SHOCK ABSORBER


Need of shock absorber
Soft spring gives more vibration to the vehicle body and chassis, and hard spring will not give cushioning under small loads thus causing in comfort to the occupants. To avoid this we can use shock absorber.

PRINCIPLE OF SHOCK ABSORBER
It works on the principle of fluid friction when fluid under pressure is allowed to flow through small holes. Which cause fluid friction, friction is developed because whole of the fluid cannot pass through the holes suddenly and it will oppose the flow of fluid.
Actually, the shock the absorber does not absorb the shocks but it provides damping effect caused by shock. So it also called damper.

WORKING OF SHOCK ABSORBER


When the vehicle comes across a bump, the two eyes come closer to each other. So, the fluid in                                                  the lower chamber of cylinder is under pressure. As the fluid is incompressible, it pushes the bump valve upward and fluid start to flow towards upper chamber. As the hole is small, it generates fluid friction which provides damping. Also the volume of upper chamber is lass due to the volume of rod, some of the fluid flows to the tube by opening the one way valve at the bottom of cylinder.
During the reverse stroke, the piston is pushed up towards the cylinder head. Now the fluid in upper chamber is under pressure, and it opens the rebound valve whereas the bump valve is closed.

FUNCTION OF SHOCK ABSORBER


1.    It provides the damping effect to sudden shock provided due to road roughness.
2.    It helps the suspension system to road tyre contact.
3.    It controls the rolling of the vehicle while taking turn.
4.    It provides comfort to the occupants of the vehicles.