Early usage of hair dryer in France and further evolution of hair dryers.
The function of a hair dryer is not only to dry your hair faster but also to allow you to style your hair as it dries. Hair, when washed would dry naturally too but it would take longer. To speed up this process, a hair dryer uses a fan to blow air over the hair. The movement of air helps to take away the moisture from the hair, thus speeding up the drying process.
Blow dryers were invented at the end of 19th century. These were used by professional stylists in the salons and in the average house hold consumers. Before the invention of hair dryer, vacuum cleaner was used as hair dryer for drying hair. By taking inspiration from vacuum cleaner, Alexander Godefroy created hair dryer in 1890 and used in his salon, in France. It was neither handheld nor portable but could only be used by having women to sit underneath it.
The first handheld, household model appeared in the market in 1920. The product is further developed changing the material to plastic and light weight but the mechanism never changed since inception.
To quicken the drying of the hair, a heater is used. When the fan of the hair dryer blows air across the heater, warm air is moved across the wet hair and dries it faster.
In addition to the heater and fan, common hair dryers have a switch to control the speed of the fan. A few hair dryers even have a switch to control the temperature of the heater. These switches help to control the speed at which the hair dries.
The function of the safety grill over the air inlet is to prevent external objects like strands of hair from being sucked into the fan.
As the inside of the hair dryer is at a high temperature, the hair dryer nozzle as well as the entire body must be properly insulated to make it safe for the person using it.