US 3433429 A
Description (OCR text may contain errors)
March 18, 1969 E. SCHNITZSPAHN 3,433,429
FILM WINDING APPARATUS Filed April 10, 1967 Sheet I V IllI ATTORNEY i INVENTOR. EMIL SCHNITZPAHN March 18, 1969 E. SCHNITZSPAHN FILM WINDING APPARATUS Sheet Filed April 10, 1967 INVENTOR. EMlL SCHNH ZPAHN ATTO RN EYS 3,433,429 Patented Mar. 18, 1969 3,433,429 FILM WINDING APPARATUS Emil Schnitzspahn, Green Brook, N.J., assignor to Midland-Ross Corporation, Cleveland, Ohio, a corporation of Ghio Filed Apr. 10, 1967, Ser. No. 629,750 US. Cl. 242-65 Int. Cl. B65h 17/08 8 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a winding apparatus for winding an elastic synthetic film under reduced tension, substantially unstressed, about a receiving core.
In the manufacture and subsequent collection of sheet or film tensions are necessarily initially introduced through forming, coating, or printing and by handling. The initial imparted tension if not substantially eliminated will continue to build up in a roll of film as it increases, sometimes increasing to a point causing the crushing of the supporting arbor. It is obviously desirable to reduce the initial high tension to a point where a second package is made.
Two types of winders have been used for elastic film. In one type called centershaft winding, the spool on which the film is wound is rotated by a drive motor exerting a controlled torque to take up the film at a more or less uniform tension. If the film is wound with enough tension to prevent an air film being wound in between layers of film (which would make a soft and nonuniform roll) this tension often stretches the film causing wrinkles to form.
The other type of winding, called surface winding, is accomplished by pressing the spool against a driven metal roll. The film travels from the process equipment to the metal roll and is wound on the spool by the friction forces caused by the tight contact between the spool and the metal roll. Surface winders produce a hard, tight roll of film; however, the film must come to the Winder with enough tension to permit accurate guiding, and this initial tension, coupled with the tight winding operation, causes the problem of excessive residual tension mentioned previously, which can crush the spool or supporting arbor.
Advantageously, the present invention solves the aforesaid difiiculties through the utilization of rubber surfaced nip rolls, the rubber depth being to at least of about one-half inch or such depth so that there occurs displacement upon increasing nip pressure. The rubber nip rolls upon sufficient pressure are in full contact with the passing film advancing with drum and are adapted to be in total control from receipt of the film at an incoming tension until release. During this interval, from initial hold to release, the film will lose sufiicient initial tension enabling the formation of a desirably firm roll or package of film. As mentioned the apparatus is one which includes a large driven drum having a surface of steel, and pressed tightly against two spaced pinch or pressure rubber rolls. The film is initially passed through the nip of a rubberized pressure roll and the drum and on about the drums periphery to a second rubberized pressure roll, or even to a third positioned further about the drums periphery thence to a take-up. The pressure of the rubber rolls on the drum is such so as to slightly deform the contacting rubber surface. The hold and deformation of the pressure rolls surface relieves the tension in the film to an extent so that, upon the release of the film, a relaxation of the tension occurs prior to its winding about an arbor.
The invention will now be described in greater detail in the following specification taken in connection with the accompanying drawings, where:
FIGURE 1 is an isometric view of the plastic film winder including the rubber coated pressure rolls;
FIGURE 2 is a plan view, partly in section, of FIG- URE 1; and
FIGURE 3 is a partial plan view of the steel drum and a pressure roll against it through the nip of which a film is advanced to the take-up.
Theory and empirical verification has shown that a pressure roll covered with a sufiicient depth or thickness of rubber-like material reacts as a larger diameter roll when subjected to pressure in a nip. Should the rubber covered roll be driven by pressure contact with a rotating steel drum it will rotate slightly more slowly as the nip pressure is increased. Thus, an incoming film or web when brought into contact with the driven drum by means of rubber surfaced pressure rolls will lose tension upon leaving the nip prior to being wound onto a package. The extent of relaxing appears to be a function of pressure between the rubber pressure rolls and the feeding steel drum. The surface speed of the steel drum is constant whereas that of the pressure roll changes because of its change in peripheral dimensions. This difference releases the initial tension of the film so that it is wound at such diminished tension producing a softer or less dense roll of film than would otherwise occur.
The apparatus shown in the drawings indicate a source of sheet or film 10 of a width, in this instance, that is to be divided by a slitting operation into about three width equivalent sections 16, 17, 18, subsequently collected into coils 21, 22, 23. The film 10 passes about rolls 11, 12 and about pressure roll 13 bearing against the pulling drum 14 onto and about it until it is taken off about a second pressure roll 19 or 20. The original single film 10 can be cut into the three sections 16, 17, 18 by a spaced slitting knife 15 positioned adjacent the intermediate backing roll 12 which is provided with slits in its periphery for admitting the knife edges. The slit sections 16, 17, 18 are then forwarded about the drum 14 to form rolls 21, 22, 23, the first two being positioned about the first arbor 24 and the third about an opposing arbor 25.
All of the slit film sections are passed about the pressure roll 13, two of the sections 16 and 18 being taken off after traversing about one-fourth the drum 14 periphery and the third slit section 17 after traversing about threefourths of the drum 14 periphery. Upon emerging from the nip of the pressure rolls 13 and 20 the film sections are in reduced tension and are immediately wound onto packages of reduced and acceptable density.
The winder in this example is flexible in that it is continually operated, placing a rotating empty arbor into contact with the drum through the pressure roll in the stead of a filled one without stopping the operation. Such apparatus is sometimes called a turret winder. As FIG- URE 1 shows a balanced turret winder having collecting arbors 24, on one side of the feeding drum 14 and 25, 50 on the other. Each is similarly driven as by a separate motor and a gear box arrangement 32 rotating the arbors 24, 30 by means of a pinion gear 33 mounted at the end of the gear box output shaft and being enmeshed with gear 34 mounted about the spindle shaft 35. The shaft also carries the gear 36 which is adapted to rotate arbors 24, 30 by means of a chain 37 about gears 38, 39. All transmission of power to the various gears 36, 38, 39 is through the common chain drive 37. The driving means herein mentioned are used primarily to keep the rewinding roll rotating as the turret is indexed to remove the full roll from contacting with the winding rolls and to bring the new core into winding contact. In opposition is an identical turret film take-up. The turret means 40, of the first rotating take-up, is actuated by means of an air cylinder 41 in a well known manner being adapted to swing the take-up 180 to permit the removal of a full roll of film and place into take-up position an empty arbor.
The driven steel drum 14 is mounted about shaft 52 which is rotated by an end gear 53 rotated by means of the chain 54 positioned in and moving about the gear 55. The latter gear itself is mounted on the end of the drive shaft 56 of the motor 57. There is a power take-off olf the shaft 52 for driving the metal tension roll 12. A gear 59 is secured to and about the driven supporting shaft 52 and drives by means of a chain 60, the gear 61 mounted on the shaft 62 that supports the tension roll 12. The speed of the tension roll 12 and that of the drum 14 are correlated to provide the same surface advance rate for the passing film 10. The pressure nip rolls 13, 19 and 20 are idler rolls and they are covered with rubber to a depth so that, when they are impressed against the drum 14, a prolonged nip is had. This creates for a firm hold of the slit film until it is released. The prolonged continuous surface contact is desirable so that upon release by the pressure rolls the film tension is substantially and uniformly decreased.
The pressure rolls 13, 19 are covered to an extent from about /2 to 1% inch thick of rubber or rubber-like material adapted to deform temporarily when pressure is applied. Pressure is applied by hydraulic actuated pistons and cylinders 65 and 67 acting on arms 70, 72 which pivot about points 73, 75A. The take-off pressure roll 19 is mounted on a shaft 75 itself secured in the opposing extension 76 of the arm 70. Upon application of hydraulic pressure the cylinders 65 will thrust outwardly pivoting arms 70 forcing the roll 19 into the steel surface of the drum 14 to indent the rubbery surface of roll 19. The pinch or pressure roll 20 in opposition to roll 19 is actuated in a like manner. Hydraulic cylinder 66 is adapted to move arm 71 about pivot 74 forcing the roll 20 to impress its surface over that of the drum. The film section 17 is laid on the roll 23 in a likewise relaxed condition as film sections 21 and 22. Power means (not shown) to actuate the winder are also provided driving it up to initial take-up speeds then being released as the pressure increases so that the idler 20 takes up the drive. Again a similar turret rotating apparatus 80 is provided for rotating the winders into position for take-up of film.
As shown in FIGURE 3 arubber pressure roll, as roll 19, is impressed against the surface of the drum 14 to form a prolonged nip therewith. The peripheral speed of the film on the drum is constant and therefore its tension is constant since the initial rubberized pressure is securely holding it. As the particular volume goes through the nip, the thickness of the rubber covering is decreased. Since the width is constant, the surface speed must increase for the same volume to pass in a given period of time. As the surface speed increases in the nip, this is equivalent to the roll acting as if it were a larger diameter in the nip, as a roll of larger diameter would have a greater surface speed at a given rotational speed. The film is advanced over the greater periphery of the drum and is let off over a decreased periphery of the pressure roll 19 at a point where the diameter is about the least, this induces a reduction of tension. Firm packages have resulted when wound on the aforesaid apparatus with no destruction of cores.
What is claimed is:
1. A film winding apparatus comprising, a film source, a drum for advancing said film, a pressure idler roll having a flexible rubber-like surface in contact with said drum, said film passing through the nip formed by the drum and the said pressure roll and around with said drum, a second pressure idler roll having a flexible rubberlike surface positioned at a distance from said first pressure roll and being in contact with said drum and forming a second nip therewith through which said film passes, and a core for winding the emerging film from said second nip positioned adjacent to and being driven by said second pressure roll.
2. A film winding apparatus comprising, a film source, adrum for advancing said film, a pressure idler roll having a rubber-like surface in contact with and riding on said drum, said film being forwarded through the nip formed by said pressure roll and said drum, a second pressure idler roll having a rubber-like surface positioned at some distance from said first pressure roll and in contact with said drum and forming a second nip through which said film passes, and a core for winding said film positioned adjacent said second pressure roll and driven thereby.
3. The film winding apparatus of claim 2 where the said idler pressure rolls have rubber-like surfaces of at least about one-half inch in thickness.
4. The film winding apparatus of claim 2 where each of the said idler pressure rolls is impressed against the said drum by its own means.
5. A film winding apparatus comprising, a film source, a driven drum for advancing said film, a pressure idler roll having a rubber-like surface in contact with and riding on said drum, means for impressing said idler roll onto said drum, said film being forwarded through the nip formed by said pressure roll and said drum, 3. second pressure idler roll having a rubber-like surface positioned at some distance from said first pressure roll and in contact with said drum and forming a second nip through which said film passes, means for impressing said second idler roll onto said drum, a core for winding said film positioned adjacent said second pressure roll and driven thereby, means for impressing said core against said second idler roll, a spare core for the replacement of said first mentioned core upon full winding, and means for placing said second core in the stead of the first.
6. The film winding apparatus of claim 5 where said second replacement core is rotated prior to its film takeup position, and has power means for effecting its rotation.
7. A film winding apparatus comprising, a film source, a driven drum for advancing said film, a pressure idler roll having a rubber-like surface in contact with and riding on said drum, means for impressing said idler roll onto said drum, said film being forwarded through the nip formed by said pressure roll and said drum, a second pressure idler roll having a rubber-like surface positioned at some distance from said first pressure roll and in contact with said drum and forming a second nip through which said film passes, means for impressing said second idler roll onto said drum, a third idler with a rubber-like surface positioned in contact with said drum opposite said second idler roll, means for impressing said third roll onto said drum, cores for winding said film positioned adjacent said second and third pressure rolls and driven thereby, spare cores in position for replacement of filled cores being wound, and separate means for placing said spare cores into film winding positions into contact with said second and third idler rolls.
8. The film Winding apparatus of claim 7 where the spare cores are positioned on opposite sides of the driven drum and of the cores being wound.
6 References Cited UNITED STATES PATENTS 5/1961 Rockstrom et a1. 24265 11/1964 Billingsley 24256.2 7/1967 Mastriani 24256.2
FOREIGN PATENTS 1/1966 France.
US. Cl. X.R.