Optionalmodule: numberOptionalpinionTeeth: numberOptionalringTeeth: numberOptionalpressureAngle: numberOptionaladdendum: numberOptionalmoduleThe module both gears share, in model units.
OptionalpinionHow many teeth the spur gear has, at least 3. Fewer than about 20 interfere with a standard ring of any size.
OptionalringThe ring's teeth: more than the spur gear's, and enough to keep their tips outside its base circle, 34 at 20 degrees with an addendum of 1.
OptionalpressureThe pressure angle both gears share, in degrees.
OptionaladdendumHow far the teeth of both reach beyond their pitch circles, as a share of the module.
A spur gear meshing inside a ring gear, for
engineering.mechanical.gears.internalGearPair: the module and pressure angle they share and their teeth.