Improvements in or relating to apparatus for corrugating paper or cardboard

722,923. Corrugating paper &c. AKT.-GES. DER MASCHINENFABRIK VON T. BELL & CIE. April 16, 1952 [April 17, 1951; June 27, 1951], No. 9606/52. Class 141. Apparatus for corrugating paper or cardboard, particularly for subsequent assembly with transversely corrugated paper or cardboard, by producing one longitudinal corrugation after another in a continuous run of material, comprises a stationary plate having longitudinal parallel grooves and a plurality of rigid forming members mounted in a support in a forwardly pointing wedge pattern, each forming member engaging one of the grooves of the plate to press the material into the groove. As shown in Fig. 1, grooving rollers 3 mounted on shafts 2 above the plate 1 form successive corrugations on either side of the centre of the paper &c. fed between them and the plate in the direction of the arrow. The plate 1 is heated and the rollers 3 are laterally displaceable on the shafts 2. In another embodiment, Fig. 7, grooving shoes 7 mounted on a frame 6. in a V-shaped pattern, replace the rollers, means comprising an intermediate member mounted in a guide slot being provided for their lateral displacement. The support 6 is mounted on a shaft 13 and provided with a pair of toothed segments 14 each engaged by a gear wheel 15 so that it may be swung up and down when a new run of paper is introduced. In a modification, Fig. 10, the frame comprises several parts 16, 17, 18, 19 rotatable about connecting shafts 20 and each carrying five or six pairs of shoes. The parts 16 to 19 are successively brought into operation by means of an electric motor 23 driving a spindle 22 having a threaded portion 22a engaged by a nut 21 carried on an arm 21a secured to the part 19, abutments causing adjacent parts to move in unison about successive shafts 20. Top and bottom driving rollers 24, 24a are provided for advancing the paper. In an alternative construction, parallel staves may form the grooved surfaces on the bottom plate, the staves co-operating with grooving shoes and being mounted with their front ends in staggered relation. Alternatively, a grooved bottom plate may co-operate with grooving shoes, the central shoe having a symmetrical profile gradually assuming a V-shape before the other grooving shoes are reached. These are initially tapered to apply pressure to the inner side of the corresponding groove and gradually assume a V-shape. In the apparatus shown in Fig. 13, the tops of heatable boxes 26 provide the grooved plate. Grooving rollers 3 are mounted in a housing 28 reciprocated along a guide rail 29 by means of a link rod 31 and disc 30 rotated by a motor. Seizing sleeves are provided on both the plate and housing to advance the paper stepwise as the corrugations are formed. The corrugated paper may be glued to further layers 32, 35 by means of rollers 34, 37 respectively.