Description
The AM 617 is a relatively modern constructed and well made cylinder movement of the late time of movements with cylinder escapement.
Video on YouTubeWith 10 jewels, a cylinder movement has got its full equipment with rubies - so on this movement, too. In theory, you could add two additional jewels to the minute wheel, but until now, I’ve never seen such a cylinder movement.
Cylinder movements were build until the mid of last century. Compared to lever movements, they were cheaper and simpler, since they contained one less moving part - the lever . The disadvantage of there movements were, that the sharp teeth of the cylinder wheel always were in contact with the balance cylinder, thus breaking a little bit. On wear of these teeth and on magnetizing, it was soon stopped.
Besides this, cylinder movement were rather inprecise - a daily rate of one or two minutes per day was not unusual.
The AM 617 is one of the few small cylinder movements, which already used a yoke winding system. This is remarkable, since it means, that a rather cheap movement got a rather expensive winding system.
In terms of quality, this is very positive!
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At position “9”, you see the T-shaped escapement module, which consists of the balance bearing on the dial side and the balance cock as a unit. This constructions allows a precise depthing setting of the balance cylinder into the cylinder wheel, which is required for reliable function.
At “1”, you can see the “Ebauches Trust” hallmark.
Technical data
| Manufacturer: | AM |
| Caliber: | 617 |
| Size: | 8 3/4''' (measured: 19,1mm) |
| A/h: | 18000 |
| Number of jewels: | 10 |
| Escapement: | Cylinder |
| Balance types: |
Nickel anular balance |
| Shock protection(s): |
none |
| Balance bearing / direction hairspring: | Clockwise |
| Moveable stud: | no |
| Adjust mechanism: | Long regulator arm |
| Construction: |
|
| Construction type: | solid construction |
| Winding mechanism: | yoke winding system |
| Setting lever spring: | 3 hole(s) |
| References: |
Ebauches: 1928 Flume: 1947 97 |