GB2085404A - Packaged coils - Google Patents

Abstract

A wound coil in which the material is unwound from the inside through a radial opening 16 in the side of the winding is packaged by shrinking a thin covering over the outside of the wound coil such that the covering is forced into the interstices of the outer coil windings 10, thereby supporting the windows during transportation and during the latter stages of unwinding. The coil is mounted on a perforated, precoated base member 12, provided with a cover disc 14 having a diameter slightly larger than the inner diameter of the wound coil, and the pay out tube 16 is inserted before the mounted coil is conveyed over vacuum platen 18. Heater bank 20 softens film 22 which is caused to descend over the mounted coil by lowering film frame 24, the vacuum drawing the film into the interstices and the film being simultaneously heat sealed to the base member 22. <IMAGE>

Description

SPECIFICATION Packaged coils This invention relates to the packaging of wound coils, and more particularly to the adaptation of skin-packaging to wound coils in which the material is unwound from the inside e.g. through a radial opening in the side of the winding.

Heretofore, windings which have been wound in a figure-8 configuration with at least one radial hole in the side of the winding through which the inner end of the winding can be withdrawn have been packaged in corrugated boxes, with or without the use of supporting cones to aid in supporting the wound coil during transportation and to prevent bird-nesting as the coil is unwound. Such corrugated cardboard stock containers or boxes may also include apertures for inserting payout tubes through the radial opening in the side of the winding to facilitate withdrawal or unwinding of the wound coil. Normally, such packaging of wound coils is done by hand and is time consuming.

The invention provides a method for packaging a wound coil such that the coil may be unwound from the inside, which method comprises positioning the coil on a base member, encapsulating the coil in a film which conforms closely to the surface of the coil, thereby penetrating into interstices between adjacent windings on the said surfaces and providing a passageway from the interior of the coil to the exterior of the package for unwinding of the coil.

The invention includes a package comprising a coil, wound so as to be unwindable from the inside out, mounted on a base member and encapsulated by a film which conforms closely to the surface of the coil, thereby penetrating into interstices between adjacent coil windings, a passageway being provided from the interior of the coil to the exterior of the package for unwinding the coil.

In a preferred practice of the invention the method adopted comprises positioning an end of the wound coil on a base member; positioning a cover disc, having a diameter slightly larger than the inner diameter of the wound coil, on the wound coil opposite the base member; inserting a payout tube in the radial opening of the wound coil; and forming a thin film over the wound coil, base member and cover disc, such that the film is formed in the interstices of the outer windings of the wound coil.

Preferably, the film is drawn into conformity with the coil surface by vaccum applied to the coil interior through perforations in the base member.

The film may be heat sealed to the base member. For this purpose the base member may be pre-coated with a material to enable it to be heat-sealed to the particular film used.

In accordance with well-known techniques of skin packaging, a vacuum may be used to draw the film in tight conformity to the wound coil simultaneously with the application of heat to encapsulate the coil and the base. The film may be a transparent plastics film. During the packaging, the film is caused to enter between the outer coils of the winding, thereby resulting in a support to maintain the coil in position and to support the coils, especially as the material is unwound from the coil and during the last remaining coils of the winding.

The invention can be used to obviate the necessity of packaging the wound coil in a container and also to eliminate the necessity of using a cone or other stabilizing materials to support the coil as it is transported and unwound during its use.

This results from the fact that the thin transparent film enters the interstices of the outer coil winding and encapsulates the winding form. Individual coils are thereby held in position during transportation and payout which provides an extremely stable package.

The resiliency of the film will generally allow additional compression to take place during handling without individual turns of the coil slipping out of place and will generally also act to completely contain the package walls.

When a cover disc is used sized so that its diameter is just slightly larger than the inside diameter of the winding, the film enters the interstices of the edges of the coil, thereby further increasing the stability of the package.

The cover disc and the base member may comprise a corrugated sheet element, for instance sandwiched between a pair of flat sheet elements. The inclusion of a corrugated element will tend to provide strength to assist in supporting the coil for transportation and for use.

The method of packaging the wound coil may be further modified by applying a coating to the base and/or cover disc to provide an adhesive surface for the film to cling to also further aid in encapsulating the coil windings.

The effect of the skin holding the outer layers of the coil is transmitted inwardly layer by layer, each layer holding the one beneath it in place for shipping and payout. This provides the same or similar payout function as cones in the prior art corrugated carton packaging techniques.

As a result of the packaging method of the invention, the costs of packaging a winding are lower than that of a corrugated container packaging. Furthermore, the skin-packaging techniques enable most of the packaging to be done by automatic machinery thereby increasing the productivity such that the winding may be packaged immediately subsequent to its being wound.

The invention will be illustrated by the following description of a preferred embodiment with reference to the accompanying drawings: Figure la shows a wound coil that has been skin-packaged in accordance with the teachings of the invention; Figure lb shows a cross section of the outermost two layers of a wound coil and the manner in which the shrink-wrap engages them; and Figure 2a-2d illustrate the manner in which the wound coil is skin-packaged in accordance with well-known skin-packaging techniques.

Fig. la shows a wound coil that has been skin-packaged in accordance with the method of the invention. The coil 10 rests on the precoated, pre-perforated, corrugated base stock member 1 2. On the upper end windings of coil 10 is cover disc 14 which is also precoated, pre-perforated, corrugated stock material. Prior to covering the winding with a transparent skin, a payout tube 16 is inserted into the radial opening in the side of winding 10.As is readily apparent from Fig. 1 b, the skin 18 is sucked between the interstices of the outer windings of coil winding 10' and 1 0" and firmly and securely attaches the winding to the base member 12 (Fig. Ia) such that it is sandwiched between the base member and the corrugated disc 1 4.

In preparation for the skin-packaging of the winding, the wound coil is placed on top of pre-coated, pre-perforated, corrugated base element 1 2. Payout tube 1 6 is inserted into the radial opening of the winding 10. Pre-coated, pre-perforated, corrugated disc element 14 is then placed on the top portion of winding 1 0.

Disc element 14 has a diameter that is slightly larger than the inner diameter of winding 10 such that its outer peripheral edges rest on top of the windings of wound coil 1 0.

With reference to Figs. 2a-2d, the assembled winding package is placed in the first station of a skin-packaging apparatus and may be automatically conveyed to the vacuum platen 1 8. Heater bank 20 is then energized to soften film 22 to a pliable, thermally-formable state. This is illustrated in Fig. 2a. Film frame 24 is caused to descend onto the assembled winding package as illustrated in Fig. 2b, thereby stretching the film 22 over the winding assembly 24. The vacuum system of the skin-packaging apparatus is then operated to exhaust air below the film and through outlet 26. As illustrated in Fig. 2c, the vacuum draws the film in tight conformity to the wound package assembly ancapsulating it in a tough, truasparent plastic skin. The film 22 is simultaneously heat sealed to the surface of basa member 12.

As is illustrated in Fig. 2d, the film frame is opened and the skin-packaged winding is discharged trom the skin-packaging apparatus automatically re-threading the film for the next skin-packaging operation. The frame is then closed, the film is cut and the frame is elevated to its raised position, thereby permitting entry of a pre-loaded sheet for the next packaging cycle.

Claims (9)

1. A method for packaging a wound coil such that the coil may be unwound from the inside, which method comprises positioning the coil on a base member, encapsulating the coil in a film which conforms closely to the surface of the coil, thereby penetrating into interstices between adjacent windings on the said surfaces, and providing a passageway from the interior of the coil to the exterior of the package for unwinding of the coil.

2. A method of packaging a wound coil wound in a figure-8 configuration with a radial opening in the side thereof extending into the axial opening of the coil such that the coil may be unwound from the inside through the radial opening, which method comprises; positioning an end of the wound coil on a base member; positioning a cover disc, having a diameter slightly larger than the inner diameter of the wound coil, on the wound coil opposite the base member; inserting a payout tube in the radial opening of the wound coil; and forming a thin film over the wound coil, base member and cover disc, such that the film is formed in the interstices of the outer windings of the wound coil.

3. A method as claimed in claim 1 or claim 2 wherein the film is drawn into conformity with the coil surface by vacuum applied to the coil interior through perforations in the base member.

4. A method as claimed in any preceding claim wherein the film is heat sealed to the base member.

5. A method as claimed in any preceding claim wherein the base member contains a corrugated sheet element.

6. A method of packaging a wound coil substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.

7. A packaged wound coil produced by a method as claimed in any preceding claim.

8. A package comprising a coil, wound so as to be unwindable from the inside out, mounted on a base member and encapsulated by a film which conforms closely to the surface of the coil, thereby penetrating into interstices between adjacent coil windings, a passageway being provided from the interior of the coil to the exterior of the package for unwinding the coil.

9. A package of one or more wound coils wound in a figure-8 configuration with a radial opening extending into the central axial opening of the coils such that the coils may be unwound through the radial opening, comprising: a base member for supporting the wound coils; a cover disc having a diameter slightly larger than the inner diameter of the windings and positioned on the edge of the wound coil opposite said base member; and a shrink-wrap tightly enclosing said cover disc, the coil windings and said base member such that the shrink-wrap is embedded in the interstices of the outer windings of said wound coil.

1 0. A package substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.