Patent ID: 7484641

Claim:
A closable opening device for a sealed package of a pourable food product, said device comprising: a frame fitted about a pierceable portion of said package and defining a through hole; a removable threaded cap which screws onto said frame to close said hole; a tubular cutting member engaging said hole and having an end cutting edge which cooperates with said pierceable portion to unseal said package; first connecting means for connecting said cap and said cutting member so as to rotate said cutting member during rotation of the cap to unscrew the cap off said frame when unsealing said package; and second connecting means for connecting said frame and said cutting member so as to move said cutting member along a spiral path through said pierceable portion in response to said rotation of said cap; wherein said cutting edge comprises a main blade; and at least a number of first teeth which, proceeding along said cutting edge in the opposite direction to the direction of rotation of said cutting member, are located downstream from the main blade; said first teeth decreasing gradually in height so as to act successively on said pierceable portion; wherein said cutting edge comprises a number of second teeth located on the opposite side of said first teeth to said main blade, and said second teeth are all the same height and are at most equal to the minimum height of said first teeth.