| 摘要 |
1,202,772. Feeding webs. SCHNELLPRESSENFABRIK KOENIG & BAUER A.G. 5 Jan., 1968 [11 Feb., 1967], No. 792/68. Heading B8R. In a web-roll changing mechanism of generally known construction in a rotary printing press, means are provided whereby when the difference between the square roots of the angular speeds of a web-engaging press-cylinder and the expiring roll 3 reaches a predetermined value a pulse is generated which produces signals causing simultaneous reduction of the press speed and initiation of a web-roll changing and splicing operation. A measuring motor generator 8 is driven from the press through a change-speed gearing 7, and another measuring motor generator 9 is driven from the core of the expiring roll 3 the rotary speed of which is dependent on the roll diameter. The generators are connected in opposition, and cause the impulse to be generated when the speeds of the press cylinder and roll 3 are such that the difference between the square roots reaches a a, predetermined value. The comparison between the square roots of the speeds of the generators may be effected by any suitable device that performs the required mathematical operation. A belt 4 for rotating the replacement roll up to the required speed is also driven from the press via the change-speed gear 7. Specification 986,082 is referred to. |
