Lorsa 82
Description
The Lorsa 82, a windup movement with diameter of 8 3/4 lignes, made in France, dates from around the mid 1970s until the early 1980s and was one of the last tiny windup movements from France.
The contemporaneous offered tonneau shaped version of this movement was the Lorsa 81. Both are technically equivalent.
base plate
The execution of this movement is standard; of course all important bearings contain rubies.
gear train
The gear train follows the usual conventions for movements of this size: Mainspring barrel, directly driven center minute wheel, tiny third- and fourth wheel and finally a large steel escape wheel.
The additional space, compared with the tonneau version of the Lorsa 81 is not used at all.
side view of the gear train
Due to the limited space, the lower bearings of third- and seconds wheel are above the escape wheel.
movement w/o center seconds
The ratchet is the only different part compared with the Lorsa 81, because it consists of two parts, the click pawl and the a spring, which tends to fly away easily. Both are located below the ratchet wheel, and not easy to mount for a watchmaker.
gear train with center seconds
The seconds wheel is beared on top by the center seconds bridge. The center seconds pinion is driven by a flying beared, just put onto an axle, transmission wheel, located at position 4 o’clock.
The drawback of this construction is, that as soon as the flying transmission wheel touches the bridge or the slightest part of dust is between this wheel and the bridge, so much friction is applied, that the amplitude goes down dramatically.
side view with center seconds
As escapement, a swiss pallet lever escapement is used.
It is controlled by the three-leg anular balance, which beats with 21600 A/h and is beared in two Antichoc-102- bearings.
The frequency can only be regulated directly at the hairspring key.
Lorsa 82: Dial side
We have the expected view on the dial side, we see the woke winding system and we can see the two bearings of the third- and seconds wheel, which are above (seen from the movement side) the escape wheel.
Timegrapher result
On the timegrapher, it made almost the same good impression, as the Lorsa 81, and also here, with a little higher amplitude, it would have run in all positions within the chronometer specs, at least in five of the six positions| horizontal positions | |||
|---|---|---|---|
| dial up | +5 s/d | 264° | 0.0ms |
| dial down | -1 s/d | 258° | 0.2ms |
| vertical positions | |||
| crown right (12 up) | +6 s/d | 217° | 0.1ms |
| crown up (3 up) | -18 s/d | 240° | 0.3ms |
| crown left (6 up) | -1 s/d | 221° | 0.4ms |
| crown down (9 up) | -5 s/d | 226° | 0.3ms |
Technical data
| Manufacturer: | Lorsa |
| Caliber: | 82 |
| Size: | 8 3/4''' (measured: 19,3mm) |
| A/h: | 21600 |
| lift angle: | 52° |
| Number of jewels: | 17 |
| Escapement: | Pallet lever |
| Balance types: |
Nickel anular balance |
| Shock protection(s): |
Antichoc 102 |
| Balance bearing / direction hairspring: | Counterclockwise |
| Moveable stud: | yes |
| Adjust mechanism: | Long regulator arm |
| Construction: |
|
| Construction type: | solid construction |
| Winding mechanism: | yoke winding system |
| Setting lever spring: | 6 hole(s) |
| Features: |
|
| References: |
Frankreich: 1976 |
| Inventory number: | 23049 |
Usage gallery
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