The document discusses a sliding mesh gear box. It describes the gear box as a collection of mechanical components that deliver power from an engine through a series of gear ratios to operate a transmission. It then explains that a gear box provides variable torque ratios for acceleration and climbing gradients and allows for reversing vehicle motion. It notes that sliding mesh gear boxes typically have 3 forward gears and 1 reverse gear, using spur gears that slide to engage gears on the main shaft with those on the lay shaft/counter shaft. The document concludes by outlining the power flow path through gear engagement in low, medium, and high gears and how the reverse gear operates through an idler gear.

1. TRANSMISSION SYSTEM
VISHWAVIDYALAYA ENGINEERING COLLEGE
LAKHANPUR
SARGUJA UNIVERSITY

2. SLIDING MESH GEAR BOX
PRESENTATION BY
VINIT LAHARI

3. CONTENT
• INTRODUCTION
• SLIDING MESH GEAR BOX
• FUNCTION OF A GEAR BOX
• POWER FLOW PATH IN GEAR

4. INTRODUCTION
A gearbox is a collection of mechanical
components that deliver maximum power
from an engine by managing a series of gear
ratios that in turn operate a transmission.

5. Function Of A Gear Box
• Torque ratio between the engine and wheels
to be varied for rapid acceleration and for
climbing gradients.
• It provides means of reversal of vehicle
motion.
• Transmission can be disconnected from engine
by neutral position of gear box

6. Sliding Mesh Gear Box
• Normally 3 forward and 1 reverse gear ratios
• Spur gears are used
• Gear wheels on the main shaft engage with
gear wheels on the lay shaft (counter shaft) by
sliding themselves.
• Not used in automobiles now

7. POWER FLOW PATH IN GEAR
ENGAGEMENT
•When engine is running and the clutch is engaged, clutch shaft gear
drives the drive gear of the lay shaft and thus lay shaft also rotates.
•But the main shaft remains stationary as no gears in main shaft are
engaged with lay shaft gears.

8. •Low speed
•High acceleration

9. •Slightly less acceleration
•Bit more speed

10. • Even less acceleration
•Even high speed

11. •By operating gearshift lever, the larger gear of main
shaft is meshed with reverse idler gear.
•The reverse idler gear is always on the mesh with
counter shaft reverse gear. Interposing the idler gear.

12. THANK YOU