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Planetary gear set, function - GF27.50-P-5100-01G

Transmission 722.6 

Fig 1: Identifying Planetary Gear Set Components
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Operation 

The ring gear (1) and sun gear (3) elements of a planetary gear system are alternately driven and braked by the actuating elements of the multi-plate clutch and multiple-disc brake. The planet gears (2) can turn on the internal gearing of the ring gear (1) and on the external gearing of the sun gear (3). This allows for a variety of gear ratios and the reversal of the rotation direction without the need for moving gear wheels or shift collars.

The torque and speed are converted corresponding to the lever ratios or the ratio of the number of teeth on the driven to the driving gears and is known as the gear ratio i. The overall ratio of a number of planetary gear sets connected in series is obtained by multiplying the partial ratios.

When two components of the planetary gear set are locked together, the planetary gear set is locked and turns as a closed unit.

Advantages of a planetary gear set: 

The following basic ratio possibilities can be realized 

  1. Sun gear locked

    Ring gear driving

    Planet gears driven

    Relatively low step-down ratio.

    Fig 2: Identifying Planetary Gear Set Function (1 Of 4)
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  2. Hollow gear locked

    Sun gear driving

    Planet gears driven

    Relatively high step-down ratio.

    Fig 3: Identifying Planetary Gear Set Function (2 Of 4)
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  3. Locking two elements together so that the planetary gear set turns as a unit, produces a direct power transmission (i = 1).
    Fig 4: Identifying Planetary Gear Set Function (3 Of 4)
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  4. Planetary carrier locked

    Sun gear driving

    Ring gear driven

    Direction reversal and step-down ratio.

Fig 5: Identifying Planetary Gear Set Function (4 Of 4)
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