My last clock, Electra, was created in response to feedback that potential customers were looking for a clock that did not require winding. To achieve this, I incorporated a “remontoire” (from the French remonter, meaning “to wind’) mechanism that uses a small electric motor to raise a weight approximately every 20 minutes. You can see the remontoire operate at about the 60 second point in the video below. I am very happy with the design and operation of this clock; it has been running very reliably for about 3 months and keeps great time.
To regulate time keeping, all my recent clocks use a torsional pendulums (a lager wooden disc containing lead weights) that rotates back and forth on a long steel spring. On my wall mounted clocks the torsional pendulum hangs in front of the clock mechanism. I have received comments that this makes the torsional pendulum and spring vulnerable to being knocked and is also a visual distraction from the clock mechanism.
My aim in the design of the new clock – Electra 2 – is to modify the design of the Electra clock to relocate the torsional pendulum behind the clock mechanism. This has proved easier said than done and I have designed and rejected 2 concepts before developing one that I like and I hope should work.
The challenge is to create a clock with a smaller diameter torsional pendulum so that it fits behind the clock wheels, design a frame that holds all the elements of the clock mechanism in the appropriate locations, but does not clash with the torsional pendulum spring while remaining an aesthetically pleasing design. Below is an image of the design that I have come up with from the CAD (Computer Aided Design) software (TurboCAD) that I use to create all my clocks.
Another feature that I have changed is the geared electric motor that powers the remontoire. The electric motor on the Electra clock was larger and more powerful than really needed and the gear mechanism makes a noticeable whirring noise when it operates. I have found a source of much smaller electric motors manufactured by Pololu (https://www.pololu.com/) that appear to meet my requirements and are very quiet. The motor I chose is nominally 12-volt (although it runs well using a 9-volt battery) and has a 1000:1 gear ratio.
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