Gear and Linkage Mechanism

Orange gear pitch diameter : 1.5R
Pink gear pitch diameter : 0.75R
Crank radius of orange gear : R
Crank radius of pink gear : 0.75R
Length of blue and green bars : 2.9R
Length of yellow bar : 2.6R
Length of violet crank : 2.5R
Distances between bearings: 2.25R + 1.5R + 3.2R
Assembly position: as start position of the simulation video.
Input : pink gear rotating regularly.
The violet crank oscillates with two dwells in one working period of 2 revolutions of the pink gear because the locus (in blue) of a cyan pin contains two portions of radius that is approximately equal to the yellow bar length.