How hand dryers work and the types

The hand dryer generally works on the principle that the sensor detects a signal (hand) and this signal looks at the control to open the heating circuit relay and the blowing circuit relay to start heating and blowing. When the signal detected by the sensor disappears, the contact is released and the heating circuit and the blowing circuit relay is disconnected to stop heating and blowing.
Heating device
The heating device has no heating device, PTC, electric heating wire.
1、No heating device, as the name implies no heating device
Suitable for places where the temperature requirements are more demanding and where the hand dryer is used frequently.
For example: frozen vegetables, frozen dumplings packaging workshop
2、PTC heating
PTC thermistor heating, because with the change of ambient temperature, PTC heating power also changes, in winter PTC heating power increases, the dryer blowing warm air temperature rise also increases, energy saving and environmental protection.
PTC is characterized by good temperature constancy, but also has certain disadvantages, that is, no electric wire temperature up quickly.

3、Electric wire heating
The traditional electric heating wire heating, wind temperature rise quickly, but the wind temperature constancy is poor, easy to wind temperature high, the hands have burns.
High-speed hand dryers use electric heating wire plus CPU with temperature sensor control to achieve the effect of fast and constant wind temperature rise, even when the wind speed is up to 100 m / s, the hand dryer can also blow a constant temperature wind.
Usually, the noise level of the hand dryer is relatively high for the wind-based heating hand dryer, while the noise level of the heating-based hot air hand dryer is low, so companies can choose according to their actual situation.
Electric type
Electric motors are one of the core components of automatic induction high-speed hand dryers and come in the form of: capacitor asynchronous motors, shaded-pole motors, series excitation motors, DC motors and permanent magnet motors. Capacitor asynchronous motors, shaded-pole motors and DC motor-driven hand dryers have the advantage of low noise, while series-excited motors and permanent magnet motors-driven automatic induction high-speed hand dryers have the advantage of high airflow.\

Hand drying methods
Heating based and high speed air drying types
The typical feature of this type of hand dryer is that the wind temperature is very high, relying on the relatively high temperature of the wind to take the water away from the hands, this way of drying the hands is relatively slow, generally more than 30 seconds, the advantage is that the noise is small, so it is favoured by office buildings and other spaces that need to be quiet.
High speed wind type hand dryer, characterised by very high wind speed, up to 130 m/s or more, drying hands in 10 seconds or less, heating power is also relatively low, only a few hundred watts, its heating function is only to maintain comfort, basically does not affect the speed of drying hands. Because of its fast hand drying speed, it is welcomed by places such as food factories, pharmaceutical plants, electronics factories, high-end office buildings (with good sound insulation), etc. It is also recommended by environmentalists because of its low energy consumption and the fact that it dries hands at about the same speed as hand towels.