1. Jasmeen Kaur Dhillon Asst.Proffesor Mechanical Department

2. Springs are the elastic members which distort under load and regain original shape when load is removed
Jasmeen Kaur Dhillon, C.T.I.E.M.T

3. To absorb shock or impact loading as in carriage springs
To Store energy as in clock springs
To apply force to and to control motion in
brakes and clutches
To measure force as in spring balance
Jasmeen Kaur Dhillon, C.T.I.E.M.T

4. Suspension Trampoline Mattress Stapler Pens Pogo Stick
Jasmeen Kaur Dhillon, C.T.I.E.M.T

5. Material used for spring are :-
High Carbon Steel(0.7 to 1.0%)
Medium Carbon Steel(0.3 to 0.59%)
Material used for corrosion resistance of spring are:-
Phosphor bronze
Titanium
Brass
Chrome Vanadium
Jasmeen Kaur Dhillon, C.T.I.E.M.T

6. The outside diameter is (OD), The inside diameter is (ID),
The above figure shows the notation used in referring to the characteristic diameters of helical compression springs.
The outside diameter is (OD),
The inside diameter is (ID),
The wire diameter is (Dw)
continue…….
Jasmeen Kaur Dhillon, C.T.I.E.M.T

7. In calculating the stress and deflection of a spring,
we use the mean diameter, Dm.
OD = Dm + Dw
ID = Dm – Dw
Jasmeen Kaur Dhillon, C.T.I.E.M.T

8. Nomenclature for springs:
Free length: The overall length of a spring in the unloaded position.
Solid Height: It is the length of a compression spring when under sufficient load to bring all coils into contact with adjacent coils
Pitch: The distance from centre to centre of the wire in adjacent active coils (recommended practice is to specify number of active coils rather than pitch).
Spring Rate: The change in load per unit deflection, generally given in pounds per inch or Newtons per millimetre.
Spring Index: The ratio of mean coil diameter (D) to wire diameter (d).
Deflection: The motion of spring ends or legs under the application or removal of an external load.
Endurance Limit: It is the maximum stress at which any given material will operate indefinitely without failure for a given minimum stress.
Closed Ends: They are the ends of compression springs where pitch of the end coils is reduced so that the end coils touch.
Active Coils: Those coils which are free to deflect under load.
Jasmeen Kaur Dhillon, C.T.I.E.M.T

9. Helical Springs Leaf Springs Torsion Springs Circular Springs
Closed Coil Helical Spring
Open Coiled Helical Springs
Tension Helical Springs
Compression Helical Springs
Leaf Springs
Full Elliptic
Semi Elliptic
Cantilever
Torsion Springs
Circular Springs
Belleville Springs
Flat Springs
cont……
Jasmeen Kaur Dhillon, C.T.I.E.M.T

10. Jasmeen Kaur Dhillon, C.T.I.E.M.T

11. Jasmeen Kaur Dhillon, C.T.I.E.M.T

12. Jasmeen Kaur Dhillon, C.T.I.E.M.T

13. 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
Jasmeen Kaur Dhillon, C.T.I.E.M.T

14. It compresses to support the load.
The gap between the successive coils is more as
compared to tension spring.
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 get compressed in
action
Jasmeen Kaur Dhillon, C.T.I.E.M.T

15. 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.
Jasmeen Kaur Dhillon, C.T.I.E.M.T

16. 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.
Jasmeen Kaur Dhillon, C.T.I.E.M.T

17. It is also called as a semi-elliptical spring, as it takes the
form of a slender arc shaped length of spring steel of
rectangular cross section.
The center of the arc provides the location for the
axle, while the tie holes are provided at either end for
attaching to the vehicle body.
Heavy vehicles, leaves are stacked one upon the other to
ensure rigidity and strength.
It provides dampness and springing function.
The shackle takes up the tendency of the leaf spring to
elongate when it gets compressed and by which the
spring becomes softer.
Jasmeen Kaur Dhillon, C.T.I.E.M.T

18. Jasmeen Kaur Dhillon, C.T.I.E.M.T

19. The Belleville spring has the shape of shallow conical disk with a central hole.
It is sometimes called Belleville washer because it’s appearance is similar to that of a flat washer.
A very high spring rate or spring force can be developed in a small axial space with such springs.
By varying the height of the cone relative to the thickness of the disk, the designer can obtain a variety of load – deflection charsacertics.
Jasmeen Kaur Dhillon, C.T.I.E.M.T

20. Jasmeen Kaur Dhillon, C.T.I.E.M.T

21. Jasmeen Kaur Dhillon, C.T.I.E.M.T

22. Jasmeen Kaur Dhillon, C.T.I.E.M.T

23. Jasmeen Kaur Dhillon, C.T.I.E.M.T