Model 36: step-dwell mechanism

Kinematic scheme:

Explanation:

The mechanism
consists of a superposition of a crank-slider mechanism and a planetary gear
pair. The coupler AB and the planet wheel (radius r=AB) are part of the same
body. The rotation centre of the sun wheel coincides with the crank rotation
centre A For certain
dimensions this mechanism will make a continuous stepping motion of the sun
gear. The usual application is to drive a belt with intermittent motion, as
sometimes required in production machinery. The (infinitesimal) dwell is
short, but the motion is very smooth, see the graph below. |

Dimensions:

The
output step b
of the sun gear can be a whole division n>1 of one revolution of the input
crank angle a.
In the model n=6, so the output step is 60 deg. For a given
value of the sun gear radius R Planet gear radius r = R Crank length
a = R |

Literature:

Remarks: