We have seen many products that use gears in our daily lives, but do you know what principle they utilize gears?
According to its working principle, gears have the following functions:
Firstly, gears can transmit mechanical power, such as gear shifting devices in automobiles and industrial gearboxes; Secondly, gears can change the direction of motion, such as shaking devices in mechanical watches and electric fans; Thirdly, gears can reduce speed and increase torque, such as motor reducers and various variable speed mechanisms.
Below are two interesting applications of gears in automobiles and aviation, to take a specific look at the role of gears in them.
There is a mechanical structure inside a car called a differential, which is an extremely important component. When a car turns, the speed of the inner and outer wheels is different. Without a differential, the speed of the inner and outer wheels is the same, and the car will not be able to turn, or even if it can turn at low speeds, one side of the wheel will slip and cause a rollover. Moreover, cars are very fast, and without a differential at high speeds, it is absolutely impossible. The gears here on the differential not only transmit the power of the engine, but also reduce the speed through different gear ratios, while also achieving a very cool "differential" function.
In aviation, helicopters using coaxial reversal technology are favored by many countries due to their excellent performance. The propellers of this helicopter are equipped with two on the same axis. When the aircraft is flying, the rotation directions of the two propellers must be opposite to ensure the power balance of the aircraft.
From the three-dimensional model of the coaxial reverse structure, it can be seen that after two transformations, the gear smoothly changes the mechanical transmission direction, achieving two different rotation directions on the same shaft, which is very interesting. Of course, the actual structure of a helicopter is not so simple.