摘要:
A method for controlling the on-the-fly splicing of a web wound on a first roll to a web wound on a second roll, wherein the first roll is being unwound and the second roll is set in rotation. The method comprises the steps of: transferring a roll carrier supporting the first and second roll from the unwind position to the pasting position, when the first roll reaches one of a first diameter and first circumference value; accelerating the second roll until its peripheral velocity is equal to the velocity of the unwinding web on the first roll, when the first roll reaches one of a second diameter and second circumference value; and operating a pasting and cutting means for pasting the web of the second roll beginning at the pasting tip of the web of the second roll, to the web running off the first roll and for cutting the web running off the first roll at the end of the pasting tab formed by the pasted section of the first and second rolls when the first roll reaches one of a third diameter and third circumference value. In accordance with the invention, the method further comprises the step of continuously calculating the aforesaid diameter or circumference values from a predetermined value for the end diameter of the first roll, a predetermined value for the length of the pasting tab, from one of predetermined and measured time constants of the mechanical members carrying out the method, and from the actual values for the velocity of the web of the first roll and for the rotation of the first roll.
摘要:
Device for splicing one reeled length of web material onto another reeled length during operation of apparatus such as a rotogravure press which continuously consumes the web includes a magnetised element mounted for movement, typically rotation, with said one reel as the latter is run up to a peripheral speed corresponding to the speed of a flight of web from the other reel, and two proximity switches actuated by said element in timed sequence to cause a pasting roller or other element to urge said flight against a predetermined zone of the one reel for adhesion thereto, and a severing knife to cut trailing part of said flight thereafter so that web is then drawn from said one reel without interruption. The reels are conveniently carried in a rotatable cradle enabling their position to be interchanged.
摘要:
A control target for use in indicating annular positioning of the advance end of a web carried by a supply roll including a mounting disc permanently fixed for rotaiton with shaft means employed to removably mount the supply roll and a positioning arm mounted intermediate its ends on the disc for manually induced rotation relative thereto about the axis of the shaft means. The positioning arm carries light reflector and latching or holding devices adjacent its opposite ends; the latching device cooperating with a plurality of annularly spaced holes formed in a face of the disc to adjustably position the reflector device in radial alignment with the advance end of the web.
摘要:
A device for the unwinding and winding of webs of material in spools at one or more winding and unwinding stations carried by the end of one or more fore-arms articulated on a pivotable arm or circular plate, characterised in that it comprises in combination at least one drive means disposed or driven in the pivot axis of the arm or plate, this being a roller driven so as to possess a peripheral speed approaching the linear speed of the web in the machine supplied by the spool being unwound or wound, the latter being pressed at the desired moment upon the drive means which thus imparts its peripheral speed to it, for the purpose of braking in the case of unwinding or drive in the case of winding, and at least one bearing, preferably retractable, disposed at the end of each fore-arm to take up the spool by its hollow centre, with or without shaft, for on the one hand its raising and unwinding and on the other hand its winding and discharge.
摘要:
Unwinder for rolls of paper having individual tape drives engaging the peripheries of the rolls for unwinding the rolls at a uniform linear velocity. The rolls are carried at opposite ends of a turret mounted for adjustable movement about a horizontal axis and moved into its selected position of adjustment by power. The turret support sets of diametrically opposed core shaft chucks for core shafts carrying the rolls of paper. As one roll of paper is being unwound the turret is moved into position to pick up a new roll. The new roll is then positioned in the position formerly occupied by the expiring roll. As the expiring roll is unwound to within a few inches, a knife on a splice arm is activated to shear the end of the expiring roll. A roll on the splice arm is then moved to engage the end of the expiring roll with the new roll and splice the end of the expiring roll to the new roll and carry the new roll to the sheet run.