History Of Ceiling Fan
The invention of ceiling fans was a very significant contribution to mankind. It is the simplest and most affordable means to keep yourself cool in hot and humid climate. Though today we have the electrical version of the ceiling fan, it dates back to almost 500 BC.
The very first kind of fan was found in 17th century India – the ‘pankah’ that was manually operated by a servant for the kings and queens. It was basically a palm frond or a cloth that hung from a frame and it moved when the servant pulled a cord.
In 1882, Philip Diehl paved way for the first electrically powered fan when he adapted the motor used in Singer sewing machines to power the ceiling fan. As the concept caught on, in 1886 John Hunter along with his son, James, built a belt-driven ceiling fan with blades that was powered by a running water turbine. This led to the establishment of one of the largest fan companies in the US – Hunter Fan Co., of Memphis. The fans that were built during this time had two blades. They were quite popular in the southern states of the US where heat was a serious issue.
This version of the two-blade fan was upgraded to the four-blade fans, which were not only quieter but they also circulated more air. As the competition continued to grow in the market, Diehl began to make several incorporations in his original version. One important inclusion was a light unit that would have a light bulb fitted to the ceiling fan, so it would serve two functions. By 1920, Ceiling fans had become a popular household appliance in the US and gradually gained international fame. Ever since, many improvements have been made in ceiling fans, from power saver to high speed, and today, we have an array of ceiling fan varieties.
Working Principle Of The Ceiling Fan
The ceiling fan has a motor that converts electrical energy into mechanical energy. First, the capacitor of the ceiling fan torques up the electric motor, thereby causing it to start and run. As the electrical current reaches the motor, it enters coils of wire that are wrapped around a metal base. When this current passes through the wire, it creates a magnetic field which further exerts force in a clockwise motion. In this way, the electric energy is converted into mechanical energy and causes the motor coils to spin. The blades attached to the motor also start gaining motion with the spinning of the coils.
How The Ceiling Fan Cools
The mechanism behind the ceiling fan is quite simple. It is a known fact that air naturally stratifies – the lighter, warm air rises up while the cool air, that is heavy, sinks down. The rotation mechanism of the ceiling fan is built in way so as to attract the warm air upwards. As the hot air rises up, the blades of the fan slice this air and push it down. This being a continuous process causes the air in the room to circulate in the entire room. Thus, a ceiling fan only moves the air around. Contrary to the common belief, fans do not exactly cool. Rather they speed up the process of evaporation of sweat on our body, which naturally makes us feel ‘cool’.
Parts Of A Ceiling Fan
A ceiling fan has many components. They are:
- An electric motor
- Encasement that houses the electric motor
- A capacitor
- Blades, that are generally made from iron, aluminium, or plastic
- Blade irons (also known as blade brackets, blade arms, blade holders, or flanges), that connect the blades to the motor.
- A rotor, an alternative to blade irons. It was first patented by industrial designer Ron Rezek in 1991.
- Flywheel – a metal or plastic or tough rubber double-torus which is attached to the motor shaft
Type Of Motor Is Used In A Ceiling Fan
In conventional ceiling fans, single phase induction motor is used. These motors consume minimum power and hence, are also known as fractional kilowatt motors. A single phase induction motor requires only one power phase for operating. It converts the electrical energy from the power input into mechanical energy. Single phase induction motors are used in ceiling fans owing to their simple design and the fact that they are easy to repair.