I could not find the exact reference for the chronograph movement pictured on this page, but I believe it is part of the Landeron 48 family.
2-register chronograph
Hands removed
Full movement
Top half of the movement in more detail
Bottom half of the movement in more detail
Movement with chronograph function running
Movement with chronograph function stopped
Movement in return to zero position
Operating lever and cam
The hammer is not separate from the cam
The operating lever is controlled by a this pusher
I could not removed the screw attaching the lever and intermediate driving wheel
The driving wheel sits on top of the fourth wheel of the base movement
The chronograph seconds wheel sits on top of the centre wheel of the base movement
