As a belated aside...
Both shallow and deep sockets are shown on the patent drawing. In addition, the inventor describes both a version with the socket permanently attached, and a version with a removable socket attached with a knurled screw. The inventor also describes attachments other than sockets being possible, such as a screwdriver bit, or a tap or a drill...
A T-handle is also shown...
So...don't be surprised if more variations on this thing turn up....