The present invention relates to winders in general, and to apparatus for starting a new winding core in a winder in particular.
When paper, paperboard, or roll pulp is manufactured, it is initially wound into jumbo rolls at the end of a papermaking machine. The jumbo rolls are then processed through a slitter and winder which converts the jumbo roll into smaller rolls i.e., sets from which products are made, from newspapers to, in the case of roll pulp, diapers and sanitary napkins.
Roll pulp and products such as paperboard are relatively thick so that when wound onto a set roll, a roll of a selected diameter is rapidly formed. Once a set roll is formed, a new winding core must be placed in the winder, and a new tail or start formed by cutting the web must be attached to the new winding core. Roll pulp is a thick absorptive web which may be, for example, 1.2 mm thick. Roll pulp is used in such products as diapers and sanitary napkins. In such applications it is the present industry standard that no foreign material such as hot glue residuals find there way into the final product. For this reason, only double-sided sticky tape can be used to attach the web to a cardboard winding core. The tape stays with the cardboard winding core when the roll pulp is used and thus, unlike hot-melt glue, cannot find its way into the finished product.
The normal process of using a winder with roll pulp or board webs, which cannot be moved by an air blow, involves bringing the machine to a stop, slicing the web, placing double-sided sticky tape on a winding core and placing the core in the winder, and manually pressing the roll pulp web onto the double sided tape on the winding core, then winding a set and repeating the process. For thinner paper webs it is possible to automate the process becomes the web can be blown onto the winding core, or picked up by the double-sided sticky tape from the reeling drum. Neither of these processes work if the web is too stiff. With a thicker web it is necessary to start a new reel or set often, and when starting a new set it is necessary to press the thicker web onto the double-sided sticky tape by hand. These steps require significant labor and time, so that the winder may be operating less than half of the time.
What is needed is a way to increase productivity when rewinding thicker paper or fiber webs.
The winder of this invention has a scraper mounted about the axis of a winder drum for circumferential movement. The scraper has a body which has portions forming a semi-cylindrical concave surface which extends in the cross machine direction, the concave surface meets a second cross machine direction extending surface to form a scraping edge. The scraper pivots about the axis of the winder drum, with the scraper edge in engagement with the winder drum surface, and the concave surface facing in the direction of travel defined by the pivotal motion of the scraper about the axis of the winder drum. The concave surface of the scraper has a cylindrical radius such that the concave surface closely matches the surface of a winding core, so that when the scraper is moved about the winder drum axis the scraper edge comes between the winder drum and the web, pushing a web tail onto the concave surface of the scraper. Further motion of the scraper about the winder drum axis brings the scraper concave surface and the web tail into engagement with the winding core and presses the web tail against the winding core. Double-sided sticky tape on the winding core attaches the web to the winding core as the scraper concave surface presses the web tail against the winding core.
An alternative embodiment scraper has a flexible blade mounted in the cross machine direction which functions similar to a spatula, and which scrapes the pulp web off the surface of the winder drum and wipes the pulp web onto the double-sided sticky tape on the winding core.
It is a feature of the present invention to increase the productivity of a slitter winder by reducing the time required to change winding cores when heavier grades of paper, linerboard, and roll pulp are being processed.
It is another feature of the present invention to decrease the need for an operator to perform manual steps when rewinding heavier grades of paper, linerboard and roll pulp.
It is a yet further feature of the present invention to provide a system for positioning and moving a device to transfer and press a relatively heavy and stiff web onto a winding core.
Further objects, features and advantages of the invention will be apparent from the following detailed description when taken in conjunction with the accompanying drawings.
Referring more particularly to
The scraping structure of 42 is comprised of a plurality of cross machine direction sections 44 e.g., one every 10 to 12 inches, of ultrahigh molecular weight (UHMW) plastic such as polyethylene, which are mounted to the scraping structure 42 by elastic pads 46. The sections 44 have portions 45 which engage the elastic pads 46, and portions forming a concave cross machine direction extending semi-cylindrical surface 48. The concave surface 48 meets a second cross machine direction extending surface 49 to form a scraping edge 50.
To start a new winding core 26 in the winder 20, the winder is brought to a stop, and a completed roll set (not shown) is removed from the winder 20. The pulp web 32 is cut to form a tail 62, as shown in
An alternative embodiment scraping and pressing device 56 is shown in
The scraping and pressing device 56 is preferably provided with a cylindrical pushing beam 64 which has an axis 80. As shown in
The cross machine direction beam 58 and the flexible blade 60 mounted thereon, are mounted for rotation to bearings 78. The beam 58 and attached blade 60 rotate together on the bearings about the pushing beam shaft 76.
The cross machine direction beam 58 is thus mounted by the bearings 78 about the axis 80 of the pushing beam 64, so the cross machine direction beam 58 and the flexible blade 60 are rotatable about the axis 80. Rotation about the axis 80 is caused by hydraulic actuators 82, best shown in
Plastic P-shaped structures 90, best shown in
It should be understood that various mechanical arrangements could be used to control the motion of the scraping and pressing device 36 or 56 so as to separate the web tail 62 from the winder drum surface 33 and to press the tail on to a winding core.
It should also be understood that the blade 60 can be constructed of any thin sheet of metal or any other suitable flexible material which can flex so that the wiping action applies an even and controlled pressure to the web tail against the winding core. For example, the blade can be constructed of a 4.75 inch long, in the machine direction, piece of 28 Gage 301 stainless tempered spring steel, of a selected spring constant, such that the blade applies a force to the web on the winding core of about 3 to 4 lbs/linear inch. The blade force on the web and the core can be adjusted by positioning the blade in relation to the winding core. The blade typically wipes approximately a 60 degree sector of the winding core where the tape is present beneath the web. Hot melt glue or other means of binding the web to the core are also possible with the blade wiping action performing the same function by pressing the web to the winding core to form a bond therebetween.
It should be understood that the pressing devices 36 or 56 are particularly useful for transferring a relatively thick web such as board, liner board, and roll pulp onto a winding core. Ordinary paper webs are generally less than 0.010 inches thick whereas board, liner board, and roll pulp are thicker, generally greater than about 0.020 inches thick, and typically 0.040 to 0.060 inches thick for a roll pulp web. It should also be noted that the thick web may not lie on the the surface 57, but, because of the web's inherent stiffness, may be separated from the surface 57 after the nip 30. Thus the scraping action of the scraping and pressing device 36, 56, may constitute no more than the interposing of portions of the scraping and pressing device (i.e. the scraping structure 42, or the blade 60) between the web tail 62 and the drum surface 57.
It is understood that the invention is not limited to the particular construction and arrangement of parts herein illustrated and described, but embraces all such modified forms thereof as come within the scope of the following claims.