Albert Pellaton

The contribution

The patent names Pellaton as inventor, providing firmer personal attribution than a company product page alone. The assignee is separately named. This supports credit for the disclosed construction while leaving unnamed workshop engineers and makers unassigned; it does not establish that Pellaton personally fabricated every production part. 2

The database distinguishes a 1950 priority, 1951 German filing and 1953 publication. The reproduced IWC literature points further back to a 1946 patent-related milestone and explains a revised arrangement in 1950. Because the earlier Swiss document was not read, the 1946 wording is retained as a source claim rather than silently treated as an independently verified grant date. 23

How it works

Automatic winding must turn irregular rotor motion into useful mainspring winding. The rotor may reverse direction as the watch moves; the barrel still needs to be wound in the appropriate direction. Pellaton's patented arrangement also addresses how that moving mass is supported and how the winding assembly can be disengaged or removed for service. 23

The rotor turns a shaped cam. As the cam moves between rollers, it rocks a lever carrying pawls. The pawls take turns acting on a toothed winding wheel, converting the back-and-forth part of the motion into progressive winding. The mechanism therefore uses an intermediate rocking action rather than expecting the barrel simply to follow the rotor's reversals. 23

The patent's numbered chain is rotor 18/cam 17, rollers 27 and rocker 10, then pawls 8 and 9 acting on wheel 5. Spring 15 supplies the described common pawl action. The nose/notch feature permits disengagement, while tongue 24 provides a compliant rotor-pivot support. Plate 31 makes the rocker assembly removable. These are separate functional decisions within one winding system. 2

What the evidence shows

The original patent establishes a disclosed construction with a named inventor. Later IWC material documents use of the principle in calibre 8541. Those are different forms of evidence: a patent is not by itself proof of commercial production, while a later production description is not proof that every detail appeared in the earliest embodiment. 23

The document's evidence concerns this cam-and-pawl construction, not a complete survey of all automatic-winding systems. Its service and support features are part of the design comparison, but no quantitative efficiency advantage over every reversing-wheel or bumper system is established by the patent alone. 2

The objectives of shock tolerance and service access are explicit, but the examined text does not supply controlled impact results, friction losses or winding efficiency under defined wrist motion. No numerical performance claim is inferred. Modern ceramic components are also excluded from the historical version. 2

Research limit: Materials, numerical tolerances and test conditions not established.

Why it matters

This contribution is particularly useful for an enthusiast because the motion can be followed through named parts while personal invention credit is independently anchored in a patent record. The contribution is not the mere presence of an automatic rotor, but a particular route from rotor movement to winding. 23

Research limit: Editorial assessment.

The calibre 8541 literature documents the principle in a later IWC implementation. Its service details are retained with that version label. This is more defensible than treating all later movements carrying the Pellaton name as mechanisms designed personally by the historical inventor. 3

What to look for

The patent's part numbers provide a map for a future examination of its drawings: locate cam 17, rocker 10, rollers 27 and pawls 8/9 before following the winding wheel. The text was read, but original drawing pixels were not inspected here, so no image-based claim about exact geometry is made. 2

Research limit: Text-based guide; no original patent-figure inspection.

The contribution

The strongest verified point is personal attribution: IWC names calibre 89 among Pellaton's developments. That separates a real movement contribution from merely working for the manufacturer. The source does not explain which drawings, calculations or components he personally produced. 1

Pellaton's 1944 appointment is a career milestone, not automatically the movement's launch date. Search results suggested later development and production dates, but no adequate original technical record was opened to resolve those stages in this batch. 1

Research limit: Exact conception, first manufacture and launch dates remain null.

What the evidence shows

A named historical movement and a named developer are established by IWC's chronology. This contribution is retained as partial research rather than inflated with detailed specifications taken from later chronographs. 1

The numbering creates a practical research hazard. Material labelled with later 89-series chronographs is not evidence for the historical calibre 89. Movement identity must be confirmed before a specification, photograph or operating explanation is attached. 1

Why it matters

Within Pellaton's career, a separately credited movement is a distinct contribution from the automatic-winding mechanism. Its precise technical importance and production influence require deeper original-document work than was achieved here. 1

Research limit: Provisional editorial selection, not a completed technical dossier.