1、 附录： 英文原材料 How Car Suspensions Work Without an intervening structure, all of wheels vertical energy is transferred to the frame, which moves in the same direction. In such a situation, the wheels can lose contact with the road completely. Then, under the downward force of gravity, the wheels can sla
2、m back into the road surface. What you need is a system that will absorb the energy of the vertically accelerated wheel, allowing the frame and body to ride undisturbed while the wheels follow bumps in the road. The study of the forces at work on a moving car is called vehicle dynamics, and you need
3、 to understand some of these concepts in order to appreciate why a suspension is necessary in the first place. Most automobile engineers consider the dynamics of a moving car from two perspectives: Ride - a cars ability to smooth out a bumpy road Handling - a cars ability to safely accelerate, brake
4、 and corner These two characteristics can be further described in three important principles - road isolation, road holding and cornering. The table below describes these principles and how engineers attempt to solve the challenges unique to each. Principle Definition Goal Solution Road Isolation Th
5、e vehicles ability to absorb or isolate road shock from the passenger compartment Allow the vehicle body to ride undisturbed while traveling over rough roads. Absorb energy from road bumps and dissipate it without causing undue oscillation in the vehicle. Road Holding The degree to which a car maint
6、ains contact with the road surface in various types of directional changes and in a straight line (Example: The weight of a car will shift from the rear tires to the front tires during braking. Because the nose of the car dips Keep the tires in contact with the ground, because it is the friction bet
7、ween the tires and the road that affects a vehicles Minimize the transfer of vehicle weight from side to side and front to back, as this transfer of weight reduces the tires toward the road, this type of motion is known as dive. The opposite effect squat occurs during acceleration, which shifts the
8、weight of the car from the front tires to the back.) ability to steer, brake and accelerate. grip on the road. Cornering The ability of a vehicle to travel a curved path Minimize body roll, which occurs as centrifugal force pushes outward on a cars center of gravity while cornering, raising one side
9、 of the vehicle and lowering the opposite side. Transfer the weight of the car during cornering from the high side of the vehicle to the low side. A cars suspension, with its various components, provides all of the solutions described. Lets look at the parts of a typical suspension, working from the
10、 bigger picture of the chassis down to the individual components that make up the suspension proper. Car Suspension Parts The suspension of a car is actually part of the chassis, which comprises all of the important systems located beneath the cars body. Suspension Types: Rear Dependent Rear Suspens
11、ions If a solid axle connects the rear wheels of a car, then the suspension is usually quite simple - based either on a leaf spring or a coil spring. In the former design, the leaf springs clamp directly to the drive axle. The ends of the leaf springs attach directly to the frame, and the shock absorber is attached at the clamp that holds the
