From a 1915 issue of Popular Mechanics:
CORK EXTRACTOR (FIG. 9)—This extractor has a pointed shank, on one side of which is a slot. Mounted in this slot is a pivoted bar which lies flush with the shank when it is being thrust into the cork but swings outward and engages the cork when the shank is pulled upward.
That would be Harry Beckley’s patent of 1915 (#1,149,112) for his Cork Extractor.
Beckley’s patent description reads:
The invention relates to cork extractors and the principal object of the invention is to provide a device of this character having a pivoted bridging bar which is slidably mounted upon the shank and so constructed that it will be automatically thrown to operative, engaging position as an attempt is made to withdraw the pin or shank from the cork.
If you have a spiked cork extractor that has “….a pivoted bridging bar which is slidably mounted upon the shank,” I would be interested
josef@vintagecorkscrews.com corkscrewing around 