cork borer sharpener

I was at a tool auction this weekend and picked this item up. After it was sold , many fellow collectors asked what it was used for. I thought that you might like to see it and it's use.
The conical handled tool is used to sharpen cork boring punches.
In the first photo, I show the entire tool . The second photo shows the conical tapered end with the blade and the slit that the blade slips into. The third photo shows the sharpening tool and a 3/4" cork borer (cork borers are used to bore holes into cork for laboratory purposes. They also make great gasket cutters when twisted on gasket material).
The fourth photo is the cork borer sharpener inserted into the cork borer in a manor that visualizes how the blade, when pressed against the borer's cutting edge will sharpen it when rotated ....hotairfan