Clutch

 Clutch 

Principle - The clutch operates on the principle of "friction."

Location - The clutch plate sits on the clutch shaft between the engine flywheel and the gearbox.

Function -

1) Transferring power from the engine to the rear wheels through the flywheel.

2) Connecting or disconnecting power from the engine to the wheels.

3) To accelerate the vehicle slowly from a stationary position.

4) To start the engine with a jerk.

5) To reduce generated vibration and heat.

6) Parking the car in place, etc.

Main parts of the clutch -

1) Driving Members:

   - Flywheel,

   - Pressure plate,

   - Driving Disc,

   - Pressure spring,

   - Releasing Levers.

2) Driven Members:

   - The disc or plate is the clutch plate.

3) Operating Members:

   - Pedal,

   - Linkage,

   - Release bearing,

   - Release fork,

   - Spring.

Types of Friction Materials:

1) Mill Board Type - Asbestos Sheet.

2) Molded Type - Matrix.

3) Oven Type - Leather, Cork, Fabric, Asbestos, Ferodo, etc. Material is used.

Types:

1) Single Plate Clutch:

   Single plate clutch is widely used in light and heavy vehicles in the present era.

Structure:

The hub of the clutch plate is splined to the gearbox clutch shaft, and torsion springs are mounted on the hub side. Friction disc lining on both sides of the clutch plate is connected with rivets, and this main part is pressed between the flywheel and pressure plate. The clutch cover is tightened with screws or nut bolts.

1) Disengage – 

When we operate the clutch pedal, the clutch linkage is pulled, and the fork moves. Consequently, the fingers are pressed by the release bearing, releasing the tension of the springs on the pressure plate, causing it to move outwards and allowing the clutch plate to rotate freely. As a result, power is disengaged from the flywheel.

2) Engage - 

When the foot is lifted from the clutch pedal, the return spring restores the pedal to its original position, along with the linkage and clutch forks returning to their initial positions. Consequently, the release bearing moves to the rear side of the fork, applying tension to the fingers which causes the clutch plate to press against the flywheel due to the pressure plate, initiating rotation with the flywheel. Power is then transmitted, and the transmission begins.

When the clutch pedal is depressed, the clutch linkage is pulled, fully disengaging the clutch. The pressure falls on the release bearing, which presses the pressure plate release lever or fingers. As the fingers are depressed, the spring on the pressure plate pulls it outwards. Consequently, the pressure of the pressure plate on the clutch plate diminishes, allowing the clutch plate to rotate freely. As the clutch plate separates from the flywheel, power is disengaged from the engine to the transmission, thus disengaging the clutch.

As soon as the foot is lifted from the clutch pedal, the pedal return spring restores the pedal to its original position. Simultaneously, the linkage and clutch fork return to their pre-positioned state. As the release bearing moves to the rear of the fork, the depressed fingers are lifted upwards, releasing the pressure. Concurrently, the compressed spring on the pressure plate returns to its original position, pressing the pressure plate down, causing the clutch plate to engage against the flywheel under pressure.

Frequently Asked Questions (FAQs):

1. What is the principle behind the operation of a clutch?

   - The clutch operates on the principle of friction, allowing for the transfer of power between the engine and the wheels.

2. Where is the clutch located in a vehicle?

   - The clutch plate sits on the clutch shaft between the engine flywheel and the gearbox.

3. What are the main functions of a clutch?

   - The main functions of a clutch include transferring power from the engine to the wheels, connecting or disconnecting power, facilitating slow acceleration, starting the engine, reducing vibration and heat, and aiding in parking maneuvers.

4. What are the primary components of a clutch?

   - The primary components of a clutch include driving members (flywheel, pressure plate, driving disc, pressure spring, releasing levers), driven members (clutch plate), and operating members (pedal, linkage, release bearing, release fork, spring).

5. What are the different types of friction materials used in clutches?

   - Clutches can use mill board type (asbestos sheet), molded type (matrix), or oven type (leather, cork, fabric, asbestos, Ferodo, etc.) friction materials.

6. Which type of clutch is commonly used in vehicles today?

   - The single plate clutch is widely used in both light and heavy vehicles in the present era.

7. How does the clutch disengage?

   - When the clutch pedal is depressed, the clutch linkage pulls the fork, pressing the release bearing against the pressure plate, which releases tension on the springs, allowing the clutch plate to rotate freely and disengage power from the flywheel.

8. How does the clutch engage?

   - When the foot is lifted from the clutch pedal, the return spring restores the pedal to its original position, causing the release bearing to apply tension to the pressure plate, pressing the clutch plate against the flywheel and initiating power transmission.

9. What happens during the engagement process?

   - When the clutch pedal is released, the clutch linkage and fork return to their initial positions, allowing the release bearing to release pressure on the pressure plate, allowing the clutch plate to engage with the flywheel under pressure.

10. Why is proper clutch operation important for vehicle performance?

   - Proper clutch operation ensures smooth power transmission, efficient acceleration, and overall vehicle performance. It also prolongs the lifespan of clutch components and contributes to a safer driving experience.