The 11 1⁄2 ligne windup movement Shanghai SB1 belongs is a rare to find chinese windup movement, in contrast to the ubiquitous movements of the ZSE/ZSH series.
Current movements like the R16-1 base on that construction, which is easy to see on the gear train and on the base plate.
The speciality of this movement is, that it has got a modern gear train with second wheel and dial-side indirectly driven hands. Since no center minute wheel is used, the height of the movement is reduced, and the available space for the mainspring barrel and the balance wheel is increased almost till the center of the movement.
The gear train is state of the (swiss) art: Mainspring barrel, second wheel with slip clutch, third wheel, directly driven center seconds wheel and escape wheel.
All bearings, except for the mainspring barrel and for the center seconds arbour on the dial side are equipped with synthetic rubies.
The thin, four-leg anular balance is beared in two chinese shock protections, which strongly remind of a swiss Incabloc shock protection. The balance regulares a classical swiss-type pallet lever movement.
Of course, this movement has got a yoke winding system on the dial side.
|Number of jewels:||17|
Nickel anular balance|
China (different types)|
|Balance bearing / direction hairspring:||Counterclockwise|
|Adjust mechanism:||Hairspring key|
|Construction type:||solid construction|
|Winding mechanism:||yoke winding system|
|Setting lever spring:||2 hole(s)|
|Functions:||hour, minute, second|
|Size:||11 1/2''' (measured: 25,6mm)|