Creasing device for corrugated board sheet and corrugated-box making machine
View Patent ↗A slotter-creaser unit includes an upper creasing head and a lower creasing head. A protruding portion is arranged on a periphery of the lower creasing head in a circumferential direction. A first pressing portion and a second pressing portion having different lengths and different curvature radiuses in a width direction are arranged opposite to each other across the protruding portion and in an alternate manner in the circumferential direction.
1. A creasing device that forms a crease on a corrugated board sheet along a flute of a fluted inner sheet between linerboards of the corrugated board sheet, the creasing device comprising:
a creasing roll having:
a protruding portion corresponding to a center position of the crease and arranged on a periphery of the creasing roll in a circumferential direction;
a pressing portion arranged on both sides of the protruding portion in a width direction with respect to the creasing roll, wherein the pressing portion includes a first pressing portion and a second pressing portion having different lengths in the width direction and arranged opposite to each other across the protruding portion and in an alternate manner in the circumferential direction;
a body having a first attaching portion and a second attaching portion arranged opposite to each other across the protruding portion and fixed to a rotatable shaft;
a first pressing piece having the first pressing portion and to be fixed to the first attaching portion; and
a second pressing piece having the second pressing portion and to be fixed to the second attaching portion.
2. The creasing device according to claim 1 , wherein
the body is evenly divided into two parts in the circumferential direction, and
the pressing portion is divided into a plurality of parts in the circumferential direction to alternately arrange the first pressing piece and the second pressing piece.
3. The creasing device according to claim 1 , wherein the first pressing portion and the second pressing portion are arranged along with a length of the corrugated board sheet on the periphery of the creasing roll.