The Baumgartner (BFG) caliber 911 is modern built ladies’ watch movement, which contains in the version with date indication a mechanism for it.
The Baumgartner 911 does not use (or uses just a few) bearing jewels, depending on the demands.
The base plate tells you, that we have a pillar construction in Roskopf type: There’s no center minute wheel, since both hands (minute and hour) are driven on the dial side by a double clutch wheel on top of the mainspring barrel. This is the reason for the large cutout in the center of the base plate.
The gear train is, although it is a Roskopf construction, a modern one, the mainspring barrel drives (besides the hands on the dial side) the second wheel, followed by third wheel, center seconds wheel (which does not carry a center second hand on some versions) and the escapement wheel, into which the pin lever engages.
Its balance is secured in two KIF Protechoc systems (or without shock protection and with only one single cap ruby) and contains a finger for the escapement. The escapement anchor in located in one jewel on the movement side; on the dial side, there’s just a metal bearing. On this way, the unusual number of five jewels on the shock protected version is achieved. Other versions only have got one jewel in total.
The Baumgartner 911 already works with 21600 A/h, that’s more or the less the maximum, I’ve yet seen on a pin lever movement.
The winding mechanism is a yoke winding mechanism, which is normally a feature of “better” movements, but the BFG 911 is in fact a “better” pin lever movement, too, which sometime even reminds of a pallet lever movement.
The ratchet consists of a simple, geniously shaped spring, which is located below the ratchet wheel. A very efficient and cost-efficient construction.
The lower side of the mainspring barrel shows the Roskopf construction: A large wheel, which drives the minute hand and a small wheel to drive the hour hand are both mounted with a slipping clutch on the mainspring barrel.
The date mechanism is unusually complicated, with gears, that contains teeths in different lengths, with springs and moveable jumpers. Because of this, the date switches semi-fast in only 45 minutes and can be corrected semi-fast, too, by turning back to 10:30pm.
|Number of jewels:||1/5/17|
Nickel anular balance|
|Balance bearing / direction hairspring:||Counterclockwise|
|Adjust mechanism:||Hairspring key|
|Winding mechanism:||yoke winding system|
|Setting lever spring:||1 hole(s)|
|Functions:||hour, minute, (second), (day)|
|Size:||8 1/2''' (measured: 19,2mm)|