Transmission System Outside the Gearbox

Question 1

What is one of the functions of the synchromesh?

Answer 1

To equalise the rotational speeds of the gear wheels

Question 2

What is the process called when the synchromesh eliminates the difference in rotational speeds in a gearbox?

Answer 2

Synchronising

Question 3

Which gears are equipped with a synchronising device on this gearbox?

Answer 3

The forward gears

Question 4

The synchromesh doesn’t apply to reverse gear. What is the reverse gear process called? How does it work?

Answer 4

Sliding mesh
The gear wheels slide into contact

Question 5

Sliding mesh is how rerverse gear operates. Is it synchronised?

Answer 5

No

Question 6

List 7 components of a locking synchroniser

Answer 6

Synchroniser sleeve
Synchroniser hub
Locking pin
Tensioner spring
Needle-roller bearing
Synchromesh ring
Conical gear

Question 7

What component connects the output shaft to the gear wheel on the output shaft?

Answer 7

The synchroniser sleeve

Question 8

One of these 2 rotational speeds does not change, regardless of the gear setting. Which one:
The speed of the input shaft
The speed of the output shaft

Answer 8

The input shaft

Question 9

What is essential in synchronising the speeds of the output shaft and synchroniser?

Answer 9

The input shaft needs to be interrupted temporarily using the clutch

Question 10

Give 2 other names for the synchromesh-ring

Answer 10

Synchro-cone
Baulk ring

Question 11

Where are the internal grooves of the synchromesh in the cross section?

Answer 11

Where the syncromesh ring touches the conical gear (the friction surface

Question 12

What are the 2 main functions of the fine grooves on the inside of the synchromesh ring?

Answer 12

To drain excess lubricant from the 2 friction surfaces to increase friction
To hold a small amount of lubricant to minimise wear

Question 13

What are synchromesh rings usually made of? Why?

Answer 13

Brass
It can handle friction very well

Question 14

List 3 things that occur when the synchroniser sleeve shifts

Answer 14

The locking pin slides against the raised edge of the synchromesh-ring
The synchromesh-ring slides against the conical surface of the gear
The synchroniser sleeve pushes the locking pin down against the spring force

Question 15

Which component limits how much the synchromesh-ring can rotate?

Answer 15

The locking pin(s)

Question 16

Which 2 factors make the baulk ring move, with respect to the locking pin/synchroniser sleeve?

Answer 16

The increasing friction between the surfaces of the baulk ring and the conical gear
The difference in speeds of the baulk ring and the conical gear

Question 17

What factor makes the synchro-cone rotate backwards, with respect to the locking pin/synchroniser sleeve?

Answer 17

The decrease in speed difference between the synchro-cone and conical gear

Question 18

Why can’t you select gears when the difference in speed between the synchro-cone and conical gear is too great?

Answer 18

The outer teeth of the synchroniser sleeve are not yet aligned

Question 19

During synchronisation, is the locking pin pushed into the centre of the recess or pushed againt the end of the recess?

Answer 19

Pushed against the end

Question 20

During synchronisation, what happens to the teeth of the baulk ring and the synchroniser sleeve?

Answer 20

They are not aligned, they slide against each other

Question 21

Friction is the result of the force n the synchromesh-ring, created by the synchroniser sleeve. Between which components is the friction generated?

Answer 21

The synchromesh ring and the conical surface of the gear

Question 22

When can a gear with a locking synchroniser be selected?

Answer 22

When the speeds of the baulk ring and gear wheel are synchronised

Question 23

List 3 tasks the synchromesh must perform

Answer 23

Synchronise speeds
Prevent engagement of unsynchronised gears
Lock the gear

Question 24

What does it mean in terms of synchronisation that reverse gear has straight-cut teeth?

Answer 24

The gear is not synchronised

Question 25

What 3 points of data do you need to calculate the vehicle speed from the engine speed?

Answer 25

The gear ratio of the gear box The ratio of the final drive in the differential The diameter of the wheels

Question 26

Where is the final drive located?

Answer 26

Directly in the centre of the 2 back wheels, in the differential housing

Question 27

Why do cars have a gearbox?

Answer 27

So they can continue to maintain their optimal engine speed, while the vehicle speed can increase or decrease

Question 28

Why do cars have a final drive? What other component also contributes to this?

Answer 28

To increase torque and reduce speed The gearbox

Question 29

What kind of transmission do the gearbox and differential use to alter torque and speed?

Answer 29

Gear wheel transmission

Question 30

Give one other name for the crown wheel in the differential

Answer 30

Ring gear

Question 31

How can you calculate gear index in the differential, using the teeth on cogs?

Answer 31

The ratio of the crown wheel's teeth, to the drive pinion's teeth

Question 32

The ring gear and drive pinion are at right angles to each other, when not turning. Which one is connected to the drive shaft? Which one is connected to the prop-shaft (propeller shaft)

Answer 32

Drive pinion Ring gear

Question 33

Out of the ring gear and the drive pinion, which one is the driver? Which one is the driven?

Answer 33

Drive pinion Ring gear

Question 34

When steering left, which side of the car needs to travel faster and further?

Answer 34

The right side

Question 35

List 2 functions of the differential

Answer 35

Enable a difference in speed between the driven wheels Ensure drive through 90 degrees to the rear wheels

Question 36

What would happen to the car while turning left if there were no differential?

Answer 36

The left wheels would continue to rotate as fast as the right wheels, while covering less distance and therefore wear quicker

Question 37

Where is the rear subframe located?

Answer 37

Around/above the drive shaft

Question 38

Name the main 3 kinds of differential found in 4-wheel drive cars

Answer 38

Front differential Centre differential Rear differential

Question 39

In a 4-wheel drive car, there is no prop-shaft. What takes its place to connect the front and rear of the car?

Answer 39

A drive shaft

Question 40

List 6 components that make up a differential. Which 3 are there 2 of?

Answer 40

A ring gear A drive pinion A differential carrier 2 pinion gears 2 side gears 2 axle shafts

Question 41

What is the rear axle?

Answer 41

The whole area at the rear, including the wheels, drive shaft and rear subframe

Question 42

What gear drives the ring gear?

Answer 42

The drive pinion

Question 43

If the engine speed is 100 rpm and there is no braking, what is the wheel speed? If the differential makes the left wheel brake 50%, what with the wheel speed of the right wheel be?

Answer 43

100 rpm 150 rpm

Question 44

What is the disadvantage of a differential?

Answer 44

Torque is only transferred if both wheels have grip