Spring is a type of mechanical device which show movement in upward or downward direction or a device which can store mechanical energy. When we apply specific amount of force is applied on it under elastic limit, it will come to its original position by pushing force and this pushing force is the energy released. This energy is store in it when external force is applied. Material of the spring must be non-magnetic, electricity conductivity and has high temperature working ability. Max temperature on which springs can work is up to 1100°F.
There are many types of springs used which are following
• Helical springs
• Conical and volute springs
• Leaf spring
• Disk springs
• Torsion bar
• Special purpose springs
Helical spring is said to be a spiral type spring which is coiled in the form of helix. There are further two types of helical springs depending upon the direction load and these springs are
Compression helical spring is a spring which compress after the load is applied. In the result, the length of the spring reduces and energy stores it. This spring releases energy when it comes back to its original position and this force is called pushing force.
Tensile helical spring is a spring in which its length increases after applying load but after the removal of load spring returns to its original shape.
In both types load is applied parallel to spring axis. When we look this spring type depending upon the geometry it also has two types.
Closely coiled helical spring is a type of spring in which there is very less space between two turns and helix angle is less than 10° which means that each turn is almost at right angle.
Open coiled helical spring is a type of spring in which there is considerable difference between each turn. In this type helix angle is greater than 10°.
Conical and volute springs
Conical springs are said to be compressed conical springs and by changing their angle of helix, ending, material. These springs are available in only round shape made of high carbon steel wire. The pitch of these springs is variable and changes at every point. They are made like telescoping spring as partial and complete telescoping. In it we less active coils than total number of coils because top and bottom end coils are fixed which means that if any spring has 6 coils then it will definitely has 4 active coils used for operation.
On the other hand volute coils are also similar to conical springs but they have parabolic shape. The pitch of these coils is same. These springs have friction between each turn so it means that this spring best suits to vibration damper. Similarly they have benefits over helical springs so we can say that this spring is the modified form because it has more lateral stability and non-linearity of their load.
This type of springs has number of flat plates of varying lengths and each length hold together with clamps and bolts. We use these springs mostly in vehicles to absorb shocks produced by unbalancing of vehicle. Major stresses that are produced in this spring are compressive and tensile.
This spring is made by conical discs and remains at the place against slipping by central bolt or tube. We can use these springs where we need high spring rates and compact spring unit.
This spring can be in two shapes either in helical or in spiral. Helical type spring may be used where load can wind up the springs and is used in various electrical mechanisms. On the other hand spiral type is used where number of coils of spring increases as we increase load. This type is use in clocks and watches. Major stresses in torsion springs are compressive and tensile due to bending.
Special purpose springs
These springs can found in any shape like ring, rubber, air or liquid springs. The purpose of using these springs is to do special task only.