This is a proposition that is not easy to analyze. It is not easy or complicated. It is caused by the following reasons:
Some parameters are very important, but for most consumers, they cannot be identified by themselves, even if they are, it is very troublesome and even damages the product, such as the motor;
Some parameters have little effect on the performance of the product itself, but they are related to the actual experience, such as modeling.
1.Motor
As the heart of a fan, the motor is naturally the top priority.
In terms of the principle of the motor, the motors that are slightly "high-end" on the market currently claim to use "DC brushless motors". So what is brushless technology? Compared with brushed motors, brushless motors eliminate the usual brush-commutator, and feedback the rotor position to the control circuit through the Hall sensor, so that it can know the exact time of motor phase commutation. Because brushless motors have no brushes and no related interfaces, they are cleaner, have less noise, and in fact require no maintenance and have a longer life. Keywords: low noise and long life.
As consumers, from the performance of fans, we want the noise to be as small as possible, but the root cause lies in the motor.
2.Fan leaves
If the motor is the heart of the fan, the fan blades are the hands and feet of the fan. As the core device that drives air convection, the structure of the fan blades not only affects the amount of air volume, but also determines the softness of the wind, and even affects the working noise of the fan to a certain extent.
All fan blades are made up of an odd number of leaves. Why is this? If an even number of symmetrically shaped blades are used and the balance is not adjusted well, it is easy to cause the system to resonate. If the material of the blade cannot resist the fatigue caused by vibration, it will cause the blade or the mandrel to break, so it is mostly designed as an odd fan blade with asymmetrical design about the axis. This principle is commonly used in various blade designs, including some helicopter propellers.
The more the number of wind blades, the denser the cutting air when turning, so the wind coming out will be softer and the air volume will be more stable. At the same time, as dense blades can cut the wind into smaller pieces, noise at work will be reduced accordingly. In addition to the number of blades, there is another factor affecting the quality of the wind, which is the twist angle of the blades. To put it simply, it is the angle between the blade and the circle in the center. At present, as the number of blades increases, the twist angle of the blades starts to decrease. This is because the larger the twist angle, the harder the cutting wind is when turning, and the greater the hardness of the wind coming out, otherwise the wind is softer.
Summary: The more the number of fan blades and the smaller the twist angle, the softer the fan's wind, the more stable the air volume, and the lower the noise. However, there is also a problem with dense blade distribution, that is, the fan air volume will be reduced correspondingly at the same speed.
Function
Many friends do not pay attention to the function of the fan when choosing a fan. They feel that most fans are nothing more than timing, they can shake their heads, and then "advanced" can choose different working modes. But if you study it in depth, you will find that different fans have different longest timing times and different timing intervals. Example: A fan supports up to 8 hours of timing off / on, and 8 hours can be divided by half an hour as the smallest unit to set; while B fan only supports 6 hours of timing, and can only select 1 when selecting Set the hour as the smallest unit. Obviously, A must be more humane than B when used, and the application scenarios will be more abundant. General fans, supporting a maximum of 6 hours timing design can meet most application scenarios. The longest sleep is about 8 hours, and there is probably nothing else that can last longer than sleep.
