08-12-2012, 06:21 PM
WHAT IS SPRING
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Springs are elastic bodies (generally metal) that can be twisted, pulled, or stretched by some force. They can return to their original shape when the force is released.
In other words it is also termed as a resilient member.
CLASSIFICATION OF SPRINGS
Helical springs:
Tension helical spring
Compression helical spring
Torsion spring
Spiral spring
TENSION HELICAL SPRING (OR) EXTENSION SPRING
It has some means of transferring the load from the support to the body by means of some arrangement.
It stretches apart to create load.
The gap between the successive coils is small.
The wire is coiled in a sequence that the turn is at right angles to the axis of the spring.
The spring is loaded along the axis.
By applying load the spring elongates in action
TORSION SPRING
It is also a form of helical spring, but it rotates about an axis to create load.
It releases the load in an arc around the axis.
Mainly used for torque transmission
The ends of the spring are attached to other application objects, so that if the object rotates around the center of the spring, it tends to push the spring to retrieve its normal position.
SPIRAL SPRING
It is made of a band of steel wrapped around itself a number of times to create a geometric shape.
Its inner end is attached to an arbor and outer end is attached to a retaining drum.
It has a few rotations and also contains a thicker band of steel.
It releases power when it unwinds.