GB2098538A - Apparatus for processing carton blanks - Google Patents

Abstract

A transfer member (19) transfers carton blanks (15) one at a time from a magazine (14) to an indexable forming tool (12), and the tool (12) then carries the blank to a station removed from the magazine for adhesive treatment, for example to apply a hot melt adhesive or to activate a heat-activatable adhesive already provided on the blank. Each carton blank (15) is received by the transfer member from a side (17) of the magazine which lies in a plane (24) inclined to the vertical and is transferred to a side (18) of the forming tool (12) which lies in a vertical plane (23). The transfer member (19) is pivotable about an axis (22) which may lie substantially at the intersection of these two planes, to transfer each blank from the magazine (14) to the forming tool (12). <IMAGE>

Description

SPECIFICATION Apparatus for processing carton blanks The present invention relates to apparatus for processing carton blanks, and is concerned particularly with the removal of carton blanks from a carton magazine and the subsequent treatment of the removed blank.

In a known technique of feeding single carton blanks to the forming stations of a carton erecting machine, a stack of such blanks is stored in a vertical magazine. Single blanks are then extracted from the base of the stack by a vacuum system and are transferred to the forming station.

The vertically disposed magazine is associated with means for applying patterns of adhesive to selected areas of the lowermost blank immediately prior to its being extracted from the magazine by the vacuum system.

Where the carton erection system comprises a series of forming blocks or mandrels onto which a blank is held while it is formed into a carton, the vacuum may be applied by vacuum cups contained in faces of the forming blocks. In this system the magazine is lowered so that the lowermost blank is pressed onto the vacuum cups and is then raised again so that the lowermost blank is extracted by the negative pressure.

The above-described technique suffers from a number of disadvantages, viz:- 1. Since the magazine must be disposed vertically for reasons of adhesive application, it is relatively difficult to place fresh supplies into the magazine. In addition, due to the height of the stack above the floor, the reservoir of carton blanks is limited and therefore requires constant replenishment.

2. If the adhesive is of the hot melt type, which is normal, the lowermost blanks in the magazine take up heat from the adhesive tank and, especially after a stop period, these heated blanks tend to become warped and difficult to form or seal correctly. Some form of forced air cooling system is found to be necessary to disperse the warm air.

3. The weight of a stack of carton blanks piled vertically will vary widely depending on the quantity of blanks in the magazine from time to time. This weight variation will affect the force required to extract a single blank from the base of the stack, and with certain shapes of blank and grades of carton board this may cause downtime due to inconsistencies in feeding blanks to the forming station.

It is an object of the present invention to overcome these particular disadvantages.

According to the invention, apparatus for processing carton blanks comprises a forming tool indexable between a plurality of stations, a carton blank magazine disposed at one of the stations, adhesive treatment means disposed at a station displaced from the magazine, and transfer means for transferring carton blanks one at a time from the magazine to the forming tool when the latter is disposed at said one station, the transfer means including a pivotable transfer member having gripping means thereon which grips the carton blank during its transference from the magazine to the forming tool.

Since the carton blank magazine is at a station removed from the adhesive treatment station, blanks held in the magazine are not damaged by heat and accordingly it is not necessary to provide some form of forced air cooling. The adhesive treatment may comprise the application of an adhesive to selected areas of the carton blank, or alternatively the activation of an adhesive which has been pre-applied to the blank.

In a preferred example of the invention, the magazine and the forming tool have respective sides which, when the forming tool is disposed at said one station, face one another and are relatively inclined, and the transfer member is pivotable about an axis disposed substantially at the intersection of planes which pass through said sides respectively. Most preferably, said sides are relatively inclined in a vertical plane. For example, said side of the forming tool can lie in a vertical plane, while the magazine can be inclined so that its side lies in a plane inclined to the vertical. Such inclination of the magazine serves to reduce the variations in pressure between full and emptry magazine conditions, since the main weight component is distributed onto members of the magazine which support the carton stack. This in turn enables greater carton blank storage to be provided.

Desirably, the transfer member is bifurcated and includes two generally parallel arms whose lateral spacing is such that they can pass on opposite sides of the forming tool, respectively, and the gripping means is provided on said arms.

The apparatus may also comprise pressure means which is operable to press a carton blank against the forming tool to flatten the blank, the pressure means advantageously being disposed at said one station so that the forming tool is indexable relative thereto. The pressure means may for example comprise pressure plates pivotable about respective axes which are positioned to opposite sides of the transfer member and which are oriented generally perpendicular to the pivot axis of the latter.

Conveniently, the forming tool is indexable about a rotation axis and is radially fixed relative to said axis.

The gripping means may take the form of vacuum cups. The forming tool may also have at least one vacuum cup which can be activated to grip a carton blank transferred thereto by the transfer means.

Although it is possible for only one forming tool to be provided, it is preferred to employ a plurality of such tools which are indexed in unison.

The invention will now be further described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of apparatus according to the invention for erecting cartons from carton blanks; Figure 2 is a side elevational view of the apparatus shown in Figure 1; and Figure 3 is an enlarged plan view of part of the apparatus shown in Figures 1 and 2.

The illustrated apparatus comprises a turret 10 which can be rotatably indexed about a horizontal axis 11 and which mounts a plurality of forming tools 1 2 in angularly spaced relation about the axis 11. In the illustrated embodiment, four such forming tools 12 are provided on a generally cruciform support 13, although only two of the tools are actually shown. Each of the forming tools 12 is radially fixed relative to the axis 11, and can be indexed by the turret 10 between a plurality of stations which are angularly spaced around the axis 11.

Disposed at one of these stations is a magazine 14 (shown in chain-dotted lines in Figure 1) which holds a stack of carton blanks 15, the magazine being inclined to the vertical. A transfer device 1 6 operates to transfer the carton blanks 1 5 one at a time from a leading side 17 of the magazine 14 onto a radially outwardly facing side 1 8 of each forming tool 12 in turn as the turret 10 is indexed.

The transfer device 1 6 comprises a bifurcated transfer member 1 9 having a pair of generally parallel arms 20 which are laterally spaced apart sufficiently to allow them to pass on either side of each forming tool 12 when the latter is disposed at the aforesaid station. A pair of vacuum cups 21 are provided on each arm 20 and face outwardly of the axis 11. The transfer member 1 9 is pivotable about a horizontal axis 22 which lies substantially at the intersection between a vertical plane 23 passing through the side 1 8 of the forming tool 12 and an inclined plane 24 passing through the side 17 of the magazine 14, the planes 23 and 24 being indicated by chain-dotted lines in Figure 2.

In order to transfer a carton blank 1 5 from the magazine 14 to the forming tool 12, the transfer member 19 is pivoted to the position shown in Figure 2 wherein the vacuum cups 21 engage the leading blank in the magazine. The transfer member 1 9 is then swung in the direction of arrow 25 to remove the blank from the magazine 14 and bring it into vertical alignment with the side 18 of the forming tool 21. Vacuum cups 26 provided in the side 1 8 are then actuated to grip the blank 15 while the vacuum cups 21 on the transfer member 1 9 are de-activated to release the blank. The carton blank is thus now held on the forming tool 12.

Where the carton blank includes a number of fold lines, there is a possibility that it may not be held in a planar condition on the forming tool 12.

In order to bring the blank into such a condition, a pair of pressure plates 27 are provided which are rotatable about respective vertical axes 28 disposed to opposite sides of the transfer member 1 9. During transference of a blank to the forming tool 12, the plates 27 are disposed in the positions shown in Figures 1 and 2. After the blank has been placed on the tool 12, the plates 27 are rotated so that they come into contact with the reverse side of the blank and press the latter into a flat condition, as indicated in Figure 3. The pressure plates 27 are then reverse rotated back to their starting positions.

After the transfer of a carton blank from the magazine 14 to one of the forming tools 12, the turret 10 is indexed in the direction of arrow 29 in Figures 2 and 3 to bring the blank to a further station where it is subjected to adhesive treatment. Such treatment may take the form of the application of an adhesive to selected areas (such as flaps) of the blank, or alternatively may involve activating an adhesive which has been pre-appllied to the blank. Since this treatment is performed at a station removed from the magazine 14, the carton blanks held in the latter will not be adversely affected by any heat generated for the purpose of the adhesive treatment. Thereafter, flaps of the blank are folded to erect the carton.

It will be appreciated that various modifications can be made to the apparatus described above.

For example, although the transfer member 19 and the forming tools 12 are each shown as having four vacuum cups, a different number from this can be employed if desired. In addition, the turret 10 may comprise other than four forming tools 12: in certain circumstances, it may be possible to provide only one such forming tool which is indexed about the axis 11.

Claims (12)

1. Apparatus for processing carton blanks, comprising a forming tool indexable between a plurality of stations, a carton blank magazine disposed at one of the stations, adhesive treatment means disposed at a station displaced from the magazine, and transfer means for transferring carton blanks one at a time from the magazine to the forming tool when the latter is disposed at said one station, the transfer means including a pivotable transfer member having gripping means thereon which grips the carton blank during its transference from the magazine to the forming tool.

2. Apparatus as claimed in claim 1, wherein the magazine and the forming tool have respective sides which, when the forming tool is disposed at said one station, face one another and are relatively inclined, and the transfer member is pivotable about an axis disposed substantially at the intersection of planes which pass through said sides respectively.

3. Apparatus as claimed in claim 2, wherein said sides are relatively inclined in a vertical plane.

4. Apparatus as claimed in claim 3, wherein said side of the forming tool lies in a vertical plane, and said side of the magazine lies in a plane which is inclined to the vertical.

5. Apparatus as claimed in any preceding claim, wherein the transfer member is bifurcated and includes two generally parallel arms whose lateral spacing is such that they can pass on opposite sides of the forming tool, respectively, and the gripping means is provided on said arms.

6. Apparatus as claimed in any preceding claim, further comprising pressure means operable to press a carton blank against the forming tool to flatten the blank.

7. Apparatus as claimed in claim 6, wherein the pressure means is disposed at said one station and the forming tool is indexable relative thereto.

8. Apparatus as claimed in claim 7, wherein the pressure means comprises pressure plates pivotable about respective axes which are positioned to opposite sides of the transfer member and which are oriented generally perpendicular to the pivot axis of the latter.

9. Apparatus as claimed in any preceding claim, wherein the forming tool is indexable about a rotation axis and is radially fixed relative to said axis.

10. Apparatus as claimed in any preceding claim, wherein the gripping means is in the form of vacuum cups.

11. Apparatus as claimed in any preceding claim, wherein the forming tool has at least one vacuum cup which can be activated to grip a carton blank transferred thereto by the transfer means.

12. Apparatus as claimed in any preceding claim, comprising a plurality of such forming tools which are indexable in unison.

1 3. Apparatus for processing carton blanks, substantially as hereinbefore described with reference to the accompanying drawings.