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Presentation09: Gearings

Outline

• Introduction: power transmission with constant transmission ratio• Introduction: power transmission with constant transmission ratio.

• Simple gearings:

• Planetary gearings: kinematic inversion and equivalent simple gearing; Willis formula.

• Multi-DOFs gearings: car differential gearing.

INTRODUCTION

Simple gearingsSimple gearings(gear trains)

Planetary (or epyciclic)gearings

(car differential gearing)

SIMPLE GEARINGS

Parallel axes

(A)

(B)(B)

SIMPLE GEARINGS

Coplanar axes

(D)

(C)(C)

PLANETARY GEARINGS

Willis formula

Transmission ratio of the equivalent simple gearing:

01

n p

p

PLANETARY GEARINGS

PLANETARY GEARINGS

MULTI-DOFs GEARINGS

50 31 zz 30 1z

010 2 5z z

1 2z z1 5

0 1 P 1 3

1 3 Pz z

010 3z

3 5z z 0 2P 1 3 2P

MULTI-DOFs GEARINGS

Car differential gearing

MULTI-DOFs GEARINGS

Car differential gearing