Do you know the working principle and types of electric fans?
Although the quality of life is getting better, every household will install air conditioners, but electric fans are still the cooling equipment that many families will be equipped with, but do you know the working principle, types of electric fans, and how to buy electric fans? Let's take a look at the working principle and types of electric fans and the purchasing skills of electric fans together with "Future Home Improvement Network".
1. Working principle of electric fan
There is a lot of sweat on the surface of the human body. When the electric fan works, the indoor air will flow, which can promote the rapid evaporation of sweat. Evaporation needs to absorb a lot of heat, so people will feel cool. The AC motor is the main part of the electric fan. The energized coil rotates under the force in the magnetic field, and the electrical energy is mainly converted into mechanical energy. At the same time, due to the resistance of the coil, it is inevitable that a part of the electrical energy must be converted into heat energy.
2. Types of electric fans
Electric fans are mainly divided into table fans, floor fans, ceiling fans, wall-mounted fans, air-conditioning fans, bladeless fans, etc. Ceiling fans and wall-mounted fans do not occupy floor space, and the air volume can be adjusted, but they are immovable, difficult to clean, and need to be installed; table fans and floor fans are easy to move and clean, but occupy floor space and are unsafe for children; air-conditioning fans are convenient It can be moved and cooled down slightly, but it takes up floor space and is difficult to clean; the bladeless fan is easy to move, safe, and occupies a small space, but the air volume is relatively small.
Electric fans are divided into: single-phase capacitive type, single-phase shaded-pole type, three-phase induction type, DC and AC-DC dual-purpose series-excited commutator type electric fans according to the motor structure. According to the classification of use, it can be divided into household electric fans and industrial exhaust fans.
3. How to choose an electric fan
1. Open the box and check whether the certificate and manual are attached. The nameplate of the electric fan should have the manufacturer's name, product model specification, rated power, rated voltage, power type and frequency and other indicators. Check the outer packaging and inner packaging of the electric fan. Is there any damage?
2. The appearance quality requires that the shape, line and color tone are beautiful and generous. Electroplating parts require smooth, shiny, no yellowing, no rust spots, peeling and water marks. The paint film is required to be hard and smooth, without bubbles, scratches, peeling of paint film, hanging paint or mixing of different colors.
3. Whether the decorative parts are damaged, the front and rear grilles are tightly fitted without deformation, whether the welding points of the grille wires are loose or desoldered, etc., the floor fan can be raised and lowered flexibly. Electric fans with special functions should function well.
4. Check whether the electric fan's shaking head, speed control and timing switch are consistent with the panel markings. There are many kinds of switch devices, such as keyboard type and touch type, which require safety, good flexibility, and good contact when turning on and off the power supply. If it is a key switch, when a certain key is pressed, there should be no phenomenon that two keys are connected, and each key should be pressed and reset flexibly and freely.
5. The timing device requires accurate timing, flexible rotation, no jamming phenomenon or friction panel phenomenon, and the normally open and normally closed positions should be controlled reliably.
6. When the knob and switch are operated, the pronunciation is clear and the positioning is accurate. The light touch switch command is correct and reliable. However, the speed of each gear is required to be significantly different, and the speed of slow gear should be less than 70% of that of fast gear. When the fan blade is pushed and pulled in the axial direction, its shaking is small. Look at the front and rear gaps in the middle of the motor. As long as the fan rotor rotates flexibly, the smaller the gap, the better. When checking, remove the front grille of the fan, hold the protruding part in the middle of the fan blade by hand, and push and pull it several times.
7. Fan blade inspection: slowly rotate the fan blade by hand, the fan blade rotates smoothly and easily, without touching any part, and the blade gradually stops naturally when it stops. Looking at the running track of the fan blade from the side, if there is no obvious deviation, the fan is relatively stable when it rotates at high speed. The stability of the fan is also key, and the fan should not tip over when the most unfavorable position of the fan is at a 10° angle to the plane.
8. When purchasing an electric fan, it is necessary to conduct a trial operation, turn on the power supply, and check the metal parts with a test pen. There should be no leakage. The shaking device should be consistent and stable, with low noise, no gaps and pauses, no stagnation or sudden shaking, or rattling, and the shaking angle should be greater than 80-90 degrees. It is required to be able to start in slow gear, without humming, rustling, and without vibration, whistling, and impact sound when running in fast gear. After running, within 30 minutes of operation, the motor should have no obvious hot feeling (the lower the temperature, the better the quality of the motor).
