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A Gearless Clock
What is a gearless clock?
They have wheels but these wheels do not have cogs that mesh with other wheels.

My clock was inspired by the gearless clock built by the eminent mathematician, radar engineer and horologist Philip Woodward. (Wikipedia) It has some features in common with his clock: a count wheel turning once a minute, a wheel wth 60 pins turning once an hour and a catch or gated detent. Also, like most of my clocks, it has a daisy wheel to move the hour hand. Unlike the original it has a compound pendulum (that is, the hinge is near the middle) with a period of 5 seconds, and a rather different mechanism.

gearless clock, total gearless clock, detail Once a minute, a count wheel on the pendulum sweeps across an inclined plane fixed to the release lever, forcing the release lever down so that it engages with the pin wheel.

This unlocks the catch. The catch releases the pin wheel which presses against the release lever and impulses the pendulum.

The catch then grabs hold of the next pin on the pin wheel and holds on to it for another minute.
gearless clock, medium
This catch is referred to in the literature as a 'gated detent'.
If I do a web-search for 'gated detent' much of what I find relates to Philip Woodward's clock.
close-up of gated detent
A close-up of my gated detent, seen from behind to show the notch
which catches a pin of the pin wheel.

long clock synchronome-like clock wooden pendulums and humidity