the source!
