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Car Suspension - Shock Absorber

Aug 02, 20243 min read

Car suspensions take advantage of the friction between the tires and the road to allow the car to steer properly. They are necessary to ensure the stability of the car when steering; without them, it would be challenging for cars to travel safely on a road with irregularities (which is always the case).

Functions of car suspensions:

  1. Road Isolation: allows cars to ride undisturbed by absorbing energy from road bumps.
  2. Road holding: keeps the tires in contact with the road’s surface by minimizing the transfer of the car’s weight—the weight transfer lessens the tire’s grip on the road.
  3. Cornering: allows the car to safely travel a curved path by minimizing body roll and transferring the weight of the car when it corners from the high side to the low side.

Car suspensions are part of the chassis, the crucial systems below the car’s body. This chassis is divided into the following parts:

  1. Frame - the structure that supports the car’s body, and is supported by the suspension
  2. Suspension system - the setup that supports weight, absorbs the shock, and keeps the tires in contact with the road.
  3. Steering system
  4. Tires and wheels

Car suspensions have three fundamental components: springs, dampers, and sway bars. Springs are used for absorbing energy, while the dampers or shock absorbers are used to dissipate the absorbed energy. Sway bars, on the other hand, provide additional stability and reduces sway by transferring movement to the wheel when the other wheel moves up and down.

What Are Shock Absorbers

Without a dampening structure, like shock absorbers, cars would become very bouncy since the springs in the suspension system will uncontrollably release the energy absorbed. The process of releasing involves the spring continuously bouncing until all the energy absorbed is gone. For this reason, shock absorbers were made to dampen the unwanted spring motion.

Shock absorbers obtains kinetic energy from the spring’s vibratory motion, then converts it into heat energy for the hydraulic fluid to dissipate. In other words, once a car encounters a bump, the spring bounces and absorbs energy. Because shock absorbers are simply just oil pumps, the hydraulic fluid dissipates the heat energy by forcing itself into the holes of the piston. The small amount of fluid passing through, due to the small orifices, ensures that the piston is slowed; thus, it also minimizing the spring and suspension movement.

Shock absorbers are important because they keep your tires in contact with the surface of the road. Without them, you risk being unable to drive, steer, and brake whenever the tires lose contact with the ground.

Sample Images

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CAD Examples/References

Sources

  1. William Harris, Kristen Hall-Geisler, HowStuffWorks, “How Car Suspensions Work” - Accessed on 2024-08-02
  2. Monroe, “Shock Absorbers Explained” - Accessed on 2024-08-02

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