FOLDING DEVICE FOR MANUFACTURING A PACKAGE FROM A SHEET OF FOLDABLE MATERIAL
The invention relates to a folding device for folding a packaging, which is substantially closed in its peripheral direction, from a sheet of a foldable material, comprising a surface which is horizontal in 5 the situation of use and which is provided with an elongate channel with a predetermined width and depth for receiving and deforming a sheet of a foldable material laid on this surface, wherein the width and the depth of the channel are determined by the peripheral 0 dimensions of the packaging for folding.
A so-called folding table is known wherein a channel or recess is formed in the upper surface of this table, the dimensions of this channel corresponding with the peripheral dimensions of a packaging to be folded on 5 this folding table.
Using the known folding table a packaging is folded from a sheet of a foldable material, for instance corrugated board, which is cut into a predetermined form and provided with crease lines, wherein a central part 0 of the sheet is bounded by a pair of parallel first crease lines, the mutual distance of which is just smaller than the width of the channel, and wherein at least one side part adjacent to the central part of the sheet is bounded by a first crease line and a second 5 crease line parallel thereto at a mutual distance which is just smaller than the depth of the channel. In order to fold a packaging, the sheet is laid on the table and over the channel in a manner such that the first crease lines extend just inside the channel. The content for 0 packaging (one or more goods) is then placed on the central part of the sheet and the sheet with content is pressed manually into the channel, wherein the side parts adjacent to the central part are folded round the contents along the crease lines and (in the case of a
packaging of triangular or square cross-section) closing parts adjacent to one or both side parts are then folded over the respective side part or over each other. The thus formed packaging with content must then be closed. For this purpose the packaging with content is pushed along in the channel to a bundling machine, and the packaging is bundled, i.e. wrapped with string or plastic cable.
The known folding table for folding and bundling has the inherent drawback that the packaging bundled therewith is less compact and closed than a packaging which is closed wholly by hand and with glue or self- adhesive tape. A folding table provided with a bundling machine moreover takes up more space in longitudinal direction, which is particularly disadvantageous in the case of long packages, for instance for sunblinds or other long objects.
It is an object of the invention to provide a folding table with which it is possible to at least largely fold a packaging mechanically in rapid and simple manner, to provide the thus folded packaging with the intended content and to further fold down the thus filled packaging and close it using an applied glue.
It is a further object to provide a folding table which is compact.
It is another object to provide a folding table which is suitable for providing with means for mechanically closing a folded packaging provided with glue. These objects are achieved with a folding table of the type stated in the preamble, wherein according to the invention the channel is provided with engaging means displaceable in vertical direction for engaging a sheet laid on the surface and extending over the channel and for receiving and deforming said sheet in the channel by downward displacement of said engaging means .
In an embodiment of a folding table according to the invention the engaging means comprise at least one suction nozzle, which is for instance provided in a vacuum conduit extending in the channel and displaceable in vertical direction.
In a folding table which is provided with such a vacuum conduit with suction nozzle it is possible to fold a sheet in simple manner by placing the vacuum conduit with suction nozzle high in the channel such that the sheet for folding can be laid on the suction nozzle, so that the suction nozzle can engage the sheet by creating a vacuum in the vacuum conduit, whereafter the vacuum conduit with suction nozzle is displaced in downward direction, wherein the sheet is received in the channel while being simultaneously deformed.
In this latter embodiment the vacuum conduit preferably provides on its upward directed side an elongate surface extending horizontally in longitudinal direction of the channel, more preferably the vacuum conduit comprises a tube of rectangular cross-section. The elongate surface on the upper side of the vacuum conduit forms a stable support surface for the central part of a sheet laid on the folding table. In another embodiment the at least one suction nozzle can be closed by means of a contact valve.
A contact valve is a valve which closes a vacuum conduit and which is opened upon contact with a suitable surface, for instance that of a cardboard sheet.
The advantages of a folding device are particularly manifest in an embodiment which is provided with at least one folding member, extending along the channel and displaceable in transverse direction to a position above the channel, for folding a wall part extending outside the channel of an at least partly deformed sheet received in the channel.
Not only are the side parts of a flat sheet that are adjacent to the central part folded in mechanical
manner with such a folding device, so is the closing part adjacent to a side part extending along this side of the channel where the at least one folding member is provided. In the latter embodiment a folding member preferably comprises a strip flush-mounted in the surface, which strip is more preferably pivotable on an axis in longitudinal direction on its side remote from the channel . An embodiment of a folding device according to the invention is provided with a glue applicator for applying glue at predetermined positions on an at least partially deformed sheet received in the channel.
Yet another embodiment of a folding device, which is particularly suitable for the folding of packages of different dimensions, is provided with width and/or depth-adjusting means for adjusting respectively the width and the depth of the channel.
The invention will be elucidated hereinbelow on the basis of embodiments, with reference to the drawings.
In the drawings :
Fig. 1 shows a perspective view of an embodiment of a folding table according to the invention, and
Fig. 2a-2h show in a schematic view in cross- section the folding table shown in fig. 1 on which a flat sheet of cardboard for folding and an object for packaging are placed, at different stages of the folding.
Corresponding components are designated in the figures with the same reference numerals.
Fig. 1 shows a folding table 1 with an upper surface 2, 21, 3, 22 which rests on a frame 4. The upper surface 2, 21, 3, 22 is assembled from static screening surfaces 2, 3 and displaceable surface parts 21, 22 which bound a channel 5, in which is received a vacuum tube 6 of rectangular cross-section displaceable in vertical direction, which is provided on its upper side
with contact valves 7. The width of channel 5 is adjustable in that the displaceable surface parts 21, 22 are horizontally displaceable in a direction transversely of channel 5 using spindles driven by a hand wheel operation 9. The displaceable surface parts 21, 22 are covered on their side remote from channel 5 by the closely fitting thin screening surfaces 2, 3 not coupled to surface parts 21, 22, wherein surface parts 21, 22 and screening surfaces 2, 3 together provide a flat surface for depositing thereon a sheet for folding, irrespective of the position of displaceable surface parts 21, 22 relative to static surface parts 2, 3. The depth of channel 5 is adjustable in that the vacuum tube 6 is vertically displaceable by means of a depth- adjusting device with spindles driven by a hand wheel operation 13. The displaceable surface parts 21, 22 form a pair of folding members, generally designated by the name folding knives. Folding members 21, 22, the operation of which will be further elucidated below in the description of fig. 2, are driven by horizontal pneumatic cylinders 8. Vacuum tube 6, which performs an up and downward movement in channel 5 during folding of a sheet, is driven by vertical pneumatic cylinders 12. Folding table 1 further comprises a vacuum pump 14 with filter 15 and vacuum conduit 16, which is coupled to vacuum tube 6, a housing 10 for an electronic control circuit for vacuum pump 14, vacuum valves (not shown) and the control system for vacuum tube 6 and folding members 21, 22. Folding table 1 is provided with fixing elements 17 for fixing to for instance a cardboard cutting machine for cutting sheets with the desired dimensions from endless cardboard. Not shown is a glue applicator for applying glue to parts for glueing of the sheets to be folded. Fig. 2a-2h show folding table 1 in a situation where a flat sheet of cardboard 19 for folding and an object 20 for packaging are placed thereon, at different
stages of folding. The figure shows folding members 21, 22 flush-mounted in upper surface 2, 3 in a rest situation. The operation of folding table 1 is as follows . a. A flat sheet 19 is supplied on upper surface 2, 21, 3, 22 by a cutting machine (not shown) coupled to folding table 1, whereafter an object for packaging 20 is placed on sheet 19 just above channel 5. The tube 6 provided with contact valves (not shown) is moved upward and sheet 19 is sucked fixedly on vacuum tube 6 by the contact valves (Fig. 2a) . b. Folding members 21, 22 are rotated upward by respective control members 23, 24 coupled thereto about respective axes 25, 26, as a result of which side parts 27, 28 of sheet 19 are folded up (Fig. 2b) . c. Vacuum tube 6 is pulled downward, as a result of which the sheet 19 with object 20 sinks into the channel and side parts 27, 28 are folded further upward (Fig. 2c) until d. vacuum tube 6 has reached its lowest position, wherein only closing parts 29, 30 of sheet 19 still protrude above upper surface 2, 3 (Fig. 2d) . e. A first folding member 22 is subsequently displaced to a position above channel 5, as a result of which a first closing part 30 of sheet 19 is folded over object 20 (Fig. 2e) , whereafter f. the first folding member 22 is rotated downward about its longitudinal axis 26 by control member 24 and closing part 30 is folded onto object 20 (Fig. 2f) . g. The second folding member 21 is then displaced to a position above channel 5 by control member 23, as a result of which the second closing part 29 of sheet 19, which is provided beforehand with glue at a position suitable for this purpose on the side facing the first closing part 30, is folded over the first closing part 30 (Fig. 2g) , whereafter
h. the second folding member 21 is rotated downward about its longitudinal axis 25 by control member 23 while the first folding member 22 is simultaneously retracted and the second closing part 29 is folded onto the first closing part 30 and glued fixedly thereon (Fig. 2h) .
After glueing of the second closing part 29 onto the first closing part 30, the second folding member 21 is retracted, the vacuum tube 6 with packaged object 20 is displaced upward, the vacuum in tube 6 is released and the packaged object 20 is removed from folding table 1, whereafter it is available for packaging of the following object 20 in the described manner.