Apparatus for applying adhesive to the outside surfaces of a book block to be encased in a book casing inside a casing-in machine

An apparatus for applying adhesive to outside surfaces of book blocks to be encased in casings inside a casing-in machine, each book block including a fold region, the apparatus comprising:

• a circulating conveyor including saddle plates on which a respective one of the book blocks is to be conveyed;
• an adhesive application device including two application rollers arranged opposite each other in an adhesive-application region, thereby allowing each application roller to roll off one outside surface of a book block that is conveyed on a saddle plate, the application rollers having parallel rotational axes, each application roller including a recess that presents a shoulder parallel to the rotational axis of the roller and adapted to apply adhesive to the fold region of a book block, wherein the application rollers are mounted so that a rotational position of each application roller is adjustable and changeable based on a position of a specific fold of the book block that passes through the adhesive application region, and wherein the conveyor has a movement that is synchronized with the rotational movement of the application rollers;
• separate drives coupled to the application rollers and the circulating conveyor for an infinitely variable change in the relative position between the saddle plates on the conveyor and the rotational position of the application rollers;
• a carriage mounting the two application rollers and being moveable in a direction transverse to the rotational axes of the drive shafts of the application rollers, wherein the separate drive for the application rollers includes a drive motor mounted on the carriage and an angle gear including a conical wheel having a rotation axis arranged parallel to the displacement direction of the carriage and connected to the drive motor;
• and
• a joint control unit connected to and controlling the separate drives, wherein at least the drive for the application rollers comprises a controllable drive element.