The planetary gears have been widely used in various machinery, mainly in the following aspects:
(1) Realize the deceleration of the major transmission ratio
In the planetary gear system shown in Figure 5, if the number of teeth of each wheel is Z1 = 100, Z2 = 101, Z2 ’= 100, Z3 = 99, the transmission ratio of the input component H to the output component 1 should be 100,000. It can be seen that the planetary gear system can get a large transmission ratio as needed.
(2) To achieve compact structure of high -power transmission
The planetary gear system can use several uniformly distributed planet wheels to pass motion and power at the same time. These planet wheels can balance each other due to the centrifugal inertia and the reaction force between the tooth profiles. Therefore, the main axis is small and the transmission power is large. In addition, because it uses an internal mesh gear, it makes full use of the transmission space, and the input and output shaft is on a straight line. Therefore, the spatial size of the entire wheel system is much smaller than that of ordinary fixed axis gears under the same conditions. This wheel system is particularly suitable for aircraft.
(3) Synthesis of exercise
The synthesis of exercise is to combine the two input movements into one output movement. The degree of freedom of the differential wheel system is equal to 2. When the motion of the two components is determined, the movement of another component can be determined. Using the characteristics of a differential wheel system can achieve synthesis of movement.
The easiest sports synthetic wheel is shown in Figure 6. The speed of the planetary H. The speed of the planetary Herk is the synthesis of the wheel 1 and the wheel 3 speed. Therefore, this wheel system can be used as an additional agency. When the star frame H, solar wheel 1 or 3 are the original parts, the wheels can be used as a deceleration mechanism.
This characteristic that can be synthesized by motion synthesis can be widely used in machine tools, computing institutions and compensation adjustment devices.
(4) Realize the decomposition of exercise
The differential wheel system can also decompose the rotation of a original component into the different rotation of the other two basic components. FIG. 7 shows a brief diagram of the car re -bridge differential device. In Figure 7, the component 5 and 4 form a fixed -shaft wheel system. The wheel 4 is solidly connected with the planet frame H, and the H is equipped with a planet wheel 2 and 2 '. Gear 1, 2, 2, 3 and planetary rack H form a different dynamic wheel system. It can pass the movement of the engine to the motion of gear 5 into different movements of the solar wheel 1 and 3.
