1. Clutch and Manual Transmission

2. Clutches 2

3. Clutches What is clutch? Cone clutch Multi plate clutch
=A device that connects the engine to transmission by engaging and disengaging the single plate dry or multiple disc clutch to the flywheel.
=Components :disc plate, pressure plate, flywheel, throwing out bearing, diaphragm spring.
Cone clutch
Multi plate clutch
Coil spring clutch 3

4. Clutches What’s the clutch components?
Main components:disc plate, pressure plate, flywheel, throwing out bearing, diaphragm spring.
(1)clutch plate (2)clutch cover (3)pressure plate, (4) diaphragm spring for the clamp load, (5) tangential leaf spring as a spring-loaded connection between the cover and pressure plate for providing pressure plate lift, (6)the fulcrum ring and the (7) diaphragm rivet for positioning and providing a mounting for the diaphragm spring. (8) clutch driven plate with individual parts consisting of the (9) torsion damper with (10) friction device and (12) hub, stop pin (23), the segment cushion spring (22) and the facings riveted to them (11). The flywheel (13) with the spigot (pilot) (15) bearing. The release mechanism with (18) release bearing guide tube (gearbox quill), (19) release bearing and (20) release fork. 4

5. Clutches What is the purpose?
Provide transmission of power from one component (driving member) to another (driven member).
i.e: devices with two rotating shafts. one shaft is attached to a motor (driving member) while the other shaft (driven member) provides output power for work to be done. Three conditions:
engaged = locked together and spin at the same speed
slipping = locked together but spinning at different speeds
disengaged = unlocked and spinning at different speeds
Control the ability to limit the transmission of power or motion. i.e: control the transmission of engine power to the wheels.
Allow load to be applied to the engine gradually
Allow shift of gear while vehicle is moving 5

6. Clutches Modern clutches must also:
• enable gentle and jerk-free starting
• ensure fast gear changing of the transmission
• keep engine torsional vibrations as far away
from the transmission and thereby decreasing
noise and wear
• serve as an overload protection for the entire
drive train (e. g. in case of faulty gearchanging)
• be durable and easily replaceable 6

7. Clutches Dry and wet clutches Friction material varies in composition.
Clutch maybe "dry" or "wet“ type.
Wet clutch immersed in a lubricating fluid for cooling; to keep the surfaces clean, gives smoother performance and longer life.
May lose some energy to the liquid.
Clutch surfaces can be slippery (as with a motorcycle clutch bathed in engine oil), stacking multiple clutch disks can compensate for the lower coefficient of friction to eliminate slippage under power when fully engaged.
Dry clutch – not bathed in fluid/oil. 7

8. Clutches
Clutch for a drive shaft: The clutch disc (center) spins with the flywheel (left). To disengage, the lever is pulled (black arrow), causing a white pressure plate (right) to disengage the green clutch disc from turning the drive shaft, which turns within the thrust-bearing ring of the lever. 8

9. Powertrain and Drivetrain
Clutches
Modern car with manual transmission, clutch is operated by the left-most pedal using hydraulic or cable connection.
Clutch might be operated by a mechanical linkage.
With a rigid mechanical linkage, smooth engagement would be near-impossible because engine movement inevitably occurs as the drive is "taken up."
No pressure on the pedal means that the clutch plates are engaged (driving), while pressing the pedal disengages the clutch plates, allowing the driver to shift gears or coast. 9

10. Clutch
When clutch pedal is pressed, hydraulic piston pushes the release fork, which presses the throw-out bearing against the middle of the diaphragm spring. As the middle of the diaphragm spring is pushed in, a series of pins near the outside of the spring causes the spring to pull the pressure plate away from the clutch disc. This releases the clutch from the spinning engine.
When your foot is off the pedal, the springs push the pressure plate against the clutch disc, which in turn presses against the flywheel. This locks the engine to the transmission input shaft, causing them to spin at the same speed. 10

11. Clutch cont. Pressure Plate Clutch Plate
The amount of force the clutch can hold depends on the friction between the clutch plate and the flywheel, and how much force the spring puts on the pressure plate.
Note the springs in the clutch plate. These springs help to isolate the transmission from the shock of the clutch engaging.
Pressure Plate
Clutch Plate 11

12. Type of Clutch Other types of clutches;
Electromagnetic clutch; An air conditioning compressor in a car has an electromagnetic clutch. This allows the compressor to shut off even while the engine is running. When current flows through a magnetic coil in the clutch, the clutch engages. As soon as the current stops, such as when you turn off your air conditioning, the clutch disengages.
Centrifugal clutches; Centrifugal clutches are often found in lawn mowers, go-karts, mopeds and mini-bikes. These clutches work automatically through the use of centrifugal force. The input is connected to the engine crankshaft. The output can drive a chain, belt or shaft. As the rotations per minute increase, weighted arms swing out and force the clutch to engage. 12

13. Type of Transmission Automobile Transmission Automatic Manual
Semi-automatic
Continuous Variable Transmission (CVT)
Planetary Gearing Transmission
Dual-Clutch
Manumatic Transmission 13

14. Introduction
The need for a transmission in an automobile is a consequence of the characteristics of the internal combustion engine. Engines typically operate over a range of 600 to about 7000 revolutions per minute (rpm), while the car's wheels rotate between 0 rpm and around 1800 rpm.　
Furthermore, the engine provides its highest torque outputs approximately in the middle of its range, while often the greatest torque is required when the vehicle is moving from rest or travelling slowly. Therefore, a system that transforms the engine's output so that it can supply high torque at low speeds, but also operate at highway speeds with the motor still operating within its limits, is required. Transmissions perform this transformation. 14

15. Manual Transmission
Manual transmissions often feature a driver-operated clutch and a movable gear selector.
Most automobile manual transmissions allow the driver to select any gear at any time.
However, a sequential manual transmission that those commonly mounted on motorcycles and some types of racing cars, only allow the driver to select the next-highest or next-lowest gear ratio. 15

16. 2-Speed Transmission
The green shaft comes from the engine through the clutch. The green shaft and green gear are connected as a single unit.
The red shaft and gears are called the layshaft. These are also connected as a single piece, so all of the gears on the layshaft and the layshaft itself spin as one unit. The green shaft and the red shaft are directly connected through their meshed gears so that if the green shaft is spinning, so is the red shaft. In this way, the layshaft receives its power directly from the engine whenever the clutch is engaged. 16

17. 2-Speed Transmission2
The yellow shaft is a splined shaft that connects directly to the drive shaft through the differential to the drive wheels of the car. If the wheels are spinning, the yellow shaft is spinning.
The blue gears ride on bearings, so they spin on the yellow shaft. If the engine is off but the car is coasting, the yellow shaft can turn inside the blue gears while the blue gears and the layshaft are motionless. 17

18. 2-Speed Transmission3
The purpose of the collar is to connect one of the two blue gears to the yellow drive shaft. The collar is connected, through the splines, directly to the yellow shaft and spins with the yellow shaft. However, the collar can slide left or right along the yellow shaft to engage either of the blue gears. Teeth on the collar, called dog teeth, fit into holes on the sides of the blue gears to engage them. 18

19. 5-Speed Transmission
The five-speed manual transmission is fairly standard on cars today. Internally, it looks something like this. 19

20. Reverse Gear Reverse gear is handled by a small idler gear (purple).
At all times, the blue reverse gear in this diagram is turning in a direction opposite to all of the other blue gears.
Therefore, it would be impossible to throw the transmission into reverse while the car is moving forward -- the dog teeth would never engage.
However, they will make a lot of noise. 20

21. Synchronizer
A synchronizer purpose is to allow the collar and the gear to make frictional contact before the dog teeth make contact.
This lets the collar and the gear synchronize their speeds before the teeth need to engage.
The cone on the blue gear fits into the cone-shaped area in the collar, and friction between the cone and the collar synchronize the collar and the gear.
The outer portion of the collar then slides so that the dog teeth can engage the gear. 21

22. Gear Ratio
A five-speed transmission applies one of five different gear ratios to the input shaft to produce a different rpm value at the output shaft. Here are some typical gear ratios. 22

23. 6-Speed Transmission
Mercedes-Benz C-class sport coupe, six-speed manual transmission, graphic illustration 23