Patent GB-522535-A (GB)
Title: Improvements in or relating to apparatus for joining webs in printing and other machines
IPC: B65H19/18
Filed: 1938-12-14
Abstract: 522,535. Feeding webs. HOLMES & CO., Ltd., J. H., and ANDERSON, W. Dec. 14, 1938, No. 36392. [Class 100 (i)] In a web renewing mechanism for a printing or other machine in which the replacement roll is brought closely adjacent the running web the end of the web of the rotating replacement roll is moved into contact with the running web by a transfer device which rotates with the replacement roll. The running roll A<SP>2</SP>, replacement roll A<SP>1</SP>and reverse roll A', Fig. 1, are carried by end bungs A mounted in rotatable spiders Band one bung of each roll has pivoted upon it a transfer device comprising a frame C, Figs. 1 and 4, to which is pivoted an arm E having a pivoted clamp E<SP>2</SP>to hold the free end of the web of the roll prior to the renewing operation. The arm E is connected by a link E<SP>6</SP>to a lever E<SP>7</SP> pivoted on the frame and having an extending operating finger E'. A roller E' on the end of the lever E' is normally engaged by one arm of a bell-crank lever F held by a spring F<SP>3</SP> in contact with a stop F<SP>4</SP>A slidable pawl C<SP>2</SP> on the frame C co-operates with aratchet wheel C<SP>3</SP> fixed to the bung A and is connected to a toggle device C' having an extending operating finger C<SP>5</SP>and also connected to brake levers D pivoted on the frame C and co-operating with a brake drum D' on the bung. The new roll is prepared by cutting one end at an angle so that its extreme end is at one side of the roll. This end W<SP>5</SP>, Fig. 4 is carried over the clamp E<SP>2</SP>and inserted between a cutting edge on the clamp and a co-operating block E<SP>3</SP>. The pawl C<SP>2</SP> is engaged with the wheel C' and in this position the toggle C<SP>4</SP> holds the brake levers away from the drum D'. The parts are now in the position shown in Fig. 4, the arm E being' substantially tangential with the roll. The roll is now rotated by means of a motor in the casing B<SP>3</SP>, Fig. 1, of the roll bung, and when the speed of the roll is slightly less than that of the running web, an electromagnet is excited automatically or by means of a push button switch, to move a cam or roller into the path of the fingers E<SP>9</SP>, C<SP>5</SP>. The automatic timing of the action of this magnet may be effected by the electric synchronizing arrangements described in Specifications 294,970 and 294,971, [both in Class 38 (iv)]. The actuation of the finger E<SP>9</SP> causes movement of the arm E about its pivot E' to carry the end of the web, to which adhesive has previously been applied, into contact with the running web and the combined movements of the arm E about its pivot and the frame C about the axis of the roll causes the end of the arm E to move for some distance in the same line as the running web. When the clamp strikes against a guide roller W<SP>2</SP>, Fig. 1, for the web, it is turned about its pivot to cause end portion W' of the web to be torn off and thus release the arm E. At about the same time, the actuation of the finger C<SP>5</SP>withdraws the pawl C<SP>2</SP> from the wheel C' to release the frame C from driving connection with the bung A, and brakes the toggle C<SP>4</SP>to allow a spring D<SP>2</SP>to apply the brakes D to arrest rotation of the frame C. The old web is severed by a blade mounted in a cylinder W' and projected against the action of a spring by an electromagnet.