BZUPAGES.COM PRESENTED BY : BILAL GROUP PRESENTATION PRESENTED TO : SIR IMDAD ULLAH.
Bilal gear presentation
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Transcript of Bilal gear presentation
TEXTILE MATHS
TEXTILE MATHS:
The mathematics which is related to textile is known as textile mathematics.
It includes graphical representation, sizes , number theory and algebra. It is used in weaving, knitting, crocheting and in embroidery.
What is Gear? A gear or cogwheel is a
rotating machine part having cut teeth, or cogs, which mesh with another toothed part in order to transmit torque.
A device or mechanism to change the direction of motion.
In most cases with teeth on the one gear being of identical shape, and often also with that shape on the other gear.
TYPES OF GEARS1. According to the position of axis
of the shafts -
(a.) Parallel
(b.) Intersecting
(c.) Non-Intersecting and non-parallel
TYPES OF GEARS
Planetary units with helical gears, rather than spur gears, have higher torque capacity and run quieter. Different manufacturers measure and rate backlash in different ways. Planetary gear heads are high-precision, motion-control devices that generate substantial torque for their size, have high torsional stiffness, and low backlash — making them suited for wide-ranging tasks.
Planetary gears
(a.) Parallel and co-planar shafts
(i) Spur Gear -They consist of a cylinder or disk with the teeth projecting radially.
This is a very common gear and it is important which is used in every machine.
(ii) Helical Gear-The leading edges of the teeth are not parallel to the axis of rotation, but are set at an angle. This gear reduces the noise.
Spur Gear
Helical Gear
(b.) Intersecting/ non-parallel and Co-planer Shaft
Bevel Gear - Two non-parallel and intersecting, but co-planer shafts are connected by the bevel gear and the arrangement is called bevel gearing.
Bevel gears, like spur gears may also have their teeth inclined to the face of the bevel, in this case they are known as helical bevel gears.
This gear changes the direction and the both gears are in same direction.
Bevel Gear A bevel gear is shaped
like a right circular cone with most of its tip cut off.
The angle between the shafts can be anything except zero or 180 degrees.
When two bevel gears mesh, their imaginary vertices must occupy the same point.
Spiral Bevels
Spiral bevel gears have the same advantages and disadvantages relative to their straight-cut cousins as helical gears do to spur gears.
Straight bevel gears are generally used only at speeds below 5 m / s (1000 ft/min), or, for small gears, 1000 r.p.m.
TYPES OF GEARS
GEAR TRAIN: The combination of two or more gears.
DRIVER: The motor is directly connected. DRIVEN: The motor is not directly connected. CARRIER/IDLER: An external gear which is put
between two gears to make the both gears direction same. Every idler is a carrier.
SHAFT: The motor which is concerned with gear is called main shaft.
(c) Non-Intersecting and non-parallel and Non Co-planar
This types of shafts are connected by gears known as "Skew Bevel Gear“ or "Spiral Gear" and the arrangement is known as "Skew Bevel Gearing".
TYPES OF GEAR
HARMONIC GEAR: The Harmonic Drive Gear belongs to the group of strain wave gears. The Flexspline is slightly smaller in diameter than the Circular Spline resulting in it having two fewer teeth on its outer circumference. It is held in an elliptical shape.
Worm Gear Worm gears
resemble screws. A worm gear is usually meshed with a spur gear or a helical gear, which is called the gear, wheel, or worm wheel.
To achieve a high torque, low speed gear ratio.
TYPES OF GEARS
PULLEY:A pulley is a wheel on an axle or shaft that
is designed to support movement and change of direction of a cable or belt along its circumference. Pulleys are used in a variety of ways to lift loads, apply forces, and to transmit power.
TYPES OF GEAR
PLANETARY GEAR: Planetary gears also refer as epicyclic gearing
consisting three elements sun gear, planet gear and ring gear. Sun gear is located at the center that transmits torque to planet gears orbiting around the sun gear. Both systems are located inside the ring gear. In the toothed formation sun and planet gears are externally mesh and ring gear internally meshes.
Planetary gear system is use in varies applications such as clocks, lunar calendar, car mirror, toys, gear head motor, turbine engine and many more.
2. According to the Peripheral Velocity of the Gears
(a.) Low Velocity ( Less than 3 m / s )
(b.) Medium Velocity ( 3-15 m / s )
(c.) High Velocity ( Greater than 15 m / s )
3. ACCORDING TO TYPE OF GEARING (a.) External Gearing
(b.) Internal Gearing
(c.) Both Internal and External
(a.) External Gearing
In external Gearing, the two shafts mesh externally with each other.
The larger of two wheels is wheel or Gear and the smaller wheel is called pinion.
In an external gearing, the motion of the two wheels is always unlike or opposite.
(b.) Internal Gearing
In internal gearing, the two gears mesh internally with each other.
The larger of these two wheels is called Annular Wheel and the smaller wheel or gear is called Pinion.
In internal gearing the motion of the wheels is always same or like.
(c.) Both Internal and External
The gear of two shaft meshes externally and internally with the gears in a straight line. Such type of gear is called Rack and Pinion.
The straight line gear is called Rack and the circular wheel is called Pinion.
With the help of Rack and Pinion we can convert Linear motion into rotary motion and vice-versa.
GEARS RELATED TO TEXTILE
GEARS ARE USED IN CIRCULAR MOTION IN TEXTILE INDUSTRY.
GEARS ARE ALSO USED IN CIRCULAR LOOMS, PROJECTILE LOOMS AND MANY OTHER LOOMS.
CIRCULAR MOTION OBJECT HAS ALWAYS A GEAR.
USES OF GEAR IN DAILY LIFE
Gears are used in many machines. Many are machines we use in our everyday life, such as cars; wind up toys, clocks, mixers, bikes, oil rigs, vacuum etc. Gears make our lives easier in many ways.
They allow us to change direction and speed of movement, measure time and create a great force “mechanical output” with a little force input.
Cars: A car has at least a first, second, third and fourth gear. These
are the different sized gears that fit together in the car. The engine turns a set of gears that are joined to a rod called the crankshaft.
Clocks: Many clocks and watches today are electronic but, gears have
been used for a long time to run mechanical clocks like pendulum and mainspring clocks.
NUMERICALS ON GEAR
SPEEDDRIVER: 495TEETHDRIVER: 57SPEEDDRIVEN : 29TEETHDRIVEN : ?BY USING FORMULA:TEETHDRIVEN= SPEEDDRIVER*TEETHDRIVER
SPEEDDRIVEN
TEETHDRIVEN= 495 *57/29
TEETHDRIVEN=973
NUMERICALS ON GEAR
DRIVER = DRIVENRPM OF DIVER=120TEETH OF DRIVER=30RPM OF DRIVEN=?TEETH OF DRIVEN=50RPM OF DRIVER*TEETH OF DRIVER = RPM OF DRIVEN*TEETH
OF DRIVENRPM OF DRIVEN= RPM OF DRIVER*TEETH OF DRIVER /TEETH
OF DRIVENRPM OF DRIVEN=120*30/50RPM OF DRIVEN=72
NUMERICALS OF GEAR
RPM OF DRIVER*TEETH OF DRIVER = RPM OF DRIVEN* TEETH OF DRIVEN
120 * 30 = 72 * 50 3600 = 3600SO, RPM OF DRIVER*TEETH OF DRIVER = RPM OF
DRIVEN* TEETH OF DRIVEN
BIBLIOGRAPHY
http://machinedesign.com/mechanical-drives/planetary-gears-review-basic-design-criteria-and-new-options-sizing
http://harmonicdrive.de/en/technology/harmonic-driver-strain-wave-gears/
http://www.ehow.com/list_6928131_examples-gears-pulleys.html
http://www.odec.ca/projects/2006/seef6s2/everyday.htm