Difference Between Engine and Transmission

Main Difference

The main difference between the engine and the transmission is that an Engine is a machine that converts different forms of energy into mechanical energy, whereas Transmission is the machine that controls the use of power produced by an engine in a power transmission system.

Engine vs. Transmission

We use different types of machines in our daily life to make our work easy. For example, a car, washing machine, sewing machine, etc. These machines are made up of different parts that have different functions.

Similarly, engine and transmission are two systems that are present in bigger machines. Here, the engine is a machine that is used to convert different forms of energy into mechanical energy to perform different functions. On the other side, a transmission is a machine that is used to control the usage of power in a power transmission system.

There are different kinds of engines like a heat engine; it produces mechanical energy through heat by burning the fuel in a combustion chamber. Moreover, electric motor changes electrical energy into mechanical motion, etc. On the flip side, transmission refers to the gearbox that includes gear trains and gears. They play their role in the conversion of torque and speed from a spinning power source to another device.

The engine is categorized by the input and output of energy whereas, the transmission is categorized by how gear switching is attained, i.e., manual or automatic.

Comparison Chart

EngineTransmission
A machine that converts different forms of energy into mechanical energy to perform different functions is known as an engine.A machine that controls the usage of power produced by an engine in a power transmission system is known as transmission.
Refers To
It refers to different types of engines, e.g., heat engine, electric motor, and hydraulic motors, etc.Transmission refers to the gearbox that includes gear trains and gears etc.
Categorized By
The engine is categorized by the input and output of energy.The transmission is categorized by how gear switching is attained, i.e., either manual or automatic.

What is the Engine?

The term ‘engine’ came from an Old French word ‘engin’ and the Latin “ingenium,” i.e., the root of the word ingenious. It is a machine that is used to change different forms of energy into mechanical energy.

An engine is also known as a motor. These two words have different meanings, but they use interchangeably. The term motor is derived from the Latin word “moto,” which stands for “to set in motion,” or “maintain motion.” So, the motor is a device that causes motion. The term motor was first of all users at the time of the invention of the internal combustion engine to separate it from the steam engine.

Types of Engine

An engine can be classified on the basis of two different criteria, i.e., the form of energy that an engine can use to cause motion, and the second one is the type of motion produced by the engine. So, there are different types of engines, i.e., heat engines, physically powered motors, electric motors, and hydraulic motors, etc.

  • A heat engine causes the combustion of fuel to produce heat. This heat is then changed into force. Some common examples of heat engines are present in rockets, cars, wristwatches, and nuclear submarines.
  • Electric motors are the motors that are powered by electricity, i.e., they use electrical energy to cause mechanical motion. Dynamo, machine tools, household appliances, industrial fans, and generators, etc. are examples of electric motors.
  • Myosins or molecular motors are found in muscles. They use chemical energy to produce force to cause motion.
  • A hydraulic motor is a type of engine that uses pressurized fluid to get its motion. They are mostly used to cause motion and move heavy loads.
  • Physically powered engines are the engines that run on kinetic or potential energy. These engines include elastic bands, pneumatic motors, and clockwork motors, etc.

What is Transmission?

A machine in a power transmission system that controls the usage of power produced by an engine is known as transmission. According to British English, the term transmission stands for the whole drivetrain that comprises of a gearbox, prop shaft (for rear-wheel drive), clutch, differential, and final drive shafts, etc. But, according to American English, transmission refers to the gearbox alone.

The simplest transmissions are also known as gearboxes. The transmission uses different gear trains and gears to divide speed and torque conversions that are arriving from a rotating power source to a different device.

A typical transmission system is made up of a large number of gears or multiple gear ratios with the facility to switch between these gears with the increase or decrease in speed. The switching of gears may be performed either automatically or manually. The transmission is categorized by how gear switching is attained, i.e., either manual or automatic. In most of the motorized vehicles, forward and reverse control may also be integrated.

In automobiles, the transmission is mostly linked with the engine crankshaft with the help of clutch coupling, a flywheel or fluid, etc. The wheels are moved by the output from the transmission that transfers through the driveshaft to the differentials. Besides the gear reduction, the main function of a differential is to allow the wheels to spin at changing speeds at both ends of an axle, while it causes the change in the direction of the rotation.

The transmission system is most commonly used in motor vehicles. Here the power produced by the internal combustion engine is adapted by the transmission to drive the wheels. It works to reduce the speed of the higher engine to match the speed of the slower wheel. This process causes an increase in torque. A Simple form of the transmission system is also used in pedal bicycles. Here it adapts the varying rotational speeds and torques.

Key Differences

  1. A machine that converts different forms of energy into mechanical energy to perform different functions is known as engine whereas, a machine that controls the usage of power produced by an engine in a power transmission system is known as transmission.
  2. There are different types of engines, e.g., heat engine, electric motor, and hydraulic motors, etc. These engines convert different forms of energy in mechanical energy to perform different works. On the other hand, transmission refers to the gearbox that includes gear trains and gears, etc. They change torque and speed from a rotating power source to another device.
  3. The engine is categorized by the input and output of energy. On the flip side, the transmission is categorized by how gear switching is attained, i.e., either manual or automatic.

Comparison Video

YouTube video

Conclusion

The above discussion summarizes that an engine is a machine that is used to convert different forms of energy into mechanical energy to perform different functions, e.g., heat engine, electric motor, etc. On the other hand, the transmission is the machine that is used to control the application of the power produced by the engine.

Aimie Carlson

Aimie Carlson is an English language enthusiast who loves writing and has a master degree in English literature. Follow her on Twitter at @AimieCarlson

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