Can flanger having base pad with stop spacer arrangement determining a

Abstract

A flanging apparatus includes a flanging head assembly having a cluster of freely rotatable spin flanging rollers and a stop ring against which the flange hits during the final flange forming stages to limit the flange to a specific diameter. To prevent the flange from entering the crack formed between the rotating roller and the stationary stop ring, there is provided a step spacing the stop ring surface from the roller forming surface. The forming process occurs as a result of spring biased relative axial movement of the can open end toward the forming surfaces, caused by contact between the can bottom with a base pad movable in a working stroke toward the flanging rollers with a cam controlled spindle. A spring extends between the base pad and a base pad spring collar attached to the spindle to create a predetermined spring force which is normally applied throughout the flange forming process. However, in the event that the predetermined spring force is insufficient to ensure full contact of the can open end with the complete flange forming surface, a gap formed between the base pad spring collar and the base pad is operable to close so that the force now urging the can open end against the stop surface and the flange forming surfaces is greater than the predetermined spring force. As the can open end is deformed to a sufficient extent, the predetermined spring force once again overcomes the axial resistance of the can so as to complete the flange forming process.