Binding device and method of binding

Binding device wherein a support structure (2) houses a pack of sheets provided with through-holes (133) aligned along a rectilinear edge of the pack. The structure moreover carries a binding member comprising a flat sheet-like rectangular member (100) showing, along a side thereof (100a), a plurality of flexible tongues (107) arranged combwise and a closure member (110) extending along the side (100a). The binding device is provided with a bending wall (70) mobile with respect to the pack and adapted to realize the bending of tongues portions projecting from the pack on an end flat member forming a first face of the same pack. A pressing device (90) further realizes bending of the closure member (110) to arrange the closure member (110) on bent tongues (107) and on the end flat member (130b) thereby forming a bound fascicle.