The block is designed to simulate planetary gear mesh of the "Sun-Planet" type with a constant gear ratio and constant efficiency. The gearing is a worm gear, i.e. the worm gear is the planet gear and the gear is the sun gear of the planetary gear. The kinematic diagram of the gearbox is shown in the figure (Figure 1).
Figure 1. Kinematic diagram of the planetary worm gear Sun-Planet
Planetary gear consists of:
Sun gear, which is the gear of the worm gear
W (worm), which is a planet gear
Carrier C
The block is described by the following kinematic relation:
where:
ωS – angular speed of the sun gear, rad/s
ωC – angular speed of the carrier, rad/s
ωW – angular speed of the worm gear, rad/s
dir – value indicating the matching of the directions of rotation of the shafts of the gear and the worm gear, has a value of 1 or -1
U – worm gear ratio
To meet the requirement of the kinematic ratio, the block solves the coupling equation. A detailed description of the approach for the the gear (speed) ratios simulation is given on the page Simulating transmission. A detailed description of the approach for simulation losses in the gearing is given on the page Gearbox efficiency simulation.
The calculation of the gearbox efficiency is carried out depending on the gearing geometric characteristics:
where:
νWG – efficiency when transmitting power from the worm gear to the gear
νGW – efficiency when transmitting power from the gear to the worm gear
α – normal pressure angle, °
λ – lead angle of the worm, °
μ – friction factor
The gear ratio value U is displayed next to the block.
Inputs
Name
Description
Connection line type
S
Port for connecting the sun gear shaft
Rotary mechanics
W
Port for connecting the worm gear shaft
Rotary mechanics
C
Port for connecting the carrier (carrier)
Rotary mechanics
Outputs
Name
Description
Connection line type
Q
Power losses due to bearing friction and gear meshing (efficiency)
Mathematical
Properties
Title
Parameter
Description
By default
Data type
Kinematics
A group of properties that set the kinematic parameters of motion
Allows you to define the friction model. The possible values are: "No loss", "Set efficiency manually", "Calculate efficiency by geometry", "Table data efficiency on temperature"
The value of the power transmitted through the block, below which the efficiency is increased to achieve the stability of the numerical solution. The property is available when selecting the following friction models: "No loss", "Set efficiency manually", "Calculate efficiency by geometry", "Table data efficiency on temperature"
Worm-to-gear transmission efficiency. The property is available when selecting the friction model "Calculate efficiency by geometry" and is displayed in the "Read-only" mode, is for reference only
Gear-to-worm transmission efficiency. The property is available when selecting the friction model "Calculate efficiency by geometry" and is displayed in the "Read-only" mode, is for reference only
Array of the worm-to-gear transmission efficiency values
Nu_wg_Arr
Array of the worm-to-gear transmission efficiency values. Efficiency values are calculated by linear interpolation depending on the temperature values. The property is available when selecting the friction model "Table data efficiency on temperature"
Array of the gear-to-worm transmission efficiency values
Nu_gw_Arr
Array of the gear-to-worm transmission efficiency values. Efficiency values are calculated by linear interpolation depending on the temperature values. The property is available when selecting the friction model "Table data efficiency on temperature"
