Mechanisms
Mechanisms are devices that transmit and convert forces and mouons from a driving force output element.
we can clasification in this way
to transmit of motion (linear motion and rotary motion )
to convert to motion (rotary to linear and rotary recirocatmg)
linear motion mechanisms
These transmit motion and force in a straight line from one point to another, for example, a lever or a pulley
levers is a ngid bar that is used ivith a point of support or a
fulcrum
tipes of levels there are three classes class 1-The load and the effort are on opposite sides class2- The load is between the effort and the The effort o between the fulcrum and the fulcrum class 3The effort o between the fulcrum and the
of the fulcrum.
fixed pulleys A fixed pulley is balanced when the effort, F, is equal to the load. R:
Moveable pulleys A moveable pulley is balanced when it iulfil this equation:
Compound pulleys This is a set of fixed and moveable pulleys, often called a block and tackle.
Rotary motion mechanisms
Friction drive
This is made up Of two or more velar by N
wheels that are in contact.
wheel 1 is called the primary drive wheel
The output wheel rotates in the opposite direction to the primary
wheel.
Pulleys with belts
There are two pulleys or wheels wheel 1
dnven wheel rorate> that are a certain distance apart
Th e>r axles are parallel and they rotate simultaneously
the rotary of one axle is transmitred to the other ia the connected
pulleys
Th e two pulleys land the two axles) rotate >n the same direct>on
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