Two length wire advancer

This advancer give two advancing lengths (L1 and L2) alternately.
White slider linearly reciprocates thanks to pink input crank and green conrod. Violet part and two blue screws are set to ensure that the wire can move only when the slider is pulled.
When the blue bar is at its lower position, the advancing length is max (L1). The red roller doesn’t touch the blue bar.
When the blue bar is at its upper position, the advancing length is L2, L2 is shorter than L1, because the high portion of the blue bar raises the red roller and make the violet bar do not contact the wire in a part of the slider pulling stroke.
Orange cam receiving rotation from the pink crankshaft controls motion of the blue bar via a chain drive. Its transmission ratio is 2.
Device for keeping the wire immobile (maybe a wire straightener), when it is not pulled, is not shown.
This video is an attempt to decode the advancer of the machine shown at
   • Видео  

STEP files of this video:
http://www.mediafire.com/file/cgte7m0...
Inventor files of this video:
http://www.mediafire.com/file/48z7tc4...