An expanding machine includes a chassis, a feeding roller carrying a honeycomb paper, a guiding roller, and an expansion roller assembly including an upper expansion roller, a lower expansion roller, and a passage gap. The upper expansion roller includes upper projection assemblies that are staggered with respect to each other. Each of the projecting assemblies includes upper projecting portions and upper supporting portions that are alternate with respect to each other. The lower expansion roller includes projecting portions and supporting portions corresponding to the upper expansion roller. When the expansion roller assembly is put into rotation, the upper projecting portions correspond to the lower supporting portion, and the lower projecting portions correspond to the upper supporting portions, so that the projections that are separately arranged may pull and expand the honeycomb paper, making it not readily compress down the honeycomb paper or generating apparent compressing marking.

An expanding machine includes a chassis, a feeding roller carrying a honeycomb paper, a guiding roller, and an expansion roller assembly including an upper expansion roller, a lower expansion roller, and a passage gap. The upper expansion roller includes upper projection assemblies that are staggered with respect to each other. Each of the projecting assemblies includes upper projecting portions and upper supporting portions that are alternate with respect to each other. The lower expansion roller includes projecting portions and supporting portions corresponding to the upper expansion roller. When the expansion roller assembly is put into rotation, the upper projecting portions correspond to the lower supporting portion, and the lower projecting portions correspond to the upper supporting portions, so that the projections that are separately arranged may pull and expand the honeycomb paper, making it not readily compress down the honeycomb paper or generating apparent compressing marking.