CONVEYOR FOR CONTAINERS WITH MAGNETIC RETAINING MEANS
The present invention relates to conveyor apparatus for containers and in particular, but not exclusively, to conveyor apparatus for food production containers conveying baking tins from an upright condition to an inverted condition.
For reasons of good hygiene practice, plant bakers prefer to store straps of baking tins upside-down when not in use to avoid potential contaminants collecting inside the tins. This is easy to achieve on manually operated plants, but more difficult with automated storage equipment. In one known arrangement an indexing star wheel rotates through 90° for each tin presented to it so that each tin is eventually inverted by way of further incremental movements of the '.wheel. This arrangement is a somewhat crude device which has significant cycling time limitations.
The present invention seeks to provide an alternative arrangement.
According to the present invention there is provided conveyor apparatus for containers comprising conveyor means and magnetic field generating means, the apparatus being so arranged that, in use, the magnetic field generating means attracts a container towards the conveyor means, and a driven portion of the conveyer means is received by the attracted container, and the conveyor means is operative to convey the container to a desired location by rotating the container to a desired orientation.
The conveyor means is desirably arranged to convey the food production container from a substantially upright condition to a substantially inverted condition.
The conveyor means may, in addition or alternatively, be arranged to convey the container from a substantially inverted condition to a substantially upright condition.
The container is preferably a food production container.
The food production container preferably comprises baking containers.
In a highly preferred embodiment the conveyor apparatus is adapted to convey a plurality of integral baking tins from an upright condition to an inverted condition.
Preferably the magnetic field generating means is provided radially inwards of the conveyor means.
The driven portion of the conveyor means is preferably configured to be received in the interior space defined by the container.
The conveyor apparatus is preferably arranged such that the driven portion of conveyor means comprises a peripheral portion of the conveyor means
Preferably the conveyor means comprises a rotatable member. The conveyor means may comprise two or more axially spaced rotatable members .
The magnetic field generating means may be provided laterally between the axially spaced rotatable members. In an alternative embodiment however the rotatable members may be provided with magnetic field generating means.
The conveyor means desirably defines a substantially circular periphery.
In a preferred embodiment, the conveyor means comprises a pulley which is driven by a belt, a further magnetic field generating means being provided behind that portion of the belt which is upstream of the pulley and adjacent to the pulley. Such an arrangement holds the (upright) container captive with the belt and as the belt moves towards the pulley the container is accordingly brought into engagement with the pulley.
Two embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings:
Figure 1 is a schematic vertical cross-section of a first embodiment of the invention,
Figure 2 is a schematic plan view on section 2-2 of the embodiment shown in Figure 1,
Figure 3 is a schematic vertical cross-section of a second embodiment of the invention, and
Figure 4 is a schematic plan view on section 4-4 of the embodiment shown in Figure 3.
With reference to Figures 1 and 2, there is shown conveyor apparatus 1 which comprises a feed conveyor 2, an inverter conveyor 3 and a discharge conveyor 4. The conveyor apparatus 1 is operative, in use, to transfer baking tins 5 in an upright condition on the feed conveyor 2 to an inverted condition as they are conveyed away to storage facilities on the discharge conveyor 4.
The inverter conveyor 3 comprises two axially spaced pulleys 6 which are mounted on a common axle 7. The pulleys are each driven by
respective drive belts 8, and are arranged to engage with substantially 180° of the arcuate peripheries 9 of the respective pulleys 6. The belts 8 are additionally guided by two pairs of pulleys 10 and 11 , the pulleys 11 being mounted on a common axle 12. Motive means (not shown) is connected to the axle 12, and when such motive means is operated the pulleys 6, 10 and 11 are caused to rotate.
The inverter conveyor 3 further comprises two magnetic field sources 15 and 16, which are disposed transversely between the pulleys 6, the field source 16 being of substantially semi-annular formation and disposed radially inwards of the peripheries 9 of pulleys 6. The magnetic field source 15 is disposed higher than those portions 17 of the belts 8 which are upstream of the pulleys 6 and adjacent to said pulleys 6.
In use the apparatus 1 operates as follows. Multiple integral baking tins 5 (known as straps of baking tins) which are joined at their side rims are advanced towards the inverter conveyor 3 on the feed conveyor 2. On reaching a position which is below the magnetic field source 15 the tins are magnetically attracted upwards and are held captive against the belts 8. As the belts 8 advance the tins are brought into engagement with the peripheries 9 of the pulleys 6. In particular, arcuate portions of the peripheries of pulleys 6 protrude into the interior space of those tins which are at the distal ends of each strap of tins 5. This can clearly be seen in Figure 1 in which the strap 5a receives a portion of the peripheries 9. Advantageously the protrusion of the peripheries of the pulleys 6 into the interior spaces of the straps provides positive location and drive for each strap of tins .
As the straps of tins come into engagement with the pulleys 6 they are then held captive against the peripheries of said pulleys by the action of the magnetic field created by the magnetic field source 16. The straps of
tins 5 are thus rotated through substantially 180° in a fixed position relative to the pulleys 6.
Once the straps 5 have been rotated through 180° they are in a substantially inverted condition. Portions 18 of the belts 8 are arranged to provide a 'bridge' between the pulleys 6 and the discharge conveyor 4. Once transferred to the discharge conveyor 4 the straps of tins 5 are transferred to a store.
Figures 3 and 4 show a second conveyor apparatus 1 ' which is very similar to that of Figures 1 and 2 except that the feed conveyor 2 has been replaced by a right-angle feed conveyor 20 and a support 21, and the pulleys 11 have been moved rearwards to allow the inclusion of a third magnetic field source 22. In Figures 3 and 4, like reference numerals to those in Figures 1 and 2 denote like features.
Straps of baking tins 5 are fed longitudinally onto the support 21 by the right-angle conveyor 20. On reaching the support 21 the straps 5 are attracted upwards onto belt 8' first by magnetic field source 22 and subsequently by magnetic field source 15. The method of operation of the conveyor apparatus 1 ' is then identical to that of conveyor apparatus 1.
In an alternative embodiment the pulleys 6 are replaced by a drum which is provided with magnetic field generating means. In such an embodiment the drum would preferably be provided with a 'field' of outwardly extending location protrusions which are adapted to be received in the interior space (s) defined by the baking tins or other food production containers to be inverted.
In a further embodiment, the pulleys 6 are not connected by a common axle. Furthermore the pulleys 6 may be driven either directly or indirectly.
Although in the embodiments described the pulleys 6 protrude into the endmost tins, the pulleys may be arranged to extend into any of the other tins of a strap.
It will be appreciated that the inventive apparatus may equally be employed to convey food production containers in storage from an inverted condition to an upright condition for use in a food production process.
Although specific mention has been made to food production containers, other industrial environments which use open containers which need, say, to be inverted (say for storage) from an upright condition (or vice versa), may also find advantage in using apparatus hereinbefore described. By Open container' is meant a container having a base, one or more upstanding side walls and an open upper end.