A mechanism of oscillating link or reciprocating slider that moves forward slowly and returns quickly.
o Offset slider-crank mechanism.
o In-line slider-crank mechanism.
Used for specific output motion.
Follower displacement is a function of cam angle.
Main types of follower
a) Translating roller follower.
b) Translating flat-faced follower.
c) Rotating roller follower.
d) Rotating flat-faced follo
1) Translating flat-faced follower with/without offset
rb and s are known, l is unknown.
c rb s e
xc rb s S lC
yc rb s C lS
Slope @ c T
s C rb s S l S lC
s S rb s C l C lS
s C rb s S l
Gear with teeth are cut at an angle with respect to gear axis.
Used for parallel shafts.
o Less shocks.
o Smoother and quieter operation.
o Larger load transmission.
o High contact ratio, C r 3 .
C rH C rS wT p .
Relatively large face wi
o Circle of friction wheel.
o Tangent to the other one.
o Rolls on the other one without slipping.
Pitch point: contact point of pitch circles.
Velocity ratio rv
o v p 1r
Introduction to Mechanisms
Planar motion: motion in a single plane or in a set of parallel planes.
Spatial Motion: motion in three dimensions.
Kinematics: the study of motion (x, v, a) without reference to the forces or torques.
Dynamics: the study of mot
Drive Trains (Gear Trains)
A combination of two or more meshing gears.
Generally used in motors, engines, watches,
Used as speed reducer generating high torque.
Spur gear train
o Simple: each shaft carries only one gear.
N2 N3 N 4 N5 N2
o External wheels: opposite direction of rotation.
o vc 1r 2 R
o Internal wheels: same direction of rotation.
Belt drive chain drive
o vb 1r 2 R
Complex Numbers Notation
Complex number (z) = x + j y
x: real part.
jy: imaginary part.
z1 = 3 + i 2
z2 = 0 i 1 = i
Complex Numbers Representation
z x2 y2