Creasing device for forming creases in paper and bookbinding articles, and machine comprising such device

A creasing device for forming creases in paper and bookbinding articles, said device comprising:

• a frame with a substantially horizontal support surface for supporting an article to be creased and feeding it in a substantially longitudinal direction;
• a stationary tool and a movable tool, reciprocally facing one another and placed on opposite sides of said support surface, wherein the stationary tool comprises a central stationary member integral with said frame and at least one lateral displaceable member whose position can be adjusted in height relative to said central stationary member,
• each of said movable tool and said stationary tool having at least one elongated punch and at least one elongated recess, which are located in longitudinally offset positions;
• first actuator means acting upon said movable tool to move it toward said stationary tool and interact with the opposite faces of the article, to form a crease;
• second actuator means acting upon said said at least one lateral displaceable member for selectively moving it between a first end position in which it is designed to interact with said movable tool and a second end position in which it cannot interact with said movable tool;
• guide means associated with said stationary tool to guide said at least one lateral displaceable member between said first end position and said second end position;
• said guide means defining a curvilinear path contained in a plane substantially perpendicular to said support surface and said longitudinal direction, said guide means comprising a cam consisting of at least one slot formed on one of said members and at least one pin associated with the other of said members for slidably insertion in said at least one slot, said at least one slot comprising a substantially horizontal first portion and a substantially sloped down second portion which is inclined relative to the horizontal, the portions defining respective sections of said curvilinear path,
• said central stationary member and said at least one lateral displaceable member being substantially vertical elongate rectangular plates in mutual sliding contact relationship, said at least one slot being formed on said at least one lateral displaceable member and said at least one pin being associated with said central stationary member,
• said central stationary member having a median punch, said at least one lateral displaceable member being one of two lateral displaceable members each having a side recess, said movable tool having a median recess and a pair of lateral punches facing the median punch and the side recesses of said stationary tool respectively.