Categories

Knowledge

Working principle and characteristics of planetary gears
Sep 03, 2018

The planetary gears mechanism has three moving parts that can rotate relative to each other: the sun wheel, the planetary frame and the gear ring. It can realize four different combinations of gears:

1. The sun gear with low gear is active, the planet rack is passive, and the gear ring is not moving.

2. The sun gear is stationary, the planet rack is passive, and the gear ring is active.

3. The sun gear is not active, the planet rack is active, the gear ring is passive.

4. The sun gear is reversed, the planet rack is not moved, the gear ring is passive.

When all the moving parts are not restrained, the transmission is in neutral.

The planetary gears transmission is usually composed of two or three planetary gear mechanisms, and the combination of the above moving parts is controlled by a multi-plate clutch to achieve different gear positions.


2222.jpeg


Transmission combination:

In the gear system with planetary gear, the transmission principle is different from that of Dingzhou gear. Because of the planetary frame, there are three rotating shafts that allow power input/output, and clutches or brakes that limit the rotation of one of the shafts when needed, leaving only two shafts to drive. Therefore, there are many combinations of meshing gears.

(1) The power is input from the sun wheel and output from the outer gear ring, and the planet rack is locked by mechanism.

(2)Power input from sun gear, output from planet carrier, outer ring gear is locked.

(3)The power is input from the planet carrier, output from the sun wheel, and the outer gear ring is locked.

(4) The power is input from the planet carrier, output from the outer gear ring, and the sun wheel is locked.

(5) Power input from outer gear ring, from planetary frame output, sun wheel locking;

(6) Power is input from outer gear ring, output from sun gear, and planetary frame is locked.

(7) The two power is input from the sun gear and the outer gear ring respectively.

(8) The two power is input from the planet carrier and the sun wheel respectively.

(9) The two power is input from planetary frame and outer gear ring, and then output from the sun wheel.

(10)The power input from the sun wheel is divided into two parts: the outer gear ring and the planet carrier output.

(11) The power input from the planet carrier is divided into two parts: the sun gear and the outer gear ring.

(12)The power outer gear ring input is divided into two ways: output from sun gear and planet carrier.



Motion characteristics:

According to the above combination, the motion characteristics of the simple planetary gear mechanism can be summarized as follows:

(1)  When the planet carrier is an active part, the driven part is overrunning.

(2) When the planet carrier is a follower, the planetary frame must be lower than the speed of the active component.

(3)  When the planet carrier is fixed, the active parts and the driven parts rotate in the opposite direction.

(4)  When the sun wheel is an active part, the speed of the follower inevitably falls.

(5)  If the planet carrier acts as a passive component, its rotation direction and active component are the same.

(6)If the planet carrier acts as an active part, the direction of the rotation of the passive component is the same as that of the planet carrier.

(7)  In the simple planetary gear mechanism, the number of the sun gear is the least, the equivalent number of the planetary gear is the most, and the number of the ring gear is between the middle. (Note: the equivalent number of teeth on the planet rack = the number of teeth of the sun gear teeth.

(8)  If any two elements of a planetary gear mechanism rotate at the same speed and in the same direction, the rotational speed and direction of the third element must be the same as those of the first two, that is, the mechanism is locked and becomes a direct gear. (this is a very important feature.)

(9)  Only when one active part and two other components are not fixed, they are in neutral at this time.

3333.jpeg


 *For more detailed parameters,size,price.Pls contact the Hangzhou Starred-River Machinery Co., Ltd.

 Tel:+86-571-89988766

  E-mail:802@china-sr.com

  Website:http://www.srgearboxes.com

  Wechat18257963886

  Facebook:0086 18257963886

  Whatsapp:0086 18257963886

  • QR CODE
  • facebook