Background of the Invention
The present invention relates to a method and to a two-drum winder for the winding of endlessly fed webs, and particularly webs of paper from roll slitting machines, with the formation of individual wound rolls.
The individual wound rolls lie on two carrier drums, arranged parallel to each other, i.e. an arriving first carrier drum and a departing second carrier drum with respect to the wound roll located in the carrier drum bed thereof and the roll is driven by the drums during the winding process. Then the completely wound roll is lifted off and the web is pressed at a first holding point against the wound roll and at a second holding point against one of the two carrier drums. The web is then stretched over a knife between the two holding points and thereby cut off. The finished wound roll is now removed, and the starting end of the new web is driven back in the direction opposite the web feed direction by means of compressed air and it is taken up by a new winding core which has been made ready, and wound up.
This type of web winding is known from Austrian Pat. No. 332,214, which corresponds to U.S. Pat. No. 3,841,578. There the web travels upward from below between the carrier drums and onto the roll to be wound. The web wraps around a part of the second carrier drum as seen in the direction of winding. The new winding core is, however, not placed on top of the carrier drums but is applied from below to the carrier drums and is pre-wound there. Thereupon the two carrier drums are moved apart, the pre-wound winding core is brought upward into the carrier-drum bed and the two carrier drums are again brought to the required narrow distance from each other. Since the carrier drums are several meters long and are normally also driven, this means an expensive construction. Furthermore, glue must be applied to the web so that the end of the new web produced by the cutting process is in each case taken up by the new winding core and is wound. Nevertheless, the starting end of the newly cut web may undesirably not remain attached to the new winding core, but may instead slide away downward past the new winding core.
U.S. Pat. No. 3,918,654 shows a double-drum winder in which the web is not passed upward from below between the carrier drums but is instead conducted over the two drums. The new winding core is in each case applied from above onto the web and is pressed together with the web into the drum bed. In this case also, gluing of the web of paper is necessary so that it be grasped by the new winding core and then wound. After completion of a wound roll, the web is cut by a knife that is pushed through the section of the web in the upward direction between the two drums. The web is moved, between the two drums, around the lower section of the new winding core. Only a small amount of space is available for the knife between the drums and the device for the actuation of the knife is complicated. Furthermore, the knife must also be frequently replaced since it can cut the web on the winding core only when it is extremely sharp. Furthermore, there is also the danger that, despite the gluing, the starting end of the new web will not be wound by the winding core, but will instead move away. In addition to this, with both of the known methods and the double-drum rollers, there is a danger that the carrier drums and the web of paper being dirtied by glue so that the web will remain stuck in undesired fashion in the machine and will be damaged.
Summary of the Invention
The object of the present invention is to effect the replacement of wound rolls in structurally simple manner without interference and in automatic fashion.
The invention permits the carrier drums to remain in their original position without change. The new winding core is in each case brought directly onto the carrier drums in the carrier-drum bed. The starting end of the new web, which is produced by the cutting process is conducted by compressed air around a part of the new winding core and into the feed slot which is formed between the winding core and the following section of web. In this way, it is no longer possible for the starting end of the web to veer away from the new winding core. The entire change of rolls can be effected automatically. Similarly, the introduction of the new winding cores can also take place automatically when an automatic winding-core feed device is arranged in known manner at the end of the double-drum winder.
The invention is particularly well-suited for winding cores which have been pushed in the form of tubes over flexurally rigid winding rods.
The web of paper continuously produced by a paper making machine may, for instance, be 9 m wide. This wide web is cut by a roll slitting machine into several narrow webs. These narrower webs are wound into individual wound rolls in a double-drum winder of the type described here. In this connection, the two drums normally carry, alongside of each other, at the same time, as many winding rolls as the number of webs cut by the roll slitting machine. After the individual wound rolls have reached the desired diameter, they must be removed, insofar as possible, without any loss of time and the individual web must be separated from the wound rolls and be brought to new winding cores which have already been made available.
In accordance with the invention, after the completion of a winding process, the roll slitting machine and the double drum winder are stopped. A pressure roll is swung against the first carrier drum in order to hold the web fast. The completely wound roll is lifted and a cutting head, which is rotatably supported on the second carrier drum, is swung up to the finished wound roll.
With feed speed and with connected blow pipes on the pressing roll and in the drum nip, the web is blown so far between the cutting head and the second drum that a loop of web of a given length is formed. Thereupon, one or more rolls, supported in the cutting head, are swung against the second carrier drum. Next, a slitting knife is pushed from the cutting head into the web which is stretched tightly over the cutting head. Cutting of the web is thereby effected. For removal of the loop, the rolls supported in the cutting head are swung away briefly and a blow pipe which is present at the first carrier drum blows the web over the second carrier drum so that the starting end of the new web produced by the cutting of the web comes to lie over another blow pipe which is arranged, fixed in position, in front of the second carrier drum. Thereupon, the blow pipe arranged at the first drum is disconnected together with the roll slitting machine, and the cutting head with rollers resting against the second carrier drum passes back into the ready position. The newly cut web lies between the second carrier drum and the rollers of the cutting head.
After the removal of the finished wound roll and the insertion of the new winding core or of a winding rod provided with winding tubes into the drum bed, a pressure drum which was holding the web to the first carrier drum is swung away from the first carrier drum and the rolls provided on the cutting head are swung away from the second carrier drum so that the further blow pipe which is now connected blows the web upward in front of the second carrier drum, and blow nozzles present in the cutting head conduct the web over the winding core when the cutting head is briefly swung upward, in order to assist in the placement of the starting end of the new web around the new winding core. Thereupon, the blow pipe arranged in front of the second carrier drum and the blow nozzles present in the cutting head are disconnected and the cutting head is moved back into its ready position. A new winding process can now be started.
Other objects and features of the invention will be apparent from the following description considered with reference to the drawings:
Brief Description of the Drawings
FIG. 1 is a diagrammatic side view of a double drum winder in accordance with the invention,
FIG. 2 is a side view of this double drum winder, shown together with a roll slitting machine and a tube insertion device,
FIG. 3 is an enlarged sectional view of the cutting device, and
FIG. 4 is a diagrammatic top view of the double drum winder of FIG. 1.
Description of the Preferred Embodiments
There is a roll slitting machine 1, only a part of a guide roller of which is visible in FIG. 1. The web 2 which is to be wound passes from the slitting machine 1 over another guide roller 3 onto the top portion of the first carrier drum 4 and from there it passes onto the top portion of the second carrier drum 5. From the drum 5, the web is returned in the direction counter to its feed direction and is then wound on a winding core 6 lying in the drum bed above and between the drums 4 and 5 and on top of the web 2 so that a wound roll 7 is formed on the core. At least one of the two carrier drums 4 and 5 is driven and thereby turns the winding core 6 and the wound roll 7 that is formed on the core.
Normally, several webs 2 travel simultaneously alongside each other on the carrier drums 4, 5 and are wound there onto winding cores 6. In this connection, the winding cores 6 are normally comprised of winding tubes 8 which are placed over a flexurally rigid winding rod 9. The winding rod 9 together with the winding tubes 8 is, in case of automatic operation, automatically taken from a tube insertion device 11 and placed into the drum bed of the carrier drums 4 and 5.
A cutting or separating device 13, is supported by means of swingable supporting levers 14 located on both sides in collar bearings 15 which are arranged on the second carrier drum, whereby the axis of swing of the cutting device, which swinging occurs on the levers 14, coincided with the rotation axis of the second carrier drum.
The cutting device 13 with the supporting levers 14 can be swung around the axis of the drum 5 by cylinders 16, which are rotatably supported by bearing brackets 17 on the floor and by forked heads 18 on the supporting levers 14.
In the cutting device 13, a plurality of pressing rolls 20 are supported in an axial array, one behind the other, in a row parallel to the arrays of carrier drums 4 and 5. Movement of the rolls 20 of the cutting device 13 against and away from the second carrier drum 5 is effected by means of cylinders 21 which are rotatably supported between the supporting levers 14 and the cutting device 13.
Ribs 26 are provided for supporting of the rolls 20 in the cutting device 13.
Holding brackets 29 arranged on both sides on stands 28, receive the cutting device 13 in the ready position.
A knife or cutting blade 22 is suspended from the cutting device 13 in an elastically swingable manner by means of a spring plate 23. The knife 22 can be swung by inflation of an inflatable hose 24 to protrude from the cutting device into the path of the web 2 and can be swung back again to retract into the cutting device by the initial tension of the spring plate 23. Instead of an inflatable hose 24, a hydraulic expansion element could also be employed. Within the basic body of the cutting device 13, there is an air chamber with blow nozzles 25 which serves as a blowing device. The nozzles of this blowing device are directed toward the web, back toward the feed direction of the web and are directed between the wound roll 7 and the pressing rolls 20. These nozzles assist in directing the end of the cut web onto a new core.
Between holding brackets 30 a blow pipe 31 is supported. Its nozzles are directed opposite the direction of rotation of the second carrier drum 5 and it also serves as a blowing device. It is the principal means for directing the cut end of the web onto a new core 6.
A cross member 33 is swingably supported on brackets 32. In the cross member 33, there is rotatably supported a pressure drum 34. By means of cylinders 35 the cross member can be swung, enabling the pressure drum 34 to be placed against the first carrier drum 4. In this way, the web of paper 2 can be held fast between the pressure drum 34 and the first carrier drum 4 and the web can be prevented from sliding out or rearwardly.
Furthermore, a blow pipe 36 is provided on the cross member 33. Its nozzles are so directed that they can blow a stream of air through the space between the two carrier drums 4 and 5, on the one hand, and the wound roll 7 and the cutting device 13, on the other hand. This too serves as a blowing device. The blow pipe 36 blows against the web which is then being held against the wound roll 7 by the cutting device for forming a loop 40 of the web.
There is a blow pipe 38 arranged between the two carrier drums 4 and 5 and below the web 2. It has upwardly directed nozzles which, during the replacement of the cores, give off a stream of air against the bottom of the web 2 and thereby, together with the stream of air from the blow pipe 36, guide the web in the direction of movement of the web, as will be further described below. The blow pipe 38 is yet another blowing device.
The apparatus of the invention operates as follows. After completion of a wound roll 7, the roll slitting machine 1 and the double drum winder are stopped. Then the pressure drum 34 together with the blow pipe 36 are swung against and press upon the first carrier drum 4. The pressure drum 34 holds the web 2 firmly on the first carrier drum 4 so that it cannot slide backward upon the subsequent cutting of the web. The wound roll 7 is then lifted by a known lifting device 39 from the lower position 7' to the upraised position 7" so that a space is produced between the wound roll 7 and the two carrier drums 4 and 5 on which the roll had previously sat. The cutting device 13 is now swung against the wound roll 7. The roll slitting machine and the double drum winder are then again connected and operate with a predetermined speed. The web is thus being fed again. At the same time, the blow pipes 36 and 38 are actuated so that as the web 2 is being fed, it is also being blown between the cutting device 13 and second carrier drum 5, thereby producing a web loop 40.
When a given length of the loop 40 is produced, the rollers 20 of the cutting device 13 are swung against the second carrier drum 5 and the knife 22 is moved into the stretched web 2. The rotating carrier drum 5 pulls the web loop tight against the protruding knife while the cutting device holds the web against the roll 7. Once the web has been cut, the knife 22 thereupon retracts into its starting position. The rolls 20 of the cutting device 13 are again moved away from the second carrier drum 5 and are held spaced from it and the continued blowing by the blow pipe 36 eliminates the loop 40 and the web 2 comes to lie above the carrier drum 5 and above the blow pipe 31. Then the blow pipe 36 is disconnected, together with the roll slitting machine and the double-drum winder.
The cutting device 13 then moves into the ready position, its dot-dash line position. The rolls 20 supported on it are held still against the carrier drum 5 for the time being. In this way, the rolls 20 continue to hold the web 2 fast against the carrier drum 5.
After the wound roll 7 has been lifted to the further upraised position 7''' and has then been removed from the position 7''' by a known changing device 42 and after the changing device 42 has taken a new winding core 6 from the tube insertion device 10 and placed it into a lifting device 39, the pressure drum 34 is lifted from the first carrier drum 4.
Then the rolls 20 are swung away from the second carrier drum 5, and the blow pipe 31 is connected, so that it blows the starting end of the new web, that was produced by the cutting device, upward. Furthermore, the cutting device 13 is swung upward so that its blowing device 25 assists the blow pipe 31, and the web is conducted over the new winding core 6 which the lifting device 39 has in the meantime lowered into the drum bed of the two drums 4 and 5.
The cutting device 13 is shown in solid line in operating position in FIG. 1. Furthermore it is shown in dot-dash line in its ready position. The operating position that exists when the rollers 20 rest against the second carrier drum 5 is indicated by dashed lines.
Upon the disconnecting of the blow pipe 31 and of the blow device 25 of the cutting device 13, the cutting device 13 is again swung into the ready position. The swinging of the cutting device 13 is around the pivot point of the second carrier drum 5.
The double drum winder is now ready to start a new winding process.
Although the present invention has been described in connection with a preferred embodiment thereof, many variations and modifications will now become apparent to those skilled in the art. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein, but only by the appended claims.