Gears

GEARS (power transmission)

INTRODUCTION GEARS :

a cylindrical cut on the periphery to its axis

, gears are common means of transmitting power in mechanical energy.

TYPES OF GEARS Spur gear Helical gear Bevel gear Worm & worm gear Rack and pinion

SPUR G EAR

Gear tee thes are c ut parallel t o th e axis ,a nd i t i s used for p ar alle l sh af ts

HELICAL GEARS

Here gear t ee th es are no t parallel ,t hey are s pir al arou nd th e sh af t to f or um o f h el ix, s uch gear s are sus tai n to h ea vy lo ads

BE VAL GEARS Th ey are em plo yed f or tr ansm it ro ta ti on betw een t wo no n par al lel sh af t , th ey have c one -sh ap ed b ody & str ai ght t ee th es , an gel betw een tw o sh af t is 90 also kno wn as

WORM & WORM GEARS Worm g ea r is a lo ng thi n cyli nde r in w itch on e o r mo re con tin ues hel ical teethes t hat me she s wi th he lical ge ar , the y ar e us ed f or tr an smi tti ng l ar ge

RAC K & PINNION Rack is a lo ng ro d in wi tch the g ears are f orm par all el wi th o ut an y an ge l, an d pi nio n is a simple ge ar o r s pur g ear, the y are us ed f or n on par all el s haf ts

MATE RI LS USED FOR GE ARS PLASTIC STEEL CAST IRON WOOD POWDERED METAL GEARS COPPER

BRASS ALUMILUM

TO GE ARmaintain DE SIG N precise gear ratio & out put speed , gear have specially designed cogs the most popular design used to achieve this is the involutes profile , use the mathematical concept of involutes cure to space gears, cogs in a manner that efficiently keeps gear ratio perpendicular to the flat plane GE AR DESIG N

PROFILE OF GEARS

Is generated by pressure I Npoint VO LU, on T E straight W H E E L linier S rolling on the base circle, the line is tangent on the base circle & point traces the involutes profile of one side of gear tooth as the line is rolled on the circle , the angel between the line of action & the tangent of pitch is called pressure angle a pitch circle is a imaginary ring of the same dia as smooth disk that would transmit the same relative motion by friction ,as the gear does when meshed with other gear does when meshed with other gear , the radius or

I N VO LU T E W H E E L S

ELE MENT S OF GEAR T EETHS

GEAR AND PINNION ARRANGEME NT

GEAR MANUFAHURE MOULDING METHOD FORMING METHOD CUTTING GEARS FORM CUTTING GEAR GENERATING HOBBING

SHAPE R MACHINE

FORMING TO OL

HOBBING PROCESS Gear hobbling process

M I L L I N G M AC H I N E Through arbor of milling machine

MOULDING PROCESS Plastic –injection-molding process

OTH ER T YPE S O F GEA RS PLANETRY GEARS

SUN PANLNETRY GEARS

EPIC GEARS ARREGMENT

HARMONIC GEAR ARREGMENT

GEAR GENERATING

INTERNAL GEAR ARRENGMENT

MITER GEARS

NON METAL GEARS

HERRINGBONE GEAR

PR IS ENTED BY

A .J ACOB KIR AN