GB2405849A

GB2405849A - Applying pre-formed sleeves

Info

Publication number: GB2405849A
Application number: GB0321549A
Authority: GB
Inventors: Peter Woolls
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-09-13
Filing date: 2003-09-13
Publication date: 2005-03-16
Anticipated expiration: 2023-09-13
Also published as: GB0321549D0; GB2405849B

Abstract

A banding apparatus for placing cylindrical bands 10 onto products 12 advanced by a moving conveyor 14 comprises a transport drum 60 for mounting above the conveyor 14 with its axis of rotation transverse to the direction of movement of the conveyor 14. The drum 60 serves to transport bands individually from a loading position at which bands, severed from tubular stock 18, are placed on the drum 60, to a transfer position at which bands are removed from the drum and are each placed on a respective product 12 on the conveyor 14. The bands 10 are transported by the drum 60 with their axes extending tangentially to the axis of the drum and the direction of rotation of the drum is such that the bands 10 arrive at the transfer position from the opposite direction to the products 12. The bands are distended by a former 20 then partially re-flattened and held on the drum by a vacuum. The bands may be shrink wrapping, tamper evident sleeves or labels. Elongate products such as lipsticks or batteries may be conveyed and banded while horizontal, Figure 7.

Description

BANDING APPARATUS

The present invention relates to a banding apparatus for fitting a band or sleeve over a product.

In packaging, it is often desired to fit a sleeve, usually made of a heat shrinkable plastics material, over a product. If the product is a jar, a narrow band may be fitted around the lid to act as a tamper evident seal. With lo other products, a longer sleeve may be fitted over all or most of the axial length of the product to act as a label, or as a heat shrink wrapping. The term "band" will hereinafter be used to include all such sleeves, regardless of their axial length or their function.

It has already been proposed to provide a banding apparatus in which a band is cut from tubular stock and placed directly over a product after its end has been opened. However, it takes time to cut and open a band from the tubular stock, to advance it to a position near the product and then to slip it onto the product. The time taken to complete this entire operation dictates the maximum rate at which products can come off the conveyor.

To permit faster production rates, it has been proposed in US-5,398,395 to place the bands cut from the tubular stock with their ends open on arms that project radially from a transport drum, the bands being held on the radial arms by a vacuum. The bands are held with their axes extending radially with respect to the axis of rotation of the drum and with their radially outward ends opened. With this orientation, each band is dropped on to the top a product as it is advanced on a conveyor passing beneath the drum. As best shown in Figure 10 of US-5,398,395, the drum rotates about an axis transverse to the direction of movement of the surface of the conveyor and its sense of rotation is such that during the transfer of a band from one 2 - of the radial arms of the drum onto a product, the band and the product both move in the same direction.

The advantage of the use a transport drum is that it allows a band to be cut from the tubular stock at the same time as a previously cut band is placed on a product, thus enabling higher production rates to be achieved. However, the banding machine of US-5,398,395 can still not be used to achieve high production rates with bands of increased axial lo length. This is because the tangential distance between the ends of consecutive bands carried by the transport drum increases with the axial length of the bands and this dictates the minimum separation between the products on the conveyor. In order to maintain a given production rate while increasing the separation between the products on the conveyor, it is necessary to increase the speed of movement of the conveyor and this is often not practicable for a variety of reasons.

With a view to mitigating the foregoing disadvantage, the present invention provides a banding apparatus for placing cylindrical bands onto products advanced by a moving conveyor, the apparatus comprising a supply of bands, a transport drum for mounting above the conveyor with its axis of rotation transverse to the direction of movement of the conveyor, which drum serves to transport bands individually from a loading position at which bands from the supply are placed on the drum to a transfer position at which bands transported by the drum are removed from the drum and are each placed on a respective product on the conveyor, characterized in that the bands are transported by the drum with their axes extending tangentially to the axis of the drum and in that the direction of rotation of the drum is such that the bands arrive at the transfer position from the opposite direction to the products. - 3 -

In the invention, because the bands extend tangentially with respect to the axis of the drum, the distance between their ends is not affected by their axial length. Also, because the bands carried by the drum arrive at the transfer position while moving in the opposite direction to conveyor, they do not interfere in any way with the progress of the products carried by the conveyor. Hence the banding machine will operate successfully regardless of the separation of the products along the conveyor, thereby allowing high lo production rates to be achieved without excessive increase in the speed of movement of the conveyor.

The drum is preferably formed with flat sides to support the bands over a substantial part of their axial length.

Conveniently, the bands are held on to the drum by application of a vacuum.

While in the form of a roll of tubular stock, the bands have creases along opposite edges and because the plastics material of the bands is thin, it would be difficult to open the ends of the bands after they have been severed from the tubular stock. This problem may be avoided, as described in US-5,398,395, by using a first pair of free running rollers to support and retain a former situated inside the tubular stock which opens it into a cylinder and by then flattening the cylinder by means of a second pair of rollers that are perpendicular to the first pair. In this way, the tubular stock is fed by the second pair of rollers with its original creases lying one above the other. Bands now severed from the tubular stock will tend naturally to open into a cylinder and if held on the transport drum by vacuum applied on opposite sides of one of the original creases, then they will remain as open cylinders as they are transported by the drum. 4 -

The products, if capable of being transported in a stable manner, are preferably supported on the conveyor with vertical longitudinal axes, so that a band placed over a product at the transfer position will be assisted by the action or gravity or mechanical means when dropping down to envelop the product. In this case, the bands are preferably released from the drum with their longitudinal axes inclined to the vertical. When the axis is inclined at 30 to the vertical, the end of the band defines an elliptical mouth in lo a plane that is inclined at 30 to the horizontal to catch and slip over the top of a product as it is advanced by the conveyor.

It is however an advantage of the invention that it can be used with products that are too unstable to be transported vertically by the conveyor. In this case, the products may be advanced in a horizontal attitude into the transfer position and the bands may be released from the drum while they are substantially horizontal after they have been fitted over the leading ends of products.

The invention will now be described further, by way of example, with reference to the accompanying drawing, in which: Figure 1 is a schematic perspective view of a banding apparatus of the invention arranged above a conveyor, Figure 2 is a schematic representation of the former used to open the tubular stock before it is cut into individual bands, Figure 3 is a schematic cut away view showing the vacuum lines used to hold the cut bands on the transport drum, Figure 4 is a side view of the banding apparatus shown in Figure 1, Figures 5 and 6 are views similar to Figure 4 showing alternative constructions of the drum, and - 5 Figure 7 shows a banding apparatus for products carried horizontally on a conveyor.

Figure 1 shows a banding apparatus for placing bands 10 on products 12 standing upright on a conveyor 14 which moves from left to right in the drawing, as represented by the arrow 16. The bands are cut from tubular stock 18 that is unwound from a roll (not shown) and enters the apparatus as a tube flattened in a vertical plane with creases 22, 24 lo along its upper and lower edges.

The flattened tube 18 passes over a former 20, shown in greater detail in Figure 2, which opens the tube and then flattens it in a horizontal plane with its previous creases 22, 24 lying one above the other. The former 20 comprises two triangular plates 26, 28 which are joined to one another along their bases. The apices of the two triangles 26 and 28 define a line spaced from their common base along the direction of movement of the tube 18 and extending perpendicular to the base. The former 20 fits entirely within the tubular stock 18 and to keep it stationary as the surrounding tubular stock 18 is moved over it, it is provided with a flat rectangular plate 30 joined to the bases of the two triangles 26 and 28 and a rod 32 secured to the opposite side of the plate 30. The plate 30 is positioned between two rollers (not shown) lying outside the tubular stock. The spacing between the rollers is less than the diameter of the rod 32 thereby preventing the former 20 from moving with the stock 18.

The former 20 is introduced into the tubular stock 18 before it is trapped between the rollers that straddle the plate 30. As the stock travels over the triangles 26 and 28 it is at first opened and then partially re-flattened in an orthogonal plane. The creases 22 and 24 in trying to return to their original position tend to open the tubular stock but they area prevented from doing so by drive rollers 40 - 6 - which drive the stock through a cutter 50 and on to a transport drum 60. The leading edge of the stock is held on the drum 60 by vacuum applied to opposite sides of the crease 24. A band of the desired axial length is cut from the stock 18 by operating the cutter 50 and the cut band then springs out into a cylinder of which the longitudinal axis lies tangentially with respect to the axis of the drum 60.

As better shown in Figure 4, the band 10 that is placed horizontally on the drum 60 at the loading position after having been severed from the tubular stock 18 by the cutter is transported to a transfer position after having travailed clockwise, as represented by the arrow 62, through an angle of 120 . When the band 10 reaches the transfer position, its axis lies at 30 to the vertical and its open mouth in a plane at 30 to the horizontal. The mouth of the band thus hangs beneath the drum and it collides with the leading side of the next product 12 on the conveyor 10, which is moving in the opposite direction. Once one side of the band has caught on to the product, the vacuum holding the band on the drum is released by the continued rotation of the drum and the band drops onto the product, assisted by the action of gravity or mechanical means.

It will be clear from the above description that vacuum is only applied to the parts of the surface of the drum that are located approximately between the twelve o'clock and four o'clock positions, as seen in Figure 4. This is achieved in the manner shown schematically in Figure 3. The drum has three air galleries 70 that extend axially through the transport drum 60. Each of the galleries is connected to holes 72 that apply a vacuum on opposite sides of one of the creases of the band to hold the band against the surface of the drum 60 with its end open. A further hole 76 communicating with the gallery 70 opens into an arcuate recess 77 in the bearing shell 78 of the drum 60 to allow - 7 - air to be drawn from the gallery 70 in the desired angular positions of the gallery but not in others.

The embodiment of Figure 5 differs from that of Figure 4 only in that the drum 160 has six flat sides instead of three and rotates through 60 per band placement, this being better suited to short bands.

In the embodiment of Figure 6, the flat sides of the lo drum 260 for receiving the bands 10 are extended so that the drum is generally triangular in cross section. This construction is better suited to longer bands 10 as they are supported by vacuum over a greater proportion of their length. It will be noted that the bands 10 may overhang the sides of the drum 260 and their length is not therefore restricted by the size of the sides of the drum 260.

All the previously described embodiments are intended to place bands on products 12 that are carried upright on a conveyor 14, as shown in Figure 1. By contrast, the embodiment of Figure 7 is intended for products, such as lipsticks or batteries, that will not balance properly on a moving conveyor and must therefore lie horizontally while being transported by the conveyor. The products 712 are moved along two horizontally spaced inclined plates 714 which define a V-shaped support surface with a gap between the plates 714 at the base of the V. Prongs 716 on an endless belt 718 arranged beneath the plates 714 push the individual articles along the V-shaped support surface while maintaining a predetermined separation between them. The drum 760 of the banding apparatus has a drum 760 with four sides, which is indexed by 90 for each band placement, and the bands are transferred from the drum 760 to the products when the bands 10 are horizontal.

In operation, a band 10 is first rotated by the drum 760 to a horizontal position in which it rests on the V 8 - shaped support surface defined by the plates 714. When the next product 712 is pushed by one of the prongs 716 of the endless belt 718 along the V-shaped support surface, it enters into the band 10 which has been placed in its path by the drum 760. Th.e prong 716 eventually picks up the end of the band and it is separated from the drum 760 and transported along with the product 712. As soon as the prong 716 has cleared the drum 760, the drum is rotated through 90 to advance the next band into position to receive the lo next product 712.

In all embodiments, the transport drum is preferably adjustably mounted for movement horizontally towards and away from the cutter 50, as represented by arrows in Figure 5, in order to suit the axial length of the bands. - 9 -

Claims

1. A banding apparatus for placing cylindrical bands onto products advanced by a moving conveyor, the apparatus comprising a supply of bands, a transport drum for mounting above the conveyor with its axis of rotation transverse to the direction of movement of the conveyor, which drum serves to transport bands individually from a loading position at which bands from the supply are placed on the drum to a lo transfer position at which bands transported by the drum are removed from the drum and are each placed on a respective product on the conveyor, characterized in that the bands are transported by the drum with their axes extending tangentially to the axis of the drum and in that the direction of rotation of the drum is such that the bands arrive at the transfer position from the opposite direction to the products.

2. A banding apparatus as claimed in claim 1, wherein the drum is formed with flat sides to support the bands over a substantial part of their axial length.

3. A banding apparatus as claimed in claim 1 or 2, wherein the bands are held on to the drum by means of a vacuum.

4. A banding apparatus as claimed in any preceding claim, wherein the supply of bands comprises a roll of flattened tubular stock having creases along its opposite edges, a former for opening the stock from the roll into a cylinder and at least partially re-flattening the cylinder with the original creases adjacent one another, rollers for advancing the re-flattened stock towards the drum and a cutter for severing a band of the desired axial length from the stock. 10

5. A banding apparatus as claimed in claim 4, wherein the distance between the drum and the cutter is adjustable.

6. A banding apparatus as claimed in any preceding claim, for use with a conveyor on which products are transported in an upright attitude, wherein at the transfer position a band to be transferred to one of the products on the conveyor is held by the drum with its axis at substantially 30 to the vertical and its open mouth in the lo path of the top of the product on the conveyor.

7. A banding apparatus as claimed in claim 6, wherein the drum has three sides and is indexed by 120 between per band.

8 A banding apparatus as claimed in claim 6, wherein the drum has six sides and is indexed by 60 per band.

9. A banding apparatus as claimed in any one of claims 1 to 5, for use with a conveyor supporting products in a horizontal attitude, wherein at the transfer position the bands are positioned horizontally by the drum in the path of the products.

10. A banding apparatus as claimed in claim 9, wherein the drum has four sides and is indexed by 90 between consecutive products.

11. A banding apparatus constructed arranged and adapted to operate substantially as herein described with reference to and as illustrated in the accompanying drawings.