| CPC B26F 1/22 (2013.01) | 23 Claims |

|
1. A knife for a cutting apparatus to obtain incision lines and cuts on a capsule made of plastics intended to close a container, said knife being suitable for performing cuts and incisions on a side wall of said capsule when said capsule is around a rotation axis (R) and moved along a path to interact with said knife in an advancement direction, said knife including a plurality of separate cutting tools arranged in a layered structure, in which said cutting tools are parallel to a plane and stacked in the direction of a vertical axis orthogonal to said plane, said layered structure of cutting tools including:
a first horizontal cutting tool arranged for performing circumferential cuts on said side wall at a first height on said vertical axis to define a tamper ring in said capsule;
a second horizontal cutting tool, arranged for performing further circumferential cuts on said side wall at a second height different from said first height on said vertical axis; and
a third cutting tool, arranged for performing oblique cuts on said side wall and for defining with said second horizontal cutting tool and with said first horizontal cutting tool connecting portions connecting said tamper ring and said side wall;
wherein said third cutting tool includes at least two tilted cutting edges having a tilt different from each other relative to a reference plane passing through said vertical axis and tangent to said advancement direction of said capsule, said third cutting tool being interposed between said first horizontal cutting tool and said second horizontal cutting tool, whereby said third cutting tool may be disassembled from said layered structure in order to be replaced with a different third cutting tool to obtain a different shape of said connecting portions.
|