Gents of Leicester Master Clock
Circa 1900
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This clock is 51 inches tall and was built about 1900. It was extremely accurate for the time because
the pendulum would only receive an impulse once every 30 seconds. The very heavy pendulum would
free swing for 29 seconds between impulses. For 58 seconds of every minute there was no friction or
interference from any source other than the resistance of the air in the case.
There were 30 teeth on the impulse wheel. Between the 29th and the 30th tooth, the valley was deeper than the others.
As the impulse lever would reach the deeper valley, the lever would drop further into the wheel, causing the control arm
to strike the latching lever pushing it off of its lock. This would cause the contact arm to drop down and make contact
with the other side of the assemble closing an electrical contact. When the contact was closed, the DC voltage went through
the solenoid coil causing the lever to throw control arm back up to the control latch where it would be locked for the next
29 seconds.
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At the same time the impulse goes to the solenoid to relock or cock the impulse lever, the same voltage goes
to the coil of the clock train causing it to advance 30 seconds. The pulse could also go to other slave clocks
throughout a building to cause them to also advance 30 seconds. The clock is extremely accurate and if it has a weakness, it is that
the contact points draw a small arc each time it cycles and over time the contact points burn and need to be sanded or replaced.
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