I stole the lens and shutter for my speed graphic. The shutter is a bit weird because it has no cocking lever or release trigger either. It seems to only work with a cable release, and then it works like a double-action revolver...pressing the cable release both cocks and fires the shutter. The problem I have is my shutter release doesn't seem to stick out far enough to trip the shutter. It works fine if you stick a paperclip in there, though. Then again my shutter release isn't the best. Do you need a special cable release for these things?
Regarding the shutter release: I also have a Polaroid MP-3 Land Camera/Multi-purpose Industrial View Camera, but with a 127/4.7 Rodenstock-Ysaron lens in a Prontor shutter. There are two cable releases, one for opening & closing the diaphragm and the other operates the shutter. On the MP-3 you push a lever at the top right to cock the shutter. At that point the end of the shutter release cable extends and stays at, according to my measurement, 17mm. When the operator is ready to take the photo, the round shutter release button at the front of the unit is pushed and presto! The shutter releases.
Now, if you attach a conventional shutter release cable (not connected to the MP-3) to the lens and slowly push the cable in until you hear a slight 'click', the shutter is charged. Push the cable further and the shutter is released.
I have not used the Ysaron lens yet but have read that it is a Tessar design and has (for 4x5), ".....10 or 12mm left for movements." It also may have rare earth elements. Mine was manufactured between 1961-'66 according to the serial number.
Sorry, I'm getting off-track here as this isn't the lens you have, but, the coverage may be the same for both lenses. I'll have to do some testing myself.
Hope that helps.
-Marc