Device for gleichmaessigen load of by a gap ndem material arguing

摘要

1,160,762. Rolling and laminating between ferromagnetic rollers. E. I. DU PONT DE NEMOURS & CO. 7 June, 1966 [10 June, 1965], No. 25259/66. Headings B5A and B5N. [Also in Divisions B6, B8, D1 and F2] Apparatus for applying a uniform pressure to the full width of a running length of material comprises two ferromagnetic members urged together magnetically; one or each of the members is a roller and one or each of them is movable relatively to the other. The material may be a paper, rubber or textile sheet or web, or a yarn; the magnets may be permanent or electromagnets in which the coils may be cooled; the members may emboss the material; the members may be heated or cooled; one member may be a roller and one a platen, or a belt trained over rollers to provide two nips in sequence; and when the members are both rollers the trunnions 13, Fig. 3, of the lower one may be movable on slots 15 in a support 14. In the forms described, the material treated is a web which may enter and leave the nip along vertical or horizontal paths. When the web takes a vertical path, 20SP1/SP, Fig. 3, the rollers are magnetized by an electric coil 6 which surrounds the nip. The lower roller may be initially raised hydraulically until enough magnetism is developed to offset the weight of the lower roller. This form may be adapted for a web travelling horizontally by canting the coil, or by replacing the coil by two coils 6a, 6b, Fig. 3B, each surrounding one of the rollers. The coil may comprise turns of flat strip 16, Fig. 4, insulated from one another by a continuous layer of polyester film, supported in a channel-shaped ferromagnetic flux guide 21 extending lengthwise of the rollers. When the web travels vertically, there is such a coil on each side of the nip, Fig. 4, not shown; when the web travels horizontally there is a coil, 16a, Fig. 5, on each side of each nip roller, the guides 24, 26 having a gap opposite the nip and an additional movable roller 23 is arranged below, or above and below, Fig. 6, not shown, the nip rollers, the additional rollers being disposed in gaps in the flux guide and serving to complete the magnetic circuit through the guides. Where the web takes a path 20SP1/SP, Fig. 7, encircling the upper roller, a coil 29 is wound around a channel-shaped guide 28 arranged at one side of the nip for a horizontally-travelling web or on both sides for a vertically-travelling web (Fig. 8, not shown). In a form when the web travels horizontally, coils 33, 35, Fig. 9, are are wound on the legs of guides 32, 32SP1/SP of T-section one on each side of each roller, the web passing between the upper and lower guides. To increase the attractive force between the rollers, Fig. 25A, the coils are wound on guides 118, 119 of arcuate section extending lengthwise of the rollers within the area of the nip, the ends of the guides being such as to conform to the curvature of the rollers and to provide a clearance for the passage of the web. This form is modified (Fig. 25B, not shown) by providing two guides on each side of the nip spaced apart for the web to travel horizontally between them. To ensure a prolonged application of pressure, an endless belt 133, Fig. 28A, is used as one of the members, an upper roll bearing on two spaced lower ones 3SP1/SP, 3SP11/SP over which the belt 133 is trained with the help of idlers; a coil is provided on a flux guide 134 within the belt or on either side of the upper roller (Fig. 28B, not shown). In these two arrangements, permanent magnets may replace the guides and coils. In Fig. 19A, the rollers are hollow and rotatably mounted on flux guides 51, 52 the legs of which extend rearwardly and are hinged together at 48. Inside each roller is a number of ring magnets with like poles adjacent, the entire outer surface of each ring being of the same polarity. In a modification of this form, the permanent magnets are replaced by coils on the flux guides (Fig. 20, not shown). In Fig. 29B, the lower member is a platen 145 reciprocated along fixed ways by a crank or a rack-and-pinion. The upper member is a roller movable in supports 141, while the magnetizing effect is produced by guides 143 on which are wound coils 144. The rollers may be covered with elastomeric material or be serrated, grooved or otherwise patterned, the pressure applied may be controlled by a device which senses such factors as the spacing of the rollers thickness, and density. Figs. 13, 14A show an arrangement of upper and lower rollers where means are provided for regulating the pressure applied by the rollers, for lifting the upper one for threading-up, for removing or changing the rollers, for supplying heating or cooling medium to the interior of the rollers, and for removing condensate from the interior of the rollers. The rollers are supported in end-columns 62, 63, Figs. 14A, 14B slotted lengthwise to provide machined ways on which mounting-blocks 79, 80 can move. The lower blocks are secured to the bottom of the columns by removable pins 69; the upper blocks are connected by removable pins 73 to the cylinders of hydraulic lifts 71, (Fig. 11, not shown). The rollers 1, 3 each comprise ferromagnetic tubes with laterally projecting shafts 1b and 3b at each side rotatably mounted in bearings in the blocks 79, 80. The shafts on one side are hollow and are bolted to rotary joints 83 through which the rollers are driven. Inside each roller is a scoop 85a communicating by hinge joints to stationary tubes 85 concentrically arranged within the extensions 1b, 3b where they communicate through the joints 83 with drains &c. the tubes 85 are arranged within insulated tubes 81 allowing annular spaces for the passage of heating or cooling fluid to the interior of the rolls. The fluid is supplied and exhausted by pipes 86, 87 (Fig. 12, not shown) passing through the joints 83. On each side of the rollers are ferromagnetic flux guides 96, Fig. 13, which are of C-section and extend along the length of the rollers. These have upper and lower pole-pieces 100, 101 around which coils 102 are wound. To vary the attraction between the rollers, provision is made for creating a repulsive effect, which may be such as to release completely the pressure erected by the top roll. To cool the coils and flux guides they are enclosed in a housing to which forced air is supplied. (Figs. 15-18, not shown). The upper roller is enclosed in a casing 91, secured to the mounting blocks the lower wings 94 of the casing being hinged at 93. Guide rollers 74, 75 of non-ferromagnetic material are mounted in the columns 62, 63 to the side of and slightly above the upper roller, the web 20SP1/SP taking the path shown over these rollers around the casing to the nip. When it is desired to lift off the upper roller, the hydraulic lifts 71 are operated.