Printer for printing information on center-folding type book in open

Abstract

A printer is used for printing information on a center-folding type book when the book is in the open state, and comprises a printing head, a platen movable toward and away from the printing head, and feed rollers for moving the opened book through the printing position defined by the printing head and the platen, such that the printing operation is carried out on a leading half of the book and then on a trailing half thereof. A gap between the printing head and the platen is adjusted in response to a variation of a thickness of the half of the book positioned at the printing position; this adjustment being carried out by abutting the platen against the half of the book, and then moving the platen away therefrom by a given distance, before the printing operation is carried out on a first line contained in the trailing half of the book and closest to a center-holding line thereof. The book is then further moved so that the first line is moved away from the printing position, to carry out a proper adjustment of the gap with respect to the trailing half of the opened book.