Leaf Spring

Leaf Spring

Leaf springs are made from flat strips of springs steel. Each strip is called a leaf. Several strips are placed one on the other. They are jointed together by clamps (rebound clips) and a central bolt. The length of each leaf decreases so that the spring assembly acts as a flexible beam and is of uniform strength. To longest strip is called main leaf spring or master leaf spring. The ends of the master spring are formed into loops called spring eyes. One end of the spring is attached with the frame through a spring bolt passing through the spring eye.

The other end is secured through a shackle as shown in fig

The shackle helps in accommodating the change in length of the spring. When the wheel encounters a bump, the spring expands the increase in length takes place with is accommodated by the shackle. Similarly the reverse process of contraction is accommodated. Bronze bushes are generally fitted into the spring eyes and through the bush, bolt passes. In some cases rubber is used instead of bushes. The rubber bushes are quiet in operation and require no lubrication.

The leaf spring may be placed on the axle and kept in position by a U-Bolt. The U-clamp in this case does not take any load but simply keeps the springs in position. In light duty vehicle, the spring is placed below the axle and the load is transmitted through the U-bolts of the axle. Another method of attaching the leaf spring to the frame and rear Axle is shown in fig.

References

1. Automobile Engineering (Vol. 1 & 2)            -           K.M.Guptha
2. Automotive Mechanics                                   -           Joseph Heitner
3. Automobile Engineering                                 -           Harbans Singh Reyd
4. Automotive Mechanics                                   -           William H. Course