Winding – tensioning – or guiding – Convolute winding of material – Simultaneous winding
Reexamination Certificate
1999-07-13
2001-03-20
Jillions, John M. (Department: 3653)
Winding, tensioning, or guiding
Convolute winding of material
Simultaneous winding
C242S571100
Reexamination Certificate
active
06202955
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a method and apparatus for rewinding and is specifically concerned with differential rewinding.
The concept of differential rewinding has been in use for many years and is adopted to accommodate variations in tension or calliper across the web when rewinding material cut from a single roll onto a number of rewind coils.
Traditional methods of differential rewinding rely on the rewind cores slipping around a shaft which is being driven at a greater speed than the moving web of material. One arrangement for effecting differential rewinding is shown in
FIG. 1
of the accompanying drawings.
In
FIG. 1
, a number of rewind cores
10
are mounted, either directly or via adaptors, on a rewind shaft
11
which is driven at a slight overspeed. Steel friction collars
12
keyed to the rewind shaft
11
are mounted on each side of each rewind core
10
or adaptor, and spacer cores
13
are positioned between adjacent rewind cores
10
.
In operation, torque is transmitted to each of the rewind cores
10
, which are free to rotate relative to the rewind shaft
11
, such torque being transmitted frictionally through the steel driving collars
12
which are keyed to the rewind shaft
11
and are loaded axially against the cores
11
and
13
as indicated by the arrows in
FIG. 1
by a pneumatic piston and cylinder mechanism. As the pneumatic pressure is increased, the frictional forces and the transmitted torque increases proportionally. This arrangement is such as to allow differential slip to occur permitting each individual strip to be rewound under optimum conditions to form a rewind roll
14
.
More recent methods of providing differential rewinding have Involved the use of torque-responsive chucks on a keyed shaft and have improved the effectiveness of the differential system. The chucks each have a bronze bush in the centre with a low coefficient of friction and are assembled with mechanically expanded leaves that grip the cores.
The torque-responsive chuck arrangements eliminate the need to remove the spacers and the drive collars from the rewind shaft during reel removal. The chucks retract and release the cores allowing the finished reels to slide over the spacers. The shaft only requires dismantling when the slit pattern is changed to re-positon the chucks.
Although the use of torque-responsive chucks provides an improvement over the arrangement shown In
FIG. 1
, it does have a serious disadvantage in that it involves a reduction in the diameter of the rewind shaft to accommodate the chucks. This results in a dramatic reduction in strength.
The objects of the present invention thus Include the provision of an improved method of differential rewinding and the provision of an improved apparatus for differential rewinding which offer significant advantages over the known systems outlined above.
SUMMARY OF THE INVENTION
According to a first aspect of the present invention there is provided a method of differential rewinding which includes mounting a plurality of cores on a shaft formed with a plurality of apertures containing roller elements urged outwardly into engagement with the cores.
According to a second aspect of the invention there is provided a differential rewinding apparatus comprising a shaft on which, in use, a plurality of cores are mounted, a plurality of apertures in the shaft, roller elements in the apertures and means for urging the roller elements outwardly into engagement with the cores.
Each of the roller elements is preferably arranged to act between a core and a torque-transfer element formed of a material which has a coefficient of sliding friction with the roller elements lower than the coefficient of sliding friction between the roller elements and the cores. The roller elements will accordingly tend to roll relative to the cores.
The cores are preferably formed of cardboard or plastic and the roller elements are preferably ceramic balls, while the torque-transfer elements are preferably in the form of steel cups within which the ceramic balls are seated.
The means for urging the roller elements, i.e. the ceramic balls, into engagement with the cores preferably comprises an inflatable sleeve contained within the rewind shaft and so arranged that, when the pressure within the inflatable sleeve is increased, the torque transferred to the cores is increased.
The apertures in the rewind shaft are preferably arranged in the form of a multi-start helix so that, when cores of different widths are placed side-by-side on the rewind shaft, the number of roller elements which engage a particular core will depend on the width of the core Thus, as the width of a core is increased, the total torque transmitted to that core will be increased. It will thus be possible to rewind cores of different widths at the same time.
Means may be provided for preventing the accumulation of dust between the ceramic balls and the steel cups. Said means preferably comprises means for causing a flow of air out through the apertures in the rewind shaft.
The method and apparatus of the present invention are such that it is not necessary to fit spacers between adjacent cores. Any slit widths can accordingly be accommodated without resetting so that the present invention will enable the machine downtime to be decreased by up to 30% while improving the rewind shaft strength and achieving a dramatic increase in the reel quality.
REFERENCES:
patent: 3815836 (1974-06-01), Munnekehoff et al.
patent: 3817468 (1974-06-01), Smolderen et al.
patent: 4135677 (1979-01-01), Warczak
patent: 4175712 (1979-11-01), Schippers et al.
patent: 4220291 (1980-09-01), Papa
patent: 4496114 (1985-01-01), Kataoka
patent: 4693431 (1987-09-01), Kataoka
patent: 5971314 (1999-10-01), Essert
patent: 296 04 307 U (1979-01-01), None
patent: 195 15 724 (1996-11-01), None
patent: 0 866 017 A1 (1998-09-01), None
patent: WO 95/14630 (1995-06-01), None
Anwendungsspeizifische Spannelemente Fuer LWickelwellen Papier + Kunststoff Verarbeiter vol. 31, No. 1, XP 000584425, dated Jan. 25, 1996.
Jillions John M.
Stoltz Melvin I.
LandOfFree
Method and apparatus for rewinding does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for rewinding, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for rewinding will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2461052