Food can crimping head including means for taking up slack

A crimping head for sealing food cans by crimping a lid on a can body, the lid having an edge and the can body having an outline and having an edge, the head comprising at least one crimping roller mounted on a moving support piece that causes said crimping roller to move in a plane parallel to a work plane on which the can body to be crimped stands, so as to follow a path such that said crimping roller follows exactly the outline of the can body while remaining pressed thereagainst so as to crimp the edge of the lid onto the edge of the can body, a guide connected to said support piece to constrain said roller to follow said path, said guide comprising a first rotary wheel having an axis perpendicular to said work plane, and said guide further comprising a cylindrical cam surface having generator lines perpendicular to said work plane, said generator lines following an appropriate outline that extends parallel to said work plane, said wheel running against said cam surface, a holding assembly connected to said wheel to hold said wheel in contact with said cam surface, said holding assembly comprising a second rotary wheel juxtaposed with said first wheel, such that both rotary wheels rotate about said axis, said second wheel having a bulging peripheral surface having a section in a radial plane, which section is a curved line convex toward the outside, and said holding assembly further comprising a counter-cam surface situated facing said cam surface, said counter-cam surface comprising a bearing and running surface for said second wheel, said counter-cam surface extending parallel to said cam surface while being inclined at a small angle relative to the direction of said axis of said two wheels, the relative position along the direction of said axis between said second wheel and said counter-cam surface being adjustable so as to make it possible to adjust the slack between the assembly of said two wheels and said facing cam and counter-cam surfaces between which said assembly of said two wheels is interposed.