Model: 066 Square Gears
This type of gearing transmits a variable speed. The top gear is the driver and has a constant speed. The lower gear runs slow when the corners are up in position and faster when driver engages the flat sides. This type is not commonly used.
[Virginia Downward & William M. Clark, 1930]

[Editor’s Note: The rolling of square gears on each other demonstrates a basic principle of Reuleaux that any planar motion of two bodies can be represented by the pure rolling of one body on another. These rolling curves are called "centrode curves" The two square gears are such a pair of centrode curves. Clark copied this model from the 1868 book of mechanical movements by Henry T.Brown, Figure 30. FCM]

Francis Moon 2005-00-00