I have a 1922 V-C catalog with the same drawing of the Helice system. Somewhere--although I can't find it now--I remember reading that V-C had brought suit against one or two other gunmakers who had copied the Helice system. According to the 1922 catalog, the patent on the Helice system dates from 1907.
As far as I know, "Helice" isn't the name of a V-C employee who developed the locking mechanism, but is simply a descriptive term for it. It's the French word for screw or spiral. Webley already had a "screw grip" bolting system in place by that time, but it's clear from the drawing that the Helice system is a somewhat modified version of the same concept.
The 1922 catalog is also the one that includes a full page photo of French ace of aces (and surviving ace of aces of all nations from WWI) Rene Fonck, in which he praises his Helice Grip shotgun. "The birds fall like Krauts!" Great ad!
