WOLFRAM SYSTEM MODELER

PlanetaryGear

Class containing a basic planetary gear model

Diagram

Wolfram Language

In[1]:=
SystemModel["RotatingMachinery.Gears.PlanetaryGears.PlanetaryGear"]
Out[1]:=

Information

Planetary Gear

Planetary gear consisting of three elements: sun gear, planet gears and ring gear, [1–4]. The sun gear is located at the center. The planet gears are mounted on a carrier and revolve around the sun gear. Both systems are located inside the ring gear.

The sun and planet gears are externally meshed and the ring gear is internally meshed. Many different variations and arrangements of planetary gears can be found, including applications such as clocks, car mirrors, toys, turbine engines and the more familiar automatic car gearboxes and wind turbines.

Figure 1 shows an animation of the planetary gear, and also naming of the wheels.

Figure 1: Planetary gear.

Figure 2 displays the parameters of the planetary gear system, including number of teeth, modules and profile shift. The initial angles of the gearwheels are also calculated in the parameters tab so that the gears teeth are in contact. 

Figure 2: Planetary gear parameters tab.

The theory around planetary gears can be found [5].

References

[1]  Dahl, M., H. Wettergren, and H. Tidefelt. "Modelica Spur Gears with Hertzian Contact Forces." Proceedings of the 12th International Modelica Conference, Prague, Czech Republic, May 15-17, 2017. Linköping Electronic Conference Proceedings 132, no. 82 (2017): 755-763. http://dx.doi.org/10.3384/ecp17132755.

[2] Van der Lunden, F. L. J. and P. H. Vazques de Souza Silva. "Modelling and Simulating the Efficiency and Elasticity of Gearboxes." Proceedings of the 7th International Modelica Conference, Como; Italy, Sep 20-22, 2009. Linköping Electronic Conference Proceedings 43, no. 29 (2009): 270-277. http://dx.doi.org/10.3384/ecp09430052.

[3] Kosenko, I. and I. Gusev. "Implementation of the Spur Involute Gear Model on Modelica." Proceedings of the 8th International Modelica Conference, Dresden; Germany, Mar 20-22, 2011. Linköping Electronic Conference Proceedings 63, no. 35 (2011): 315-328. https://ep.liu.se/ecp/063/035/ecp11063035.pdf.

[4]  B. Paul. Kinematics and Dynamics of Planar Machinery. Prentice Hall, 1979. 

[5]  Wikipedia. "Epicylic Gearing". https://en.wikipedia.org/wiki/Epicyclic_gearing.

Parameters (16)

m

Value:

Type: Module (m)

Description: Gear module

alpha0

Value: 20 * Modelica.Constants.pi / 180

Type: Angle (rad)

Description: Reference profile angle

zs

Value:

Type: Integer

Description: Number of teeth for sunwheel

xs

Value: 0

Type: Real

Description: Profile shift for sunwheel

zp

Value:

Type: Integer

Description: Number of teeth for planetwheel

xp

Value: 0

Type: Real

Description: Profile shift for planetwheel

zr

Value:

Type: Integer

Description: Number of teeth for ringwheel

xr

Value: 0

Type: Real

Description: Profile shift for ringwheel

initialAnglePlanetShaft1

Value: 0

Type: Angle_deg (°)

Description: Angle of planet shaft. Normally 360/3*i

initialAnglePlanetShaft2

Value: 120

Type: Angle_deg (°)

Description: Angle of planet shaft. Normally 360/3*i

initialAnglePlanetShaft3

Value: 240

Type: Angle_deg (°)

Description: Angle of planet shaft. Normally 360/3*i

initialRotationSunWheel

Value: initialAnglePlanetShaft1 - 360 / zs * floor(initialAnglePlanetShaft1 / 360 * zs)

Type: Angle_deg (°)

Description: Gear wheel 1 initial angle of rotation

initialRotationPlanetWheel1

Value: 180 + initialAnglePlanetShaft1 - 360 / zp * (floor((180 + initialAnglePlanetShaft1) / 360 * zp) + 0.5)

Type: Angle_deg (°)

Description: Planet wheel 1 initial angle of rotation

initialRotationPlanetWheel2

Value: initialRotationPlanetWheel1 + (initialAnglePlanetShaft2 - initialAnglePlanetShaft1) * (zp / zp + zs / zp - 1)

Type: Angle_deg (°)

Description: Planet wheel 2 initial angle of rotation

initialRotationPlanetWheel3

Value: initialRotationPlanetWheel1 + (initialAnglePlanetShaft3 - initialAnglePlanetShaft1) * (zp / zp + zs / zp - 1)

Type: Angle_deg (°)

Description: Planet wheel 3 initial angle of rotation

InitialRotationWheelRingWheel

Value: initialAnglePlanetShaft1 + initialRotationPlanetWheel1 * zp / zs

Type: Angle_deg (°)

Description: Sun wheel initial angle of rotation

Connectors (4)

frame_sun_b

Type: Frame_b

Description: Coordinate system fixed to the component with one cut-force and cut-torque (non-filled rectangular icon)

frame_sun_a

Type: Frame_a

Description: Coordinate system fixed to the component with one cut-force and cut-torque (filled rectangular icon)

frame_carrier

Type: Frame_a

Description: Coordinate system fixed to the component with one cut-force and cut-torque (filled rectangular icon)

frame_ring

Type: Frame_a

Description: Coordinate system fixed to the component with one cut-force and cut-torque (filled rectangular icon)

Components (15)

sunWheel

Type: SpurGear

Description: Spur gear with mass, rotations and visualization

ringWheel

Type: SpurGear

Description: Spur gear with mass, rotations and visualization

planetaryWheel1

Type: PlanetWheel

Description: Planet wheel to be used in PlanetaryGears

fixedTranslation

Type: FixedTranslation

Description: Fixed translation of frame_b with respect to frame_a

fixedTranslation1

Type: FixedTranslation

Description: Fixed translation of frame_b with respect to frame_a

gearForceCalculation

Type: GearForceCalculation

Description: Class calculating gear mesh contact forces

gearForceCalculationInner

Type: GearForceCalculationInner

Description: Class calculating internal gear mesh contact forces

planetaryWheel2

Type: PlanetWheel

Description: Planet wheel to be used in PlanetaryGears

gearForceCalculation1

Type: GearForceCalculation

Description: Class calculating gear mesh contact forces

gearForceCalculationInner1

Type: GearForceCalculationInner

Description: Class calculating internal gear mesh contact forces

planetaryWheel3

Type: PlanetWheel

Description: Planet wheel to be used in PlanetaryGears

gearForceCalculation2

Type: GearForceCalculation

Description: Class calculating gear mesh contact forces

gearForceCalculationInner2

Type: GearForceCalculationInner

Description: Class calculating internal gear mesh contact forces

cylindricalBeam

Type: CylindricalBeam

Description: Class with a flexible cylindrical beam

cylindricalBeam1

Type: CylindricalBeam

Description: Class with a flexible cylindrical beam

Used in Examples (2)

PlanetaryGear

RotatingMachinery.Examples.Gears.PlanetaryGears

A basic planetary gear application; WindTurbine Part I

WindTurbineGearBox

RotatingMachinery.Examples.Gears.PlanetaryGears

Assembly of a planetary gear and a three-shafted gearbox; Part I and Part II