Window crank parts
A landlord from New Hope, MN says:
May 2, 2016
It is a getty crank. Its a very old window. 9inch arm and chain like mechanism attatched to crank that jams after you open the window more the 3-4 inches. When it jams, the person on the outside (of the house) has to push the window while the person inside the house cranks the handle.
Dave from SWISCO responded:
May 3, 2016
We do carry the gear for this old Getty chain type operator, but not the complete operator. I don't believe it is still available. Your operator kind of reminds me of our 39-379. I'm not sure if you could use that as a replacement, but it would likely require extensive adaptation of your window. Most manufactures today use a type of operator like the 39-083. Take a look and see if you can adapt that to your window, as well. You may want the help of a local professional.