Two heart wheels in gear transmitting a variable velocity ratio

1868 in Darmstadt
Schroeder, J

Two heart wheels in gear transmitting a variable velocity ratio, teaching model / J. Schröder, 1868

This teaching model of heart wheel gears illustrates the point that gears do not have to be circular, provided that their shapes are correctly matched. Gears of this type can provide a transmission of varying speed which is a useful feature in, for example, some textile machinery. This particular device was purchased from Herr J. Schröder, an educational model maker from the Polytechnic Institute in Darmstadt, Germany.

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Science Museum: Making the Modern World Gallery

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Object Number:
steel and wood
teaching model
J. Schröder

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