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Elgin Grade 303, The Winding/Setting Clutch Mechanism

Here are a few shots showing the winding/setting clutch in a typical American pocket watch, an Elgin 12 size in this instance, a grade 303.

The first images show the normal position, at rest.  The mechanism has a spring that has pushed it into winding mode.  Node that the clutch is pushed upward, engaged with the minute wheel just below the center of the movement.  In this mode, turning the stem turns the minute wheel, and thus the hands.  The hands slip on the center shaft when this happens.

The watch case has a square arbor that engages the mechanism. It snaps in and out on a spring inside the neck of the case. The spring holds the arbor pushed in, pushing the arbor into winding mode.
In the last image that shows the movement in the case, look closely at the clutch. The arbor, now pushed in, actuates a lever that pushed the clutch down, off the minute wheel, and engaged with the winding pinion at the lower edge of the movement.

The clutch moves in the opposite direction from that of the arbor in the case.  That is, when the crown is push inward, the clutch lever presses the clutch down against the winding pinion.  When it does this it is working against the spring in the watch that wants to hold the clutch against the minute wheel

Problems develop if the spring in the case neck, called a sleeve, is broken or not strong enough to hold the arbor inward against the spring in the movement, or if the arbor in the case does not go into the movement far enough, or too far, for the clutch to fully engage in both modes.

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