Patent GB-482819-A (GB)
Title: Horizontal press roll assembly for paper making machines
IPC: D21F3/06
Filed: 1936-08-05
Abstract: 482,819. Press roll assemblies. BELOIT IRON WORKS. Aug. 5, 1936, No. 21578 Convention date, May 18. [Class 96] Water is extracted from wet sheets of paper in a press roll assembly having three rolls, the outer two being urged towards the centre one to create nip pressure therebetween, and the axes of the rolls being maintained in substantially the same horizontal plane to preserve uniform nip pressures irrespective of vertical deflection of the rollers ; the wet sheet being passed through one nip, the squeezed out water being sucked from the nip, around the centre roll and through the other nip. The squeezed out water falls free of the web during its upward passage through one of the nips. The web W is delivered from a forming wire 10 trained around a suction couch roll 11 under a guide roll 13 to a conveyer felt 14 which carries it over a suction roll 17 and through the nip between this roll and centre roll 19. The web then passes around the bottom portion of roll 19 and together with a felt 20 passes through the nip between roll 19 and a suction or plain roll 12a. The web then passes in a guide roll 23 to a series of drying drums. The centre roll 19 has a wiper 33, which may be pivotally mounted, to keep it clean. If the third roll is a suction roll the suction may be in advance of the nip so that water is sucked from the felt 20 before it contacts with the web W. The centre roll is rotatably mounted on a stand 25 to which the member or members carrying one or both of the outer rolls is or are pivoted. One bearing housing 48, Fig. 3, for the suction roll 17 has a suction manifold 50, extending therethrough to communicate with the suction head 51 of the roll, and supported on a member 53 pivoted to the base of the assembly. A flexible pipe connects this manifold with a vacuum pipe. A pan 58 beneath the roll collects water dripping from the felt and roll. A similar pan 73 catches water from the second nip. Feet 59, 72 prevent the roll frames from swinging too far about their pivots 54, 71. Yoked arms 62, 63 extend upwardly from the bearing housing of the centre roll, and arms 75, 76 extend upwardly from bearing housings 48 and 69 respectively. Arms 62, 63 receive pivot pins 79 passing through the apertured ends of rods 81 which extend between fingers on the ends of arms 75, 76 and through bosses 82 which are slidable on the rods and have notched portions 83 fitting into grooves 78 in the fingers of arms 75, 76. The ends of rods 81 are screwed into gears rotatable by hand wheels 89. Coiled springs 90 between gear housings 84 and bosses 82 surround the rods 81 and urge the outer rolls against the centre one by an amount which is adjustable by hand wheels 89. Indicating devices give the amount of compression of springs 90. If desired a marking or smoothing roll 61a can act on the web W as it passes round the centre roll. The centre roll may be driven from a motor which also drives the couch roll, the end rolls being driven by frictional contact with the centre roll, or the two end rolls may be driven by the motor, and the centre one by friction. Universal joints used in the driving shafts for the rolls permit them to be tilted without interference with their driving connections. The centre roll may be rubber covered, or may be of metal, stone or composition material. The side rolls may also be rubber covered. The press roll assembly can be placed near the couch roll, avoiding a long draw of the wet web, and since the web is separated from the felts immediately after passage through a nip, it does not re - absorb moisture from the felts. The rollers do not need to be highly crowned. The felts are not subjected to reverse bends.