42 regulator

The help of my new friend Prof. Roger Irving was critical in allowing me to succeed with my new project. He gave me some information on the escapement geometry and part of the material to build it: I could have experienced some difficulties in finding both things here in Italy.

	The regulator has an half second pendulum and despite this the second hand marks the seconds for the pendulum is impulsed only once in its full swing. The clock runs one week each winding. To get this performance in a short case, I thought a small diameter barrel to get the whole rope wound, but a small barrel diameter means a short lever arm ,hence an heavy driving weight. Suddenly I had the idea of dividing the driving weight into two weights to keep the design symmetry. While studying this issue I came up with a new method on how to simplify the maintaining power ,essential for a regulator as it is unthinkable to stop the regulator to make its weekly winding.	watching the escapement action trough a lens
The clock on a temporary stand

I built two coaxial barrels, one for each weight : when performing the winding of one barrel, the other is on duty delivering the energy of its weight to the pendulum via the escapement, and then the same when winding the other barrel.

As simply as the Columbus egg. Even Prof. Irving, who consulted other horological enthusiast thought highly of my invention.


pendulum cock	the escapement	clock wheels

To minimize friction I designed all the pivots to run in jewels.

The pendulum cock can be moved side to side to put the clock in beat. Perhaps the most observant has not missed the incongruity of my last statement.

How can a pendulum impulsed just once in its full swing be in beat? Obviously, there is no symmetrical beat. However, there are audible noises of the escape wheel arms when they hit their lock and those are due to the contact between the pin Q and the pendulum and the contact between the two gravity arms.

Side to side movement of the pendulum is made to get the proper beat by varying the gap between the pendulum and pin Q.

preliminary trials on a temporary stand

To avoid sliding friction of pin Q upon the pendulum rod it is of primary importance that the center of the arbor of the gravity arm T lies on the same center as where the suspensions spring flexes.

Due the uncertainty of this latter point, to minimize fractions, I jeweled pin Q in the point of contact with the pendulum rod . Also jeweled is the lock B of the escape wheel arms. The pendulum rod is invar and the temperature compensation is gotten by a brass cylinder which is on top the regulating nut of the bob.

The bob height is almost the same of its diameter. Dealing with the form of the bob , there is no certainty, and some experiments have shown that the classical cylinder which fits the most of the regulators has the worst air drag coefficient ;it is possible to get best results with a cylinder of the same height and diameter.

Anyway the same experiments have shown that the best results are obtainable with other bob forms that I personally dislike because of their design. .

To maximize the height of the falls of the driving weights , approximately 3 kilos each, I installed two pulleys in the top of the case, one for each weight.

Both pulleys have screw-type groves to lead the rope in the correct position on the barrels during winding .I'm confident of the skill of a friend of mine ,Franco Fiorentino, who built the case, but I feared that the large weight supported by the upper part of the case could destroy it.

This is the reason of the artistic hook which virtually is a clamp which firmly holds the top and the back of the case together, and also supports the driving weights.

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introduction

the escapement

the regulator

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