ETA 1170

 
ETA 1170

ETA 1170

Description

With a diameter of only 7 34 lignes (about 17mm), the ETA 1170 is one of the smalles ladies’ watch movements with directly driven center seconds. For technical reasons, it built pretty high, so that it’s appearance is a bit chubby.

version with Ruby-Shock bearings

version with Ruby-Shock bearings

As usual, this movement too was available with different types of shock protection bearings. Besides the usual Incabloc shock protections, there was for example a version with the less common and probably less costly Ruby-Shock protection available.

base plate

base plate

The fact, that the base plate shows noticeable few ruby bearings, is an indication, that we have a multi-storey construction here, which is no surprise because of the small diameter.

minute wheel

minute wheel

The center minute wheel is directly driven by the mainspring and located below its own cock. This was state of the art at the time being. The dial side bearing has got no jewel bushing, only the bearing on the cock, which also works as bearing for the center seconds wheel.

To achieve a higher (and advertisable) number of jewels, this movement uses some cap jewels.

gear train

gear train

The gear train is also typical for the 1950ies: The mainspring barrel drives the center minute wheel, followed by thied wheel, center seconds wheel and (steel-) escape wheel.

In the side view, you see the unusual high building screws for crown- and ratchet wheel. While the use for the ratched wheel is understandable (manual winding and releasing with a screw driver without risk of damaging the wheels), it is superfluous on the crown wheel.

side view of the gear train

side view of the gear train

The ETA 1170 uses a swiss pallet lever escapement.

The shock protected screw balance beats contemporarily slow with 18000 A/h; its exact beating rate can be adusted with a long regulator arm.

ETA 1170: Dial side

ETA 1170: Dial side

On the dial side, the yoke winding system and the shock protection for the balance are visible, as well, as a partial minute scale, which was used to adjust the movement before a dial was applied.

Technical data

Manufacturer:ETA
Caliber:1170
Number of jewels:17
Escapement:Pallet lever
Balance types: Nickel screw balance
Shock protection(s): Incabloc
Ruby-Shock
Balance bearing / direction hairspring:Counterclockwise
Moveable stud:no
Adjust mechanism:Long regulator arm
Construction:
  • lever
  • escape wheel, seconds wheel, third wheel
  • center minute wheel
  • mainspring barrel
Winding mechanism:yoke winding system
Setting lever spring:3 hole(s)
Features:SCD
Functions:hour, minute, second
A/h:18000
Size:7 3/4''' (measured: 17,1mm)
Literature: Flume: 1949 I 33
Inventory number:19028