Car Suspension Knowledge Introduction

- Jan 03, 2019-

The front and rear suspension system of the car includes two parts, a spring and a shock absorber. The structure is divided into the following forms: McPherson, A-arm (double crossbar), trailing arm, torsion beam and multi-link.

The McPherson suspension is mostly used for the front wheel. It is a kind of independent suspension, and it is a very simple structure. It is compact in layout, saves space, has small change in front wheel positioning, and has good driving stability. Therefore, most of the car front suspensions use this structure, the difference is mainly in the selection of materials and shock absorbers, spring adjustment. However, the MacPherson suspension also has the disadvantage that the wheel is easy to automatically turn when driving on uneven roads, so the driver must force the direction of the steering wheel. When subjected to severe impact, the shock absorber is easy to bend, thus affecting Steering performance.

The double A-arm suspension has two upper and lower rocker arms, and the lateral force is absorbed by both rocker arms at the same time, and the pillars only carry the weight of the vehicle body. Therefore, the lateral stiffness is large. Since the unequal length rocker arm (upper length and lower length) is used up and down, the wheel can automatically change the camber angle when moving up and down and reduce the wheel track variation to reduce tire wear. And it can also adapt to the road surface, the tire has a large grounding area and good grounding. However, due to the addition of an upper rocker arm, it is necessary to use a larger space.

The trailing arm suspension system is a suspension system designed for the rear wheel. The biggest advantage of the trailing arm suspension system is that the left and right wheels have a large space, and the camber angle of the body does not change. The shock absorber does not have bending stress, so the friction Small, good ride, when the brakes, in addition to the heavy head will sink, the rear wheel of the trailing arm will also sink to balance the body, but its shortcoming is that it can not provide accurate geometric control, but if the adjustment Properly, the effect can be achieved with the least cost and space, so today's cars use this type of rear suspension.

The torsion beam suspension is a semi-independent suspension method. The suspension structure is simple and the transmission force is reliable, but the two wheels will affect each other when subjected to shock and vibration. The fine vibration can be well filtered, and the reaction to the large pit is relatively stiff.

The multi-link suspension system is further divided into 5 links and 4 links. The multi-link rear suspension can realize the position of the caster back rake angle, greatly reducing the front-rear direction force from the road surface, thereby improving the smoothness and comfort during acceleration and braking, and also ensuring the stability of straight-line driving in the vehicle. When turning or braking, the 5-link rear suspension structure allows the rear wheel to form a positive front beam, which improves the vehicle's control performance and reduces understeer. The front suspension of many luxury cars also uses a 4-link front suspension that subtly separates the traction, braking and steering forces through kinematics while giving the vehicle steering control.

In summary, although multi-links have many innate advantages, it seems to be the way, but with so many points of force, it will be difficult to adjust, and there is no advantage in taking up space and cost, so we are buying a car. Don't worry too much about whether or not multi-links are used. If it is a Class A or below, the former McPherson, the rear towing arm is a very good match. For the B-level and above, each car manufacturer has different preferences. In principle, as long as the vehicle style is used. Coordination, we do not have to identify a suspension method, if the pursuit of performance, then you can go to the professional modification store to do deep adjustment.