Manual Gearbox Flashcards
4 types of gears?
Spur
Helical
Double helical
Epicyclic
What do gears need to resist?
Wear and severe shock to provide longevity
What are the gears made from
Hardened steel
Why use a gearbox?
Effective rev ranges
Different RPM torque is varied
Load is too great engine will stall
What happens if there is only a direct connection between engine and road wheels?
Poor acceleration
Poor hill climbing
Vehicle cannot be driving well at high speeds
No neutral or reverse
How does a gearbox and clutch help?
Fuel efficiency
Allow slower vehicle speeds without slipping
Enables drivers to disconnect power
Enables a reverse
What is the purpose of the gearbox?
Achieve high speeds with good economy and good acceleration making the most of the engines performance
What are the 2 categories of gearboxes?
Manual
Automatic
Appropriate gear ratio is selected to suit….
Engine speed
Driving conditions
What enables reverse gear in the sliding mesh construction
Reverse gear and support shaft
What are the disadvantages of sliding mesh?
Excessive noise
Not smooth gear changes
Double de clutching
What is double de-clutching?
Clutch pedal down, gear lever neutral, gear lever into gear and pedal up
What is the difference between sliding mesh and constant mesh?
Use of helical and double helical Gears
Each pair of gears are constantly in contact by a dog clutch
Correct alignment by thrust washers
What does the synchronised gear box use?
A cone clutch
Where’s does the selector fork locate in the outer sleeve?
Groove in the outer circumference
