Short Answer:

The main elements of a power transmission system are the components that help transfer power from one point to another effectively. These elements include the driving element, driven element, and the intermediate system used for transmitting motion and power. In mechanical systems, parts like shafts, pulleys, belts, chains, gears, clutches, and couplings work together to deliver motion smoothly and efficiently.

In vehicles or machinery, the power transmission system carries energy from the source (like an engine or motor) to the point of use (such as wheels or tools). The main elements ensure the right speed, torque, and direction of motion are achieved for proper working of the system.

Detailed Explanation:

Main Elements of Power Transmission System

A power transmission system is designed to transmit energy from the power source to the machine or part that performs work. The main elements involved in this process are the components that help convert, control, and deliver mechanical power effectively. These elements can be grouped into driving components, driven components, and transmission or connecting elements.

1. Driving Element:
   The driving element is the component that provides the initial mechanical power or motion. It is the starting point of the power transmission system. Common driving elements include engines, electric motors, turbines, or prime movers.

• The main function of the driving element is to generate power, which can then be transferred to other mechanical parts.
• In an automobile, the internal combustion engine acts as the driving element.
• In industrial machines, an electric motor or turbine serves this purpose.

The driving element determines how much power is available for the system to use and how it will be transmitted further.

2. Driven Element:
   The driven element is the final component that receives power and performs useful work.

• Examples of driven elements include wheels, conveyors, cutting tools, pumps, or any machine component that needs energy to operate.
• The performance of the driven element depends on how effectively power is transmitted from the source.
• It may require certain speed or torque conditions, which are managed by the transmission elements in between.

3. Transmission Elements:
   Transmission elements are the connecting parts between the driving and driven elements. They are responsible for transferring power, changing speed, direction, and torque as required. Transmission elements can be mechanical, hydraulic, or electrical, depending on the system design.

Common transmission elements include:

• Shafts: Shafts are used to transmit rotational motion and torque from one component to another. They are usually made of steel and form the backbone of power transmission.
• Couplings: These are used to connect two shafts together to transmit power. They can be rigid or flexible depending on alignment and load conditions.
• Clutches: Clutches are used to engage or disengage power transmission without stopping the driving source. This allows control over motion in systems like automobiles or machines.
• Brakes: Brakes are devices used to slow down or stop the motion of the driven element by absorbing its kinetic energy.
• Belts and Pulleys: Belt drives are used for transmitting power between two shafts that are not close to each other. They are simple, flexible, and cost-effective.
• Chains and Sprockets: Chain drives are similar to belt drives but use linked chains and sprockets for better grip and higher power transmission.
• Gears: Gears are toothed wheels used to transmit motion between shafts placed at fixed distances. They provide accurate speed and torque control.
• Bearings: Bearings support the rotating shafts and reduce friction, ensuring smooth and efficient power transmission.

These elements together make sure that the mechanical power from the prime mover reaches the driven part efficiently and safely.

4. Supporting Elements:
   Some systems also include additional supporting elements like flywheels, universal joints, and lubrication systems.

• Flywheel stores rotational energy and maintains smooth power delivery.
• Universal joint allows power transmission between shafts at an angle.
• Lubrication system ensures smooth working by reducing friction and wear between parts.

5. Function of Each Element in Power Transmission:
   Each element in the system plays a specific role:

• The driving element generates power.
• The transmission elements modify, control, and transfer that power.
• The driven element performs the final task using the transmitted energy.

For example, in a car:

• The engine is the driving element.
• The gearbox, clutch, and driveshaft act as transmission elements.
• The wheels are the driven elements that move the vehicle.

6. Importance of Power Transmission Elements:
   The efficiency, speed control, safety, and performance of any machine or vehicle depend on the correct selection and arrangement of these elements. Poorly designed systems can lead to energy loss, vibration, overheating, or mechanical failure. Therefore, proper maintenance and alignment of these components are necessary for long service life and efficient operation.

Conclusion:

The main elements of a power transmission system include the driving element, driven element, and transmission components like shafts, gears, belts, chains, clutches, and couplings. Together, they help in transferring power efficiently from the source to the destination with required control over speed and torque. These elements play a vital role in the functioning of all mechanical and automotive systems, ensuring smooth and reliable power flow.