Patent GB-1429445-A (GB)
Title: Method for wrapping elongate cylindrical objects
IPC: B65B41/16
Filed: 1974-05-01
Abstract: 1429445 Wrapping elongate cylindrical objects HUNT & MOSCROP Ltd 1 May 1974 [14 May 1973] 19046/74 Heading B8C A method of covering a cylindrical object, such as a carpet roll 20, with elongate sheet material F having a width less than the length of said object, comprises the steps of rotating the object; feeding the sheet F and wrapping it around one end portion of the object while guiding the sheet F at right angles to the rotational axis of the object to provide at least one convolute winding around said one end portion of the object; feeding the sheet F to, and wrapping it around, the medial portion of the object while guiding the sheet in angular relationship to the rotational axis of the object to provide spiral windings around the medial portion of the object; feeding the sheet F to, and wrapping it around, the other end of the object while guiding the sheet at a right angle to the rotational axis of the object to provide at least one convolute winding around the other end portion of the object; and cutting the sheet of material after it has been wrapped around the object. As shown, the roll 20 is supported on a pair of rollers 18, 19 which are rotatably mounted in bearing blocks 16, 18 on a frame mounted on rollers 11 and which are driven by a variable-speed electric motor 21 and drive belts 22, 24, 26, 27, Fig. 13. Conveyer rollers 31 are mounted in a frame 30 which can be raised from a lowered position, Fig. 4, by pneumatic cylinders 32 to support the roll 20 so that it can be initially positioned correctly between the rollers 18, 19 and then finally moved axially into a heat-shrink tunnel 40, Fig. 1. A roll 42 of thermoplastic sheet material F is supported on a pair of rubber-covered rollers 52, 53 rotatably supported between the end walls 50, 51 of a plate 45 which is pivoted, at 46, between its ends, to a carriage support plate 47. The film F, fed from the roll 42 which is positioned between adjustable collars 54, 55 on the roller 52, passes between nip rollers 56, 57 to the roll 20, the nip-roller 56 being controlled by an adjustable electromagnetic brake to adjust the tension of the film F. The carriage 47, which carries a hot-wire film cutter 63, actuated by a motor cylinder 72 through links 70, 65, is movable along rods 77, 78 parallel to the rollers 18, 19 by a chain 85 which is driven by a reversible variable-speed electric motor 83. Limit switches 95, 96, Fig. 2, control the extent of traverse of the carriage. The angular position of the pivot plate 45 with respect to the plate 47 is controlled by a reversible electric motor 92 which drives a gear 91 which engages in an arcuate array of holes 90 in the support plate 47. Limit switches 93, 94 regulate the arcuate movement of the plate 45. Film-shrinking air heaters 105, 106, Fig. 14, carried by the end walls 50, 51 of the carriage 47, are adapted to heat the sheet F at the ends of the roll 20 where excess film tends to be formed as a winding is changed from convolute to spiral form, and vice versa. After cutting the ends of the film F are folded inwardly. A double wrap may be formed on the medial portion of the roll by rotating the pivot plate 45 to the position shown in Fig. 12, and moving the carriage back down the track rods 77, 78 to the other end of the roll where one, or more, convolute windings are again formed before the film is cut. Varying degrees of coverage of the object may be obtained by changing the speed of travel of the carriage 47 and the angle at which it is set to the rotating object 20.