Poljot 2609

Description

In the late 1960, the First Moscow Watch Factory released a large 11 1/2 ligne windup caliber, Poljot 2609.

It impresses by its strict geometrical shape of the bridges and a some other construction-wise details.

This movement has got all important ruby bearings, even the minute wheel is ruby-beared.

Really odd is the ruby beared(!) transmission wheel between mainspring barrel and minute wheel gear.

The reason for this construction is unknown, especially when you take the drawbacks into account like the need for an additional transmission wheel in the winding gear train. Looking at the base plate, you can see, that it would have bean an easy task to position the barrel a little bit nearer to the center, so space problems cannot have been the problem.

A common detail is , that the center minute wheel is beared under an own bridge. It is driven by the transmission wheel described before and is because of that directly driven.

We have the usual gear train following here with third wheel, directly driven center minute wheel and escape wheel. The gear train and the whole movement is pretty flat with a height of only 3.2 millimeters.

The anular balance with its three legs is shock protected and is probably made from Glucydur.

It still beats slowly with only 18000 A/h and can be regulated at the pretty long hairspring key directly.

As escapement, a swiss pallet lever escapement is used.

To adjust the height play for different shock protections, russian movements often have a flat piece of brass, the so called spacer under the balance wheel cock.

The Poljot 2609 even uses a ruby beared changer wheel (not yet mounted here).

On the dial side, you can see the slanted outer parts of the plate, which reduces the height a little bit.

Because of that, the mainspring barrel extends the plate.

Technical data