The
camshaft is one of the most important
parts of the internal combustion engine
that regulates the opening and closing
of the inlet and exhaust valves.this
article explains the camshaft
function,working,parts,and applications.
A camshaft is a rod
featuring a series of protruding cams,
designed to transform rotary motion into
linear motion.-By
NewCams
In the case of an engine, a camshaft is
a part of the engine that regulates the
opening and closing of an IC engine¡¯s
inlet and exhaust valves. A camshaft has
more than one cam. It has many radial
cams, which displace the inlet or outlet
valve. This cam slides over the inlet
and exhaust valves.
The cam transforms the rotary motion of
the camshaft into the reciprocating
movement of the filter or follower. This
shaft allows the suction and discharge
of the fuel inside the engine.
The camshaft operation depends on the
working of the cam and the functioning
of the valve. The inlet and outlet
valves install on the cylinder head, and
cams are installed on these valves. The
cylinder head blocks the nozzle, which
permits the fuel suction or discharge
and needs reciprocating movement.
In simple words, a cam is a unit that
transforms rotary motion into linear
motion and vice versa. The cam on the
camshaft achieves displacement with a
radial turning pattern and a follower
moving vertically to the axis of
rotation. The position of the camshaft
varies according to the design of the
engine.
The main function of the
camshaft is to open the suction
valve and exhaust valve at the
appropriate time. The crankshaft
drives to this shaft. It is
linked with the crankshaft
through a belt or meshing gears.
The movement of the camshaft is
slower than the crankshaft. It
completes one revolution after
two revolutions of the
crankshaft. In a four-stroke
engine, a camshaft works in the
following way:
¡¤
As the piston moves from
TDC to BDC (downward),
it transfers its motion
to the crankshaft.
¡¤
The crank receives
piston motion and
transforms this motion
into rotary motion, and
starts rotating.
¡¤
The crankshaft is
connected to the
camshaft through a gear
or belt.
¡¤
As the crankshaft
transfers its rotary
motion to the camshaft,
the camshaft converts
this rotary motion into
reciprocating motion and
presses the inlet valve,
and opens it.
¡¤
As the valve opens, the
fuel starts to enter
the combustion chamber.
¡¤
After suction and
compression strokes, the
combusted air-fuel
mixture expands in the
chamber, which forces
the piston to move
downward.
¡¤
During the downward
motion of the piston,
again, the crankshaft
receives motion and
moves the camshaft.By
NewCams
¡¤
As the cam of the
exhaust valve receives
this motion, it presses
the exhaust valve and
opens it, which allows
exhaust gases to move
out of the combustion
chamber.-
The solid material is
most commonly used for the manufacturing
of the camshaft. This is because such
camshafts provide great rigidity. Cast
iron is also used for the manufacturing
of camshafts because cast iron delivers
more strength.
The camshafts made of the chilled iron
process can provide excellent wear
resistance because the chilling method
hardens the material. Different
materials mix with iron to generate the
most appropriate features for their
applications.
Some industries also utilize billets
when less production and excellent
quality are needed. But this process
demands high time and cost compared to
other processes. These shafts
manufacture through machining, casting,
or forging on milling and lathe
machines. They are manufactured by
forging, casting, and machining on
lathes and milling machines.-By
NewCams
It is
a special type of needle bearing
or roller that follows the cam
lobe profile. It is also
called track follower. There are
different configurations of the
cam follower, but the most
important feature is the
attachment of the cam follower
to the mating part. The yoke cam
follower has a hole in the
center, and the stud cam
follower uses a stud.
In
the absence of this camshaft
part, the cam is not very useful
because the cam takes support
from the follower to convert
rotatory motion to reciprocating
motion. The followers have cam
follower bearings that enable
the cam follower to convert
rotary motion into
reciprocating.
The follower bearings also have
different designs but are
usually manufactured with a very
thick outer ring. This thick
outer ring design of the bearing
permits the follower to absorb
high radial loads, while soft
cores can withstand high loads
without the risk of component
damage. By
NewCams
The cam follower requires balls
or needles and special materials
such as chrome or stainless
steel according to the
requirements of the application.-
2. Cam
A cam is a device that transfers
the required movement to a
follower through direct contact.
The main objective of this
camshaft part is to transform
the crankshaft¡¯s rotary motion
into linear motion.
It
has a non-circular design with a
single lobe. The follower gets
the movement by the cam as it
turns. Each engine¡¯s camshaft
has more than one cam.
The cam is installed on the
valves. It is responsible for
regulating the opening and
closing of the intake and
exhaust valves.
The cam timing is very important
for the performance of the IC
engine. The rotation of the cam
opens the cylinder¡¯s suction
valve and exhaust valve. The
proper timing of the cam is very
important to ensure that fuel is
injected and expelled at the
right time.-By
NewCams
3. Main
Journal
The
main objective of the main
journal is to maintain the
position of the camshaft when it
rotates around the engine. -By
NewCams
4.
Lobes
The
camshaft lobes spin according to
the movement of the piston. The
speed of this component varies
according to the speed of the
engine. The main objective of
the lobes is to open and shut
the inlet and outlet valves.-By
NewCams
5. Ends
The
front end of the camshaft is
designed in such a way it links
the belt with the crankshaft.
The cam¡¯s rear end uses a
special gear to rotate the motor
distributor. The ignition timing
is the same as the rest
components of the engine.-By
NewCams
6.
Bearing
The
bearing installs with the engine
main hornet. It prevents the
camshaft from destroying the
engine block if the engine
fails. The bearings assist in
maintaining perfect camshaft
rotation.-By
NewCams
A flat tappet cam is not flat in
reality. These cams contain a
small crown on the face. It is
installed where the lifter and
lobe move oppositely to each
other, and the lifter rotates on
the lobe. The lobes of this cam
are manufactured in a small
tapered design.
The
lifter must be turned to the
lobe in order to avoid
unnecessary and damaging wear.
In contrast to roller tappets,
flat tappet has low weight and
less mass. It is easy to guess
that the flat tappet is at the
dead lobe center of the cam
lobe. These cams are cheaper
than roller cams. Due to this
reason, flat cams are more
attractive.-By
NewCams
2)
Roller Cams
The rounded tip of the roller
cam allows the roller to hold
the valve open for extended
periods of time at high lift,
which affects fuel-air mixture
requirements. The shape of the
lobe also allows the valve to
open more quickly.
The main advantage of these
camshafts is that they decrease
inner friction, permit a more
violent cam profile, and favor
high speeds. These have very
high durability. In other words,
it has an unlimited useful life.
Roller cams can
be reused again and again. They
reduce friction and increase
power. It also increases service
life by reducing wear and tear.-By
NewCams
Based on the camshaft
driver member shape
1) Cylindrical Cam
This type of cam has a
cylindrical shape. It is also
known as a barrel of drum cam.
The surface of the cylindrical
cam has a groove cut. The cam
follower uses this groove cut
for its motion.
This camshaft has a cam¡¯s axis
parallel to the direction of the
follower member¡¯s motion.-By
NewCams
2) Radial
Cam
A radial cam is also called a
plat or disk cam. It is known as
a radial cam because it has an
axis perpendicular to the
direction of the follower¡¯s
movement.
This type of cam has an
irregular contour plate. This
plate uses to convert the motion
of the cam to the cam follower
or driven member motion.
-By NewCams
3)
Conjugate Cam
It has 2 rollers. The follower
or driver of this camshaft is
linked with these rollers. The
rollers tend to limit the
movements of others so that they
can remove noise and produce
quiet operations.-By
NewCams
These cams use in applications
that need the quiet working of
the camshaft.
4) Globoid
Cam
This cam has a very similar
design to a cylindrical cam. The
main difference is that the
cylindrical cam replaces via a
concave or convex assembly.-By
NewCams
5)
Spherical Cam
The spherical cam has a groove
on its curved design. It has a
spherical shape. The follower
runs across the groove. The
movement of the follower is
vertical to the rotational axis
of the spherical cam.-By
NewCams
6)
Translating Cam
This cam contains a grooved
contour plate. The follower
members oscillate along the cam
groove surface.-By
NewCams
7)
Heart-shaped Cam
It is known as a heart-shaped
cam because it has asymmetrical
heart-shaped. The follower runs
along the cam edge. It has
smooth and continuous motion.
Such a type of cam is most
commonly depleted to wound the
cable across the solenoid
squarely.-By
NewCams
8) Wedge
Cam
The end of this cam has a
pointed shape and a wide
basement. The driver has a
sliding movement relative to the
cam.-By
NewCams
9) Spiral
Cam
It is a spiral semi-circular
contour that contains a groove
on its surface. The follower of
this cam has a perpendicular
movement according to the driver
member¡¯s linear movement of the
camshaft.
-By NewCams
The camshaft gets driving
power by the crankshaft. The
crankshaft delivers its power to
the camshaft through different
means and drives it. The
camshaft driving mechanism is
given below:
1.
Chain Drive
2.
Gear Drive
3.
Belt Drive
1) Chain Drive Mechanism
In this
mechanism, a
chain sprocket
is utilized to
deliver the
crankshaft power
to the camshaft.
If the distance between the
crankshaft and the camshaft is
large, a chain drive mechanism
is operated.
In this
mechanism, the camshaft and
crankshaft move in an identical
direction. It uses a chain
tensioner to prevent the chain
system from coming loose because
loose chains cannot transfer
sufficient power from the
crankshafts to the camshafts.-By
NewCams
2) Gear Drive Mechanism
The gear drive mechanism is used
where is a required minimum
distance between the crankshaft
and camshaft. In this mechanism,
a gear drive method uses to
deliver the crankshaft¡¯s power
to the cam.
In the case of
the gear drive mechanism, the
crankshaft¡¯s driver gear meshes
with the camshaft¡¯s driven gears
(as you can see in the
below-given diagram). As the
crankshaft starts rotating, it
delivers power to the camshaft
through the driver gear. As the
driver gear rotates, it further
rotates to the driven gears,
which opens and close the inlet
and exhaust valves of the
engine.
-By NewCams
3) Belt Drive Mechanism
The working of the belt drive
mechanism is very identical to a
chain drive mechanism. There is
only a little bit of variance
between these two mechanisms,
and a belt mechanism uses a belt
for transferring crankshafts
power to the camshafts while a
chain drive mechanism uses a
chain.-By
NewCams
The main
function of the
camshaft is to
open the inlet
and exhaust
valve of an
engine by
converting the
rotary motion of
the crankshaft
into a
reciprocating
motion.-By
NewCams
¡¡
A
camshaft works
on which driving
mechanism?
A
camshaft
uses the
following
three
main
mechanisms
to
receive
power by
the
crankshaft:
¡¤
Belt
drive
mechanism
¡¤
Gear
drive
mechanism
¡¤
Chain
drive
mechanism-By
NewCams
¡¡
Why is a
camshaft needed
in an engine?
The piston
engines can¡¯t
work without a
camshaft. A
machine is
needed a
camshaft for the
proper opening
and closing of
the inlet and
exhaust valves.-By
NewCams
¡¡
What is
the function of
a camshaft?
The main
function of the
camshaft is to
open the inlet
and exhaust
valve of an
engine by
converting the
rotary motion of
the crankshaft
into a
reciprocating
motion.
The
camshaft
controls the
breathing of the
engine ¨C it
manages the
intake of the
air-fuel mixture
into the
cylinders for
combustion and
the expulsion of
exhaust gases
after
combustion.-By
NewCams
¡¡
What are the
applications of
a camshaft?
In reciprocating
engines, the
camshafts use to
close and open
the suction and
exhaust valves.-By
NewCams
¡¡
What are the
signs of a bad
camshaft?
1.
Engine
stalling
2.
The
vehicle
won¡¯t
start
3.
The
vehicle
moves
slowly
4.
Cylinder
misfire
5.
Poor
fuel
economy
6.
A
reduction
in the
engine
power
7.
Metal
debris
in the
engine
oil
8.
Check
engine
light
illumination-By
NewCams
¡¡
What are
the parts of
camshaft?
¡¤
Cam
lobes
¡¤
Base
circle
¡¤
Camshaft
ends
¡¤
Bearings/bearing
journals
¡¤
Camshaft
ends
¡¤
Lifters-By
NewCams
¡¡
What
causes a
camshaft to
fail?
¡¤
Insufficient
lubrication
¡¤
Poor
Manufacturing
¡¤
Wear and
Tear
¡¤
Wrong
Installation
¡¤
Mechanical
Over-revving
¡¤
Contaminated
oil
¡¤
Engine
Overheating-By
NewCams
¡¡
Can a car
run with a bad
camshaft?
Yes, your car
can run with a
bad camshaft,
but it¡¯s not
recommended. The
camshaft is
crucial for
opening and
closing the
engine¡¯s valves
to allow for the
intake of air
and fuel and the
expulsion of
exhaust gases.
If the camshaft
is damaged, it
can lead to poor
engine
performance or
even engine
failure.-By
NewCams