Product Name: Snail Fan
Item No. : KX1907 Snail Fan
Dimensions: 160*120*105mm
Weight: Approximately 100g
Material: wood +EVA+ battery box + motor + plastic accessories....
Packing: 200pcs
Box specification: 600*550*450mm

I will climb up step by step, and fly forward on the leaves at the high point. The tears and sweat that the tiny sky has shed will always be there for me. I have my own sky I have my own sky. Should I lay down the heavy shell and search for where the blue sky lies? Let it float gently with the gentle breeze. Even the wounds I've endured don't feel pain. I want to climb up step by step, waiting for the sun to quietly look at its face. The small sky has a big dream. Wrapped in the heavy shell, I look up gently. I want to climb up step by step, and fly forward on the leaves at the high point. Little sky The tears and sweat that have been shed, there will always be a sky that belongs to me. Let the wind dry the tears and sweat that have been shed, there will always be a sky that belongs to me. A beautiful children's song about snails reminds us of the lovely little snails. Next, let's make a snail fan. In the hot summer, we can refresh ourselves.

Electric fans are indispensable household appliances for us to cool off and relieve the heat in summer. But do you know why when you turn on an electric fan, a cool breeze blows, making you feel refreshed? Do you know on what basis a fan rotates? I believe that by studying the experiments in this section, you will understand the scientific principles behind them.

Key points of the experiment

Gain a preliminary understanding of the working principle of electric fans through DIY handicrafts.

Experimental purpose:

Understand the structure of a simple electric fan.

Experimental cognition

It is now very difficult to find relevant information about who invented the electric fan. It is said that in 1882, Huey, the chief technician of the Kroca Zacis Engine Factory in New York, USA, "Scartz?" Hoira invented the commercial electric fan long ago. The following year, the factory began mass production. At that time, the electric fans were desktop fans with only two blades. In 1908, the Eck Engine & Electric Company in the United States successfully developed the world's earliest wheel-driven electric fan that shook left and right. This type of electric fan prevented the unnecessary 360-degree rotation for air delivery and thus became the mainstream for future sales.

Scientific principle

The main component of an electric fan is an AC motor. Its working principle is that a current-carrying coil rotates under the force of a magnetic field. The form of energy conversion is as follows: 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 will be converted into internal energy. Iii. Can an electric fan lower the indoor temperature after it starts working? The temperature inside the room not only didn't drop, but instead rose. The reason for the temperature rise is that when an electric fan is working, due to the current passing through the fan's coil, the wire has resistance, so heat is inevitably generated and released outward, thus causing the temperature to rise. But why do people feel cool and refreshing? Because there is a large amount of sweat on the human body surface, when the electric fan starts working, the indoor air will flow, which can promote the rapid evaporation of sweat. Combined with the fact that "evaporation requires the absorption of a large amount of heat", people will feel cool.

Experimental procedures

1. Get to know the experimental apparatus
2. Fix the motor to the battery box with double-sided tape.
3. Install the fan blades onto the motor, turn on the switch on the battery box, and the small fan will start to rotate.

Hint

Do not let the positive and negative terminals of the battery box wires come into direct contact to avoid burning children's hands.
Do not directly use the electricity from sockets at home or school for experiments to avoid electric shock accidents and injuries.

Science Expansion

Possible reasons why a DIY electric fan doesn't rotate.
1. Poor maintenance and long-term lack of lubricating oil. The fan shaft part must be lubricated with oil; otherwise, the fan blades cannot be driven by the motor on it. If you are at home by yourself, you can choose to turn off the power and then rotate the fan blades. If they rotate stiffly, it basically means there is no lubricating oil.
Wear and tear caused by long-term use. If a fan has been used for a long time, the motor will wear out. Once the shaft sleeve of the motor wears out, it will be very easy to burn out.
3. The fan does not rotate due to overheating. There is a motor in the fan device. Inside the motor, there is an overheat circuit breaker. If a short circuit occurs at the coil winding, the heat generation will increase rapidly in a short time. In this case, the motor will stop working.
4. The capacity of the starting capacitor has decreased. When a fan has been used for a long time, the capacitance will decrease, resulting in a reduced starting torque of the motor and an inability to drive the load.
5. Electrical fault issues, such as damaged circuits, etc.

Scientific Inquiry: The electric fan I assembled has no wind (it's reversed). What should I do?