June 2, 1970 w. K. voss 3,515,183
WINDERS FOR 'PAPER MACHINES Filed Aug. 14, 1968 INVENTOR. WILLIAM K. VOSS Attorney United States Patent 3,515,183 WINDERS FOR PAPER MACHINES William Kenneth Voss, St. Catherines, Ontario, Canada, assignor to Purex Corporation, Ltd., Lakewood, Calif., a corporation of California Filed Aug. 14, 1968, Ser. No. 761,883 Int. Cl. B65h 17/08 US. Cl. 242-66 5 Claims ABSTRACT OF THE DISCLOSURE Apparatus and method for controlling the nip pressure between the roll and the winder drums of a paper machine winder, consisting in introducing a variable controlled air pressure at the nips formed by the paper roll and the drums, the pressure being applied through perforations in the winder drums.
This invention relates to thewinding of paper in rolls and particularly to the winding of such rolls of large diameter. It provides a means and method of regulating and controlling forces to which the roll is subjected while it is being built, in the zones between the roll and the two winder drums. My invention enables the roll to be built with more uniform hardness and, especially in the case of large diameter rolls, so as to minimize or eliminate damage to the paper in the bearing zones in which the paper contacts the winder drums.
As the roll is built, its weight, for any given grade of paper, progressively increases, approximately and neglecting the effect of the core, proportionately to the square of the diameter. It will be obvious that the forces in the bearing zones referred to above increase more and more rapidly as the roll diameter increases. In fact, when a roll diameter exceeds approximately 4045 inches, these forces become critical, effecting paper damage and nonuniformity of roll winding.
A device for relieving pressure in the bearing zones (commonly called nip-relieving) may be used by lifting the ends of the core shaft. It is to be understood that each paper rolls begins by winding consecutive plies on a hollow core or cores maintained in position in the valley between the winder drums at the start of the winding operation, the core or cores being mounted on a common core shaft. The core shaft protrudes beyond the end of the cores and nip-relieving means can be applied to bear a portion of the weight of the roll, provided the core diameter can accommodate a core shaft of sufiicient diameter to avoid undue deflection across the width of the winder. It will be recognized that the core shaft diameter is limited by practical considerations. For example, a winder designed for winding a web of paper 360 inches in width would require a 30 inch diameter core shaft to be capable of nip relieving without unacceptable deflection. Obviously, a core having such a diameter is not practical.
Thus, the problem facing the art has been that of providing means and methods for winding rolls of paper of a diameter in excess of about 40-45 inches without undue damage to the paper in the outer plies of such rolls.
Eiforts have been made to solve this problem, for example, by the provision of duplex winders, but these have the disadvantage of an unacceptably long time cycle when used in association with high-speed paper machines.
My invention has for its objects the control of nip pressure normally encountered in winding rolls of paper by providing air pads between the winding roll and one or both of the winder drums, that is, in the bearing zones referred to above. The method of providing air pads is to introduce a controlled flow of compressed air between 3,515,183 Patented June 2, 1970 ice the nips formed by the paper roll and the drums. My method of providing such an air how is to perforate the drum shells and provide within each shell a sealed pressure box with an arc movement programmed to maintain the position of the boxes at the bearing zones between paper and drums. Each pressure box is connected to a source of compressed air with pressure controlled to increase as the weight of the paper roll increases.
Referring to the drawing,
The figure is a sectional view through a paper roll and supporting winder drums, illustrating my invention.
Referring to the drawing, in which similar reference characters designate corresponding parts throughout; 1 indicates the web of paper coming from the parent reel (not shown) and passing over the tension controlling roll 2, from which the sheet 1 passes through the spaces between winder drums 3 and 4 and enters the bearing zone between winder drums 3 and core 5 shown in its initial position at 5a and is wound on the core 5, the winding of which is accomplished by the rotation in the directions indicated to the driven winder drums 3 and 4.
As the winding proceeds, the size of the paper roll increases, the core rising gradually and vertically from its initial position 5a to subsequent position designated 5b and 50, thus causing the paper roll to increase from its initial size 6a to the larger sizes 6b and 60. As the paper roll increases in size, the bearing zones of contact between the paper roll and the winder drums 3 and 4 will progressively move from the initial position of zones designated 7a and 7b to new zones such as designated 8a and 8b, and later 9a and 9b respectively.
In order to overcome the difficulties and disadvantages hereinbefore mentioned, I now provide that the shells of the winder drums 3 and 4 be perforated for the purpose hereafter to be mentioned, such perforations being shown, for example, by the numeral 10. I then control and reduce nip pressures in the bearing zones between the paper roll and the winder drums by providing variable and controlled air pressure operating through the perforations 10. The air pressure reduces the effect of the roll weight within the bearing zones, and, by varying and controlling the air pressure, damage to the paper, as noted above, is avoided.
In carrying out my invention, I place within each winder drum a non-revolving, but adjustable, pressure box, designated 11b and 11c respectively. To these pressure boxes compressed air is supplied by any known means (not shown). The position of the pressure boxes 11b and may require to be varied with respect to the paper roll so as always to be eifective in the bearing zones, which positioning may be done by means wellknown to those skilled in the art.
It will be apparent that the air pressure requisite to maintain a minimum nip pressure in the bearing zones will be required to be increased as the diameter and weight of the paper roll increases. It will also be apparent that both the positioning of the pressure boxes shown at 11b and 11c and the air pressure required to be maintained therein can be programmed from the position of the core 5 as it ascends vertically from its initial position 5a.
It will also be recognized that, when the core is in its initial position at Sr: no air pressure will be required, but that as the core ascends vertically toward a position where damage is likely to occur to the paper, as, for example, when it approaches the bearing zones 8a and 8b the air pressure will be required to be introduced and therefore increased in a predetermined manner. Programming of this type is well-known to those skilled in the art.
Although a specific embodiment of the invention has been described, it will be understood that various modifications may be made thereto without departing from the 3 spirit thereof, the scope of which is set forth in the appended claims.
The embodiments of the invention in which an exclusive property and privilege is claimed are defined as follows:
1. Means for regulating and controlling the forces to which a paper roll is subjected, during the winding operation, in the zones between the roll and the winder drums, driving 'said roll comprising driven winder drums having perforated shells, and pressure boxes within the winder drums connected with a source of compressed air.
2. Means for regulating and controlling the forces to which a paper roll is subjected, during the winding operation, in the zones between the roll and the winder drums driving said roll, comprising driven winder drums having perforated shells, and pressure boxes within the winder drums connected with a source of compressed air, the pressure boxes being so located that compressed air bears upon the said zones through the perforations in the said shells.
3. Means for regulating and controlling the forces to which a paper roll is subjected, during the winding operation, in the zones between the roll and the winder drums, as claimed in claim 1, and means for varying and regulating the positions of and the pressure within the said 4 pressure boxes as the diameter of the paper roll increases.
4. Means for regulating and controlling the forces to which a paper roll is subjected, during the winding operation, in the zones between the roll and the winder drums, as claimed in claim 2, and means for actuating the air pressure prior to the time at which the diameter of the roll becomes sufficient to cause damage to the outer plies of the paper in the zones between the roll and the winder drums.
5. Method of regulating and controlling the forces to which a paper roll is subjected during the winding operation, in the zones between the roll and the winder drums driving said roll and having perforated shells, comprising applying air pressure through the perforated shells of the winder drums to the underside of said zones.
References Cited UNITED STATES PATENTS 3,346,209 10/1967 Cronin 242-66 FOREIGN PATENTS 1,047,001 12/1958 Germany.
NATHAN L. MINTZ, Primary Examiner UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION 3 ,515 ,183 June 2 1970 Patent No. Dated Inventor s Kenneth VOSS It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
In the heading to the printed specification, lines 4 and S "assignor to Purex Corporation Ltd. Lakewood, Calif. a corporation of California" should read assignor to The Ontario Paper Company Limited, Thorold, Ontario Canada Signed and sealed this 24th day of November 1970 (SEAL) Attest:
WILLIAM E. SCHUYLER, JR.
EDWARD M. FLETCHER,JR.
Commissioner of Patents Attesting Officer USCOMM-DC 60376-5 09 FORM PO-1050 [10-69] v u s covzluuzm' FI'NI'ING ornc: nu o-sn-ssn