Method of and Means for Sheet Transfer to and Embossing at a Reeling Station

This invention relates to a new and improved method of and means for sheet transfer and embossing, and is more particularly concerned with the handling and treatment of creped paper sheet web between creping on a Yankee dryer and reeling of the web.

Heretofore the web of creped paper sheet from a Yankee creping doctor has been transferred to the wind-up reel largely unsupported except possibly for one or more small diameter paper carrying rollers and sometimes a single nip calender. Such handling of the web has been satisfactory on machines where reel speeds have been below about 3500 fpm. However, for increased reel speeds approaching 4500 to 7000 fpm or higher, the lightweight creped tissue sheet web becomes increasingly hard to handle in the necessary length of transfer distance from the Yankee dryer to the reel. Furthermore, some tissue manufacturers in order to supply increasing consumer demand for high bulk, lightweight tissue sheets require dry embossing to create higher bulk, and this has heretofore necessitated additional embossing equipment.

According to prior practice, threading of the web onto the reel spool has presented a problem.

An important object of the present invention is to provide a new and improved method of and means for sheet transfer and embossing which will overcome the disadvantages, drawbacks, inefficiencies, shortcomings and problems inherent in prior practice.

Another object of the invention is to provide a new and improved method of and means for transferring and threading creped sheet web from dryer and creping means to a reel spool.

Another object of the invention is to provide a new and improved method of and means for embossing a creped sheet web as it is being wound into a parent roll.

Still another object of the invention is to provide a new and improved method of and means for automatically threading a creped sheet web onto a reel spool.

Still another object of the invention is to provide a new and improved method of and means for effecting multiple embossments of a creped sheet web continuously advancing between a creper and a reeling station.

According to features of the invention, there is provided a method of and means for sheet transfer and embossing wherein a tissue paper web is continuously advanced from creping means, and received on a supporting run of an endless fabric conveyor belt on which the web is transported toward a reel drum over which the belt runs. The continuously advancing web is then threaded onto and continuously wound into a parent roll on a reel spool adjacent to the reel drum. The winding parent roll is pressed against the reel drum and the fabric conveyor belt running over the reel drum, thereby embossing the web in the drum/roll nip.

According to other features of the invention, a method of and apparatus are provided for transporting a creped tissue paper web and automatically threading it onto reeling means.

According to additional features of the invention, a method of and means are provided for dry embossing a creped tissue web at a reeling station, and also optionally upstream from the reeling station.

Other objects, features and advantages of the invention will be readily apparent from the following description of representative embodiments thereof, taken in conjunction with the accompanying drawing although variations and modifications may be effected without departing from the spirit and scope of the novel concepts embodied in the disclosure, and in which:

FIG. 1 is a schematic elevational view of the creping, transfer and reeling section of a creped tissue paper making machine; and

FIG. 2 is a similar schematic elevational view showing a modification.

On reference to the drawings, a papermaking machine frame 5 supports means for drying and creping a tissue paper sheet web W, such means desirably comprising a rotatably driven Yankee dryer roll 7 which, as is usual, is a relatively large metal roll that is provided with a smooth (mirror), finish for receiving and dewatering the web W thereon and is also generally provided with means for heating the interior thereof (indicated diagrammatically at H) in order to accelerate the dewatering of the web moving on the travelling Yankee dryer surface. The largely dewatered web W is directed onto the lower portion of the Yankee dryer 7 by means of a pasting roll 8 which may, if desired, be a suction roll. From the pasting nip between the Yankee dryer 7 and the roll 8, the web travels on the preferably heated surface of the Yankee dryer 7 to a creping device 9 which comprises one or a plurality of creping doctors 10 from which the web W leaves the Yankee dryer 7 and heads toward a reeling station 11.

After passing the creping station 9, the leading end of the web W is separated and deflected from the Yankee roll 7 by means of the creping doctor 10 and received on a supporting run 13 of an endless fabric conveyor and embossing belt 14 which continuously supports and transports the web W to the reeling station 11. The fabric conveyor belt 14 is of full machine width so that it fully supports the entire width of the web W. Optionally the fabric of the endless conveyor belt 14 may or may not be woven in a continuous loop. If it is not a continuous loop, a pin type seam may join the ends. By preference the fabric mesh may be in the range of 10 to 80 mesh, and of at least sufficient porosity to permit air to be blown through the belt.

As closely adjacent as practicable to the creping doctor 10, the receiving end of the transporting run 13 of the conveyor belt 14 starts over a lead-in roll 15, to which the return run of the belt 14 travels from a stretch roll 17. This roll 17 may be adjustably mounted as indicated by the arrow 18 for tensioning the belt, in addition to or independently of a roll 19 for guiding the belt and which may also be adjustable as indicated by the directional arrow 20. At the reeling station 11, the fabric conveyor belt 14 is trained to run over a reel roll or drum 21 which is desirably suitably driven by power means, not shown, to drive the conveyor belt 14.

As the leading end of the web W leaves the Yankee dryer roll 7, it is guided across the narrow gap between the roll 7 and the receiving end of the transporting run 13 of the conveyor belt 14 by means of an air threading shower projected from an orificed manifold 22 located adjacently below the gap. This prevents the leading end of the web from dipping down through the gap, and assures its being propelled onto the continuously travelling conveyor belt 14 as it runs up over the lead-in roll 15 into the transporting run 13. It will be understood that the speed of travel of the conveyor belt 14 will be coordinated with the peripheral speed of rotation of the Yankee dryer drum 7 so that the web W will be efficiently transported to the reeling station 11. Such transporting efficiency is enhanced by inclination of the transporting run 13 generally downwardly from the lead-in roll 15 to the reeling drum 21.

When the advancing end of the web W as transported on the carrying run 13 of the conveyor belt 14 reaches the reeling station 11, it travels under a reeling core or spool 23 which presses down into the conveyor belt sufficiently to maintain good traction. The web W then normally travels on with the conveyor belt and partially around the reel drum 21. As the leading end of the web reaches the reel drum 21, downward curving of the web around the reel drum is assisted by means of an air shower delivered from a manifold 24 located in spaced relation generally above the right side of the reel drum 21 as viewed in FIG. 1. Automatic threading of the web onto the reel spool 23 is initiated after the leading end of the web has travelled with the belt a short distance such as about 90.degree. around the reel drum 21, by upward billowing of that portion of the web advancing past the reel spool 23 by means of an air shower directed from a device such as a manifold 25 located below the fabric conveyor belt and forcing the air upwardly through the conveyor belt in the area between the reel spool 23 in the threading position and the reel drum 21. Thereby the advancing end portion of the web is lifted as shown at a. Since the area of the conveyor belt through which the lifting or billowing air shower is directed is spaced upstream from the area where the air shower from the manifold 24 pushes the web toward the reel drum 21, the advancing extremity of the web is frictionally restrained against upward movement under the influence of the lifting air shower from the manifold 25 so that the web continues to billow upwardly to a position generally indicated at b higher than the shower manifold 24. To assure that the leading end of the web W does not continue to adhere to the conveyor belt and defeat the automatic air threading of the web onto the reel spool 23, a web dislodging safety air shower is directed by means such as an air shower manifold 27, generally upwardly from below the reel drum 21 toward the leading end of the web to dislodge it from the belt and loosen the advancing end portion of the web to facilitate the billowing action of the air shower from the manifold 25. As a safety precaution against possible adherence of the leading end of the web to the conveyor belt with such tenancity as to escape the air shower from the manifold 27, a positive dislodging air shower is projected by means of a shower manifold 28 located above the return run of the conveyor belt immediately after it leaves the reel drum 21, such air shower projecting through the fabric of the belt and blowing the advancing end of the web downwardly and away from the belt and generally toward the air shower device 27.

Upon attaining the air shower thrust billow b, the air shower directed from the shower device 24 thrusting laterally generally toward the reel spool 23, deflects the buckled web toward position c where it overlies the reel spool 23. Under the continuing force of the air showers from the devices 24 and 25, the web continues to buckle and deflect to generally position d and the envelope that has thus developed extends over and beyond the reel spool to the point where it folds down and collapses onto the on running side of the reel spool as indicated at position e and is drawn into the nip of the reel spool and the belt run 13, whereupon the web end portion winds onto the reel spool. Upon completion of the automatic air threading as thus effected, the reel spool is moved by suitable cam or other means (not shown) into the dash line position over the top of and into contact with the reel drum 21 through the web being wound on the reel spool and the conveyor belt and then is continuously held in engagement with the reel drum as the reel spool is lowered to secondary rails 29. Then as winding of the web continues onto the reel spool and a parent roll 30 develops, continuous thrust of the parent roll toward and against the fabric belt running over the reel drum 21 effects continuous dry embossing of the web throughout the parent roll winding. Winding of the parent roll 30 and continuous dry embossing of the web continues until the roll approaches full weight diameter. In the meantime another one of the reel spools 23 is placed in the initial or threading position on the supporting run 13 of the conveyor belt adjacently upstream from the reel drum 21. Upon the parent roll 30 reaching the desired size, it is shifted on the rails 29 away from the reel drum 21 substantially as shown in FIG. 2, the automatic air threading system which during the parent roll winding may have been shut-off is reactivated. Thereby a new air threading cycle is initiated before or after severing the leading end portion of the web. The same automatic air threading sequence as already described is then followed. The full parent roll is moved to the discharge end of the rails 29 as shown in FIG. 1, making room for the next succeeding parent roll to be wound as a continuous process.

If preferred, the automatic air reel spool threading may be assisted by a curved, pivoted sheet tucker 31 (FIG. 2) which generally overlies the threading position of the reel spool 23 and the reel drum 21 in the reeling station 11. In a preferred form, as shown, the sheet tucker 31 is of generally ogee shape having a generally downwardly bowed lead-in section 32 adjacent to the air shower device 24 and acting to hold the billowing web in the position b depressed adjacent to the shower device 24 to facilitate action of the shower device in driving the billowing tuck of the web more rapidly into the succeeding positions c, d and e assisted by a downwardly concave web directing portion 33 of the tucker. The guidance provided by the tucker 31 eliminates any possibility of the air motivated threading leading portion of the web from escaping or deflecting away from the reel spool during the threading operation. Upward deflection of the tucker about a pivot 31a permits shifting movements of the reel spool 23.

It will be understood, of course, that all of the air shower devices 22, 24, 25, 27 and 28 may be supplied from individual or common compressed air source, that each of the devices may have the air pressure thereat and therefrom regulated to suit the particular location and function of the particular air shower device. Further, any suitable sequential operation control may be employed using known electromechanical and pneumatic control devices for the purpose. No specific means for severing the web from the parent roll on completion of winding of the parent roll has been shown because such means are well known in the art.

If additional dry embossing of the creped tissue sheet to obtain higher bulk is desired, an embossing press 34 may be mounted to act on the web W while it is transported along the supporting run 13 of the conveyor belt at an intermediate position between the creping doctor 10 and reeling station 11. Such an additional embossing press may comprise a hard cover roll 35 running in engagement with the underside of the belt run 13 while a soft rubber-like upper roll 37 presses the belt and the tissue web carried thereby against the roll 35.

If for any reason it is deemed desirable, a second fabric endless belt 38 may be guided to run on top of the sheet web W carried by the supporting run 13 of the conveyor belt 14. Suitable rolls 39, 40 and 41 may be installed for guiding the opposite ends of the belt 38 adjacent to but spaced from respectively the reeling station 11 and the creping doctor 10. Where the auxiliary belt 38 is employed, it will be understood that the embossing press 34 may or may not be employed, as preferred. If the embossing press 34 is employed, the embossing action of the upper embossing roll 37 will be through the belt 38 toward the web intervening between the conveyor belt run 13 and the belt 38 and the nip of the rolls 35 and 37.

From the foreging it will be apparent that the present invention provides for high speed operation wherein the web W may be produced at speeds of up to 7000 fpm. Not only is drying and creping of the tissue sheet provided for, but high speed operation is facilitated and enhanced by substantially full support of the creped web from the creper to the reeling station, automatic air threading is provided for, and dry embossing is achieved to the extent desired in a simple and efficient manner.

It will be understood that variations and modifications may be effected without departing from the spirit and scope of the novel concepts of this invention.