Patent GB-419165-A (GB)
Title: Improvements in or relating to apparatus for cutting web material into pre-determined lengths
IPC: B26D1/00
Filed: 1933-11-07
Abstract: 419,165. Feeding, cutting, and delivering web material. DUNLOP RUBBER CO., Ltd., 32, Osnaburgh Street, London. Nov. 7, 1933, No. 30901. Convention date, Nov. 9, 1932. [Class 31 (i).] Predetermined lengths are severed from a continuously advanced web of material, e.g. of rubber, and are lifted vertically and then moved laterally on to a support out of the line of the advancing web. In the form shown, a web of material is fed by a belt conveyer 6, driven continuously by a chain 8, on to a second belt conveyer 7, which is driven from the conveyer 6 through a clutch 15 which is periodically engaged and disengaged by means connected to a knife beam 19. The transmission ratio between the drives of the conveyers 6, 7 is so proportioned that the length fed by the belt 6 between two consecutive pauses of the belt 7 corresponds to the length to be cut, so that a festoon is formed between the conveyers 6, 7 which is passed over a festoon roller and is taken up during feeding movement of the belt 7 so that the web is slightly tensioned. A cam 74, Fig. 6, driven from the belt 7 through interchangeable gearing 77, 78 so that the length severed may be controlled, actuates a double piston valve 43 which controls the supply and exhaust of compressed air from a pipe 53 to a cylinder 41, the piston rod 40 of which is connected by a cable 38 to lever mechanism by which a knife 22 carried on the knife beam 19 may be depressed, against the action of springs 20, to co-operate with a lower knife 23 situated under the web in a loop formed by rollers 25, 26, 27 in path of the conveyer 7. The arrangement is such that starting with the parts in the position of rest, shown in Figs. 2, 3, with the knife 19 in the raised position and with the clutch 15 engaged by linkage actuated by the upward movement of the knife beam 19, the conveyer 7 is driven to advance the web under the knife. The cam 74 controls the valve 43 to depress the lower piston valve 46 into its lowermost position, against the action of a spring 63, where it is engaged by a spring-held pin 58 connected with a pivoted trigger lever 71. As the upper piston 45 rises, under the action of the spring 50, the supply-pipe 53 is placed in connection, by a byepass 55, with the pipe 42 which leads to the cylinder 41, so that the knife beam 19 is lowered against springs 20, and actuates a connecting-rod 31 by a lever-arm 29 connected to it to turn a control shaft 17 and disengage the clutch 15. As the clutch is disengaged, a connecting rod 68 is pulled upwards to tilt a tubular sleeve 67 about a pivot and cause a ball 70 therein to roll to the opposite end and tilt the trigger lever 71 to release the lower piston 46 to rise and cut off the supply of compressed air to the cylinder 41 and open this cylinder to atmosphere by a duct 65. The knife beam 19 then rises for a further sequence of operations. The piece severed is lifted from the conveyer belt 7 by suction cups 97 connected to a pipe 96 carried on horizontal arms 80, 81 above the main frame 1 and pivoted on vertical axes. The pivots 94, 95 carrying the pipe 96 are movable vertically in the arms 80, 81 under the action of springs 105, 106, and are raised and lowered by means controlled from the knife beam 19. When the knife beam is lowered, the cups 97 are connected to a suction pipe 110 through a double piston valve 109 and, as the knife beam returns, the pipe 96, together with the severed length of material, is raised by the springs 105, 106. When the clutch 15 is engaged, a shaft 87, driving a chain 89 coupling the arms 80, 81, is rotated by rack and pinion gearing to swing these arms, as indicated by the arrows in Fig. 2, to move the severed length over a carriage 112 movable on a support 111. In the outermost position of the arms 80, 81, the valve 109, which is actuated by a cam 126 mounted on the same shaft 75 as the cam 74, which controls the valve 43, shuts off the suction pipe 110 and connects the pressure pipe 53 to the suction cups 97 to release the severed length on to the carriage. The arms 80, 81 are then returned to position over the conveyer belt 7 and the pressure pipe 53 is shut off. The rolling ball arrangement 70 allows a period of rest of the machine in which the suction cups 97 cling to the web of material before the suction device is raised. A cooling- water sprinkling device 132 may be arranged above the conveyer belt 7 if such follows calender rolls, and excess water may be blown off by a pipe 133 connected to the pipe 53. The belt 7 may be similarly cooled.