It is a type of steam engine where a pivoted overhead beam is used to apply the force from a vertical piston to a vertical connecting rod.
It is basically a 6 link mechanism that converts rotary motion of crank into linear straight line motion of vertical sliding link that in practice is used in pumps and other purposes.
2. WHAT IS A MECHANISM ?
• A mechanism is a group of links
connected to each other by joints, to
form a kinematic chain with one link
fixed, to transmit force and motion.
It is design to do a specific motion.
• Mechanism is also define as
the combination of geometrical
bodies which constitute a machine or
part of a machine.
3. INTRODUCTION TO KINEMATIC CHAIN
• In mechanical engineering, a kinematic
chain is an assembly of rigid bodies
connected by joints to provide
constrained motion that is the
mathematical model for a mechanical
system. As in the familiar use of the
word chain, the rigid bodies, or links, are
constrained by their connections to other
links.
Four Bar Chain
Single Slider Crank Chain
Double Slider Crank Chain
4. INTRODUCTION TO BEAM ENGINE
(AN INVERSION OF FOUR BAR KINEMATIC CHAIN)
• It is a type of steam engine where a pivoted
overhead beam is used to apply the force
from a vertical piston to a vertical
connecting rod.
• It is basically a 6 link mechanism that
converts rotary motion of crank into linear
straight line motion of vertical sliding link
that in practice is used in pumps and other
purposes.
Beam Engine
5. HISTORY OF BEAM ENGINE
• Newcomen Beam Engine. The engine was
invented by Thomas Newcomen in 1712. It was
the first machine to be powered by steam and was
largely used to pump water out of mines.
• Beam engines were extensively used to power
pumps on the English canal system when it was
expanded by means of locks early in
the Industrial Revolution, and also to drain water
from mines in the same period, and as winding
engines Thomas Newcomen
Actual Beam Engine
6. CONSTRUCTION OF BEAM ENGINE
Beam Engine has simple construction and it consist of 5
parts they are, Fixed Frame, connecting rod, crank and
piston cylinder arrangement.
1. In this mechanism frame i.e Link 1 is made fixed.
Crank is connected with pin on the frame itself.
2. Connecting rod is used to connect the crank and beam
for motion transfer.
3. Beam is mounted on the vertical column with
coinciding centers. A circular pin is used to hold the
beam.
4. The other end of beam is connected to the piston
cylinder arrangement to obtain the reciprocating
motion of piston inside the cylinder.
Construction of Beam Engine
7. WORKING OF BEAM ENGINE
• In this mechanism four bar kinematic chain is
upto ABCD only.
• The main purpose of the mechanism is to
convert the rotary motion of crank into
reciprocating motion using oscillating beam.
• In this mechanism when the crank rotates about
fixed center the beam oscillates about its center.
At the end of the beam the additional linkage of
piston rod and piston is connected which
reciprocates inside the cylinder. Hence the
oscillating motion of beam is converted into the
reciprocating motion of piston.
Actual Working of Beam Engine
Schematic Diagram
8. DEGREE OF FREEDOM
• In mechanics, Degrees Of Freedom (DOF) of a mechanical system is the number of independent parameters
that define its configuration .It can also be defined as the number of variables required to determine the
position of mechanism in space.
It can be determined using Kutzbach criteria :-
F = 3(N-1)-2L- 1H
Here,
F = degree of freedom ,
N = number of links ,
L = number of lower pairs ,
H = number of higher pairs
Beam engine has 1 degrees of freedom i.e. rotation of link about its perpendicular to plane and vertical motion.
9. ADVANTAGES OF BEAM ENGINE
• It is a mechanism which can be used for converting rotary motion into reciprocating motion
which can be used in a number of applications like slitting , sawing , shaping etc.
• We can also obtain reverse effect such that reciprocating motion provided to the
mechanism can be converted to rotary motion.
• It is a major mechanism in context to the energy sector because it is the mechanism which is
used to pump oil out from the earth.
10. DISADVANTAGES OF BEAM ENGINE
• It cannot be used at places where variable motion is required without using other
accessories.
• There are four joints in the mechanism , at these joints friction will take place causing wear
which will demand need for maintenance of the mechanism.
• In the case of reciprocating motion quick return is not possible.
11. APPLICATIONS OF BEAM ENGINE
• It is used to draw out water from mines, as well
as to pump water into canals.
• This mechanism is widely used in steam
engines but nowadays it is used in water pumps,
oil rings, specially sewing machine.
• It is type of steam engine where a pivoted
overhead beam is used to apply the force from a
vertical piston to a vertical connecting rod
• It is used in hacksaw machines for metal
cutting.
Mini Hacksaw
Pumpjack
12. PRACTICAL APPLICATION OF BEAM ENGINE
As we have seen that beam engine can be used to
obtain reciprocating motion if it is provided with
rotary motion we can use the reciprocating
motion for the purpose of crushing food
ingredients for the making of sauces or
traditional Indian chutney by using a piston and
cylinder arrangement at the reciprocating end .
Chutney maker using beam engine mechanism
13. REFERENCES
• Theory of machines - R.S. Khurmi and J.K. Gupta
• https://www.brainkart.com/article/Kinematic-Inversions-of-4-bar-chain-and-slider-crank-
chains_6274/#:~:text=Inversions%20of%20four%20bar%20chain,mechanism%20or%20doubl
e%20lever%20mechanism.
• https://www.nitsri.ac.in/Department/Mechanical%20Engineering/MEC_403_Part_3_KINEMA
TICS_OF_MACHINERY.pdf
• https://extrudesign.com/four-bar-mechanism-inversions/