Cylinder, device and machine for aligning magnetic or magnetizable particles on a web-like or sheet-like substrate

Abstract

A cylinder is usable, in particular, for aligning magnetic of magnetizable particles, which are contained in a coating medium that is applied to a first side of a web-like or a sheet-like substrate, which cylinder, in the region of its outer circumference, has a plurality of elements effecting a magnetic field, magnetic elements for short. The magnetic elements are arranged in or on a plurality of ring elements that are spaced axially apart from one another and that are positionable in the axial direction on a shaft, in or on which ring elements, in turn, a plurality of magnetic elements are respectively arranged one after the other in the circumferential direction. At least two adjacent ring elements, each have a covering element, forming a part of the cylindrical lateral surface of the cylinder and extending in the circumferential direction, at least over the circumferential region populated with magnetic elements. The covering elements of two ring elements adjacent to each other have, on their sides facing each other in the axial direction, a plurality of projections alternating in the circumferential direction with recesses and offset in a circumferential direction in such a way that, during a relative movement of the two ring elements towards each other, the projections on the covering element of one ring element engage, in the manner of teeth, in corresponding recesses of the other ring element, and, as seen in the circumferential direction, can overlap. A security paper printing machine, having such a cylinder, is also disclosed.