Ambigugears

Ambigugears is an unusual gearing system. There are three gears in a row. The first and the third gear clearly have ten teeth. If these were regular gears, then the first gear and the third gear should spin at the same speed, independent of the number of teeth of the middle gear. If the middle gear would have 10 teeth, then there would be a 10:10:10 gear ratio, which is 1:1. If the middle gear would have 9 teeth, then there would be a 10:9:10 gear ratio, which is also 1:1. However, this is not true for Ambigugears. Here, the middle gear is an intersection of a 10-teeth left-handed helical gear, and a 9-teeth right-handed helical gear. As a result, the consecutive gearing ratios are 10:10 and 9:10, so the whole gear train has an unexpected 9:10 gearing ratio. As usual, this is a proof-of-concept. Would you know a useful application of this gearing system?

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