Patent GB-183413-A (GB)
Title: Improvements in means for controlling the feed of a web to cutting or other apparatus
IPC: B65H23/18
Filed: 1921-09-21
Abstract: 183,413. Union Bag & Paper Corporation, (Assignees of Avery, T. M.). July 22, 1921, [Convention date]. Feeding and registering webs. - Mechanism for registering a travelling web with a cutting or other device acting periodically upon it comprises a rotary member driven at a constant speed relatively to the cutter &c., a rotary member driven by the web, and means actuated upon relative rotation between the members to increase or diminish the speed of the web relatively to the cutter &c. The invention is described in its application to a machine for making paper bags from a web bearing printed impressions, but may be applied to other machines such as multi-colour printing-machines and machines for trimming the edges of wall-paper. The shaft 11, Fig. 4, of one of the feed-rolls 5 is driven from the main shaft of the machine by a gear 17 in engagement with a gear 18 fixed to a member 21 loose on the shaft 11 and provided with internal gear teeth 22 meshing with pinions 23 engaging a gear 28 fast on the shaft 11, the pinions 23 being carried by a worm-wheel 25 loose on the shaft 11 and in mesh with a worm 20 on a shaft 30 driven by a reversible electric motor 35. While the worm wheel 25 is stationary, the feed-rollers are driven at a constant speed, but when it is rotated, the feed-rollers are accelerated or retarded according to the direction of rotation of the motor 35. This motor is started when a detector roller 37, Figs. 9 and 14. loose upon its shaft 36 and driven by the passage of the web over it, moves at a different speed from its shaft 36 which is driven by and at the same speed as the web cutting or breaking device 6<a>, Fig. 4. A ring member 45 mounted on a ball bearing sleeve 39 fixed to the shaft 36 is provided with pins 46 which are operatively engaged by perforations formed in a margin of the web at definite positions relatively to the printed impressions so that the member 45 is driven at the same speed as the web. An electric contact 55 carried bv the ring 45 projects into a gap 54 between the ends of a pair of segmental contact members 52, 53 and these members 52, 53 and a pair of collector rings 59, 60 are clamped in grooves between insulating rings 47 - 50 keyed to the sleeve 39. The contacts 52, 53 are electrically connected to the rings 59, 60 respectively by spring-pressed pins mounted in holes in the insulating rings and the rings 59, 60 are connected to brushes 82, 83 and leads 117, 116 to electromagnets 99, 98 connected through a lead 115, battery B and switch S to the machine frame and thus to the switch 55. The armatures 103, 102 of the magnets are connected to the live wire 111 and the leads 109, 110 to the motor 35. If the web is being fed too rapidly the contact 55 engages the contact 53 closing the relay circuit through the magnet 98 which thereupon closes the motor circuit 111, 110, 114 to drive the motor 35 in a direction to retard the rotation of the feed rollers, but if the web lags, the contact 55 engages the contact 52 and the relay circuit is closed through the magnet 99 and the motor 35 is driven in the opposite direction through the circuit 111, 109, 114 to accelerate the feed. The contact 55 is yieldingly supported, as shown in Fig. 13, being mounted on a roller 65 hung on a shaft 66 in a bracket 67 fixed to the ring 45, and held in the median position by a spring 68. To allow of initial adjustment of the shaft 36 of the detector roller relative to the cutting &c. mechanism, a clutch 77 is provided between it and its driving- pinion 76 as shown in Fig. 9.