GB2131763A - Apparatus for palletising, layer by layer on relative pallets, objects of various kinds originating from separate channels - Google Patents

Abstract

The invention provides an apparatus for palletising, layer by layer on relative pallets 21, objects of various kinds originating from separate channels, comprising a single device 10 for forming individual layers of objects and containing a pallet loading station, a trolley 20 carrying a number of pallets at least equal to the number of kinds of objects and mobile in order to move a pallet into the loading station when required, a conveyor 13 connecting the object arrival channels to the layer forming device in order to feed this latter as required with objects originating from one of the channels in the required number for forming a layer, an empty pallet feeder 22 and a full pallet removal device 23, these being disposed in-line, said line passing through the loading station, at which continuity is created by a motorised roller table 38. This roller table can be lowered into a position below the pallet support surface of said mobile trolley. <IMAGE>

Description

SPECIFICATION Apparatus for palletising, layer by layer on relative pal lets, objects of various kinds originating from separate channels This invention relates to an apparatus for palletising, layer by layer on relative pallets, objects of various kinds originating from separate channels.

The objects of various kinds to be palletised can be various types of packages, such as cartons, parcels, boxes, bags etc., which can also be of different dimensions, or alternatively articles, products and the like suitable for palletising layer by layer.

The objects arriving in any one channel are all of the same type, for example, the same product, while the objects arriving in any other channel can be of a different type, for example a different product.

It is often required to palletise, layer by layer on relative pallets using a single apparatus, objects of various kinds originating from separate channels at any rate of arrival which is often different from the various channels, but being careful to form layers containing only objects of the same type on any one pallet. The number of pallets available must therefore be equal to the number of channels from which objects of different types arrive.

Apparatus are known able to palletise objects originating from at least two separate channels.

Such apparatus comprise a single device for forming individual layers of objects to be loaded on to pallets and containing a pallet loading station, a trolley carrying a number of pallets at least equal to the number of types of objects and mobile in order to move a pallet into the loading station when required, a conveyor connecting the object arrival channels to the layer forming device in order to feed this latter as required with the correct number of objects originating from one of the channels for forming a layer, an empty pallet feeder and a full pallet removal device. The entire apparatus is provided with suitable controls for automating the various operations. These operations are generally such that as the objects arrive in the separate channels they are firstly accumulated in these channels.As soon as one of the channels is filled with a predetermined number of relative objects, sufficient to form at least one layer on a respective pallet, this channel is opened in order to allow the number of objects for forming one layer to discharge on to said conveyor, which then feeds the objects to the layer forming device.

Simultaneously, the pallet support trolley is moved in such a manner that the pallet which is to receive the objects of said specific channel is brought into the loading station. When a layer of these objects has been loaded on to the relative pallet, the operating cycle is repeated for the channel which was next filled, and so on in accordance with the flow of different objects arriving in the respective channels.

In this manner it is possible to maximise the utilisation of the apparatus operating capacity.

The operations are repeated until the maximum layers of objects is reached on each pallet. As soon as a pallet has been completely loaded with its specific objects, it is removed by means of the removal device and replaced by an empty pallet.

In order to enable the empty pallets to be positioned on said pallet support trolley and the full pallets to be removed, the pallet support trolley in known apparatus of the aforesaid type is provided with a number of motorised conveyors equal to the number of pallets to be simultaneously carried on said trolley, each of said motorised conveyors being able to receive one pallet from the empty pallet feeder and, after the pallet has been filled with the scheduled number of layers of objects, to move the full pallet perpendicularly to the direction of movement of the trolley in order to feed it to a removal line. It is apparent that because of this, each motorised conveyor disposed on the mobile pallet support trolley requires mobile electrical and/or pneumatic connection lines for operating the motors of said conveyors and for operating relative control members.This results in considerable constructional and structural complexity of the pallet support trolley and the means required for controlling and operating it, and of the respective conveyors for the individual pallets.

The object of the present invention is therefore to obviate this drawback and to structurally and operationally simplify, and increase the safety of, the pallet support trolley with its empty pallet positioning system and full pallet removal system, in a palletising apparatus of the aforesaid type.

This object is attained according to the invention by making the support surface for the pallets on said trolley mobile by means of at least two longitudinal members of a frame forming the trolley, a-nd disposing in the loading station of the device which forms individual layers of objects motorised roller table which can be moved from a raised position in which it creates continuity between the empty feeder and the full pallet removal device, to a lowered position below said pallet support surface on the pallet support trolley.

In this manner, the pallet support trolley is considerably simplified as it no longer comprises mobile members such as the motorised conveyors for the individual pallets, so that mobile connection lines are also not necessary for operating said mobile members. The trolley can be formed from a simple frame, of which the longitudinal members constitute the pallet support surface, and for loading the empty pallets and unloading the full pallets a stationary device is used constituted by a simple motorised roller table which can be moved upwards and downwards.

The characteristics and advantages of the invention will be more apparent from the description given hereinafter of one embodiment of the apparatus according to the invention with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic plan view of the entire apparatus; Figure 2 is a partial side elevation on the line Il-Il of Figure 1; Figure 3 is a plan view of the lower central part of the apparatus, with some parts removed; Figures 4 and 5 are sections on the line IV--IV and V-V of Figure 3.

The illustrated apparatus firstly comprises a device for forming individual layers of objects to be deposited on a pallet. This device for example can be of the known type as described in detail and illustrated in the U.K. Patent No. 2048208 granted on February 2, 1 983 of the present applicant.

The various parts of this device for forming layers of objects are not described herein, and reference should be made to the aforesaid patent application therefor.

It is sufficient to note that the device indicated overall by 10 in Figures 1 and 2 comprises, mobile vertically along guide columns 11, a frame 12 which supports the means on which individual layers of objects are formed as required, and then enables the entire layer of objects to be unloaded on to an underlying pallet 4, on to another layer of objects previously loaded on to the pallet. Below the vertically mobile frame 12 there is the pallet loading station. The objects to be grouped into individual layers to be palletised reach the layer forming device 10 at a raised level, up to which the frame 12 has to be lifted each time after the previously formed layer has been deposited on to a pallet.At this raised level there is provided an at least partly motorised conveyor line, indicated overall by 13, for the arriving objects to be fed to the layer forming device, and various channels abut against this conveyor line, namely four channels 14, 15, 16, 17 in the present example, which are connected to a like number of production lines (not shown) for different objects or products. At their ends abutting against the conveyor line 13, the individual arrival channels 14-1 7 are closed for example by doors diagrammatically indicated by 1 8 in Figure 1, and which can be individually opened by suitable controls.When one of the doors 1 8 is opened, the objects 1 9 which in the meantime have accumulated in the relative arrival channel can be discharged, for example by gravity or by pushing, on to the conveyor layer 13 which can be suitably motorised in order to transfer the objects into the layer forming device 10. After discharging a determined number of objects, necessary and sufficient to form one layer, the door 1 8 of the channel concerned is again closed.

In a lower horizontal plane there is provided a linearly mobile trolley, indicated overall by 20, designed to move a number of pallets 21 at least equal to the number of different objects or products to be palletised and thus to the number of arrival channels for said objects. In this manner, each position for a pellet on the trolley 20 is correlated with a determined one of the channels 14-1 7 for different arriving objects, in the sense that the objects originating from any one channel are always loaded on to the pallet disposed in the correlated position on the trolley 20.

The trolley 20 is mobile along its longitudinal axis relative to the layer forming device 10 so as to be able at any required time to move a pallet 21 (i.e. that relative to the objects originating from the channel which in that moment is to be discharged) into the loading station below the frame 12.

Transversely and perpendicular to the direction of movement of the trolley 20 there are disposed, in a line passing through the loading station, an empty pallet feed device indicated overall by 22, and a full pallet removal device indicated overall by 23. The empty pallets fed by the device 22 must be positioned on the trolley 20, while the full pallets formed on the trolley 20 must be transferred to the removal device 23.

The present invention relates substantially to the pallet support trolley 20 and the pallet positioning and removal system, and these parts are described in detail hereinafter with particular reference to Figures 3-6.

The trolley 20 is constituted in practice by a frame formed from three longitudinal members 24,25, 26 made mutually rigid by a set of crossmembers 27. The longitudinal members are in the form of flat sections disposed standing up so that their upper ends form the support surface for the pallets 21, whereas their lower ends slidably rest on a set of rollers 28 carried by transverse shafts 29 which are supported freely rotatable in fixed supports. The rollers 28 thus form the slide guides for the trolley 20.

Rigidly fixed on the outside of the longitudinal side members 24, 26 of the frame for the trolley 20 there are longitudinal racks 30, 31 with which there engage pinions 32, 33 fixed to a transverse shaft 34 supported freely rotatable ins fixed supports, said shaft 34 carrying a sprocket 35 for a chain 36 drivable by a motor 37 (see Figure 3).

This is a motor fixed to the framework which can be made to rotate in either direction on command in order to cause the trolley 20 to move linearly in one direction or the other by means of the described transmission. The movement and positioning of the trolley 20 can be suitably controlled by an encoder (not shown) so as to make it superfluous to arrange micro-switches or other elements along the trolley path.

It should be noted that the trolley 20 is in the form of a simple frame which carries neither mobile members nor control members. In the pallet loading station below the mobile frame 12 of the layer forming device 10 and within the range of the mobile trolley 20 there is provided a motorised roller table, indicated overall by 38, which can be moved overall vertically. Said roller table is formed from a framework with side walls 39, 40 connected together by tie bars 41 and angle base sections 42, 43, which rest lowerly on rollers 44 idly supported at the end of arms 45.

The side walls 39, 40 comprise in their upper part an open cavity 46 (Figure 5) into which the central longitudinal member 25 of the trolley 20 can be inserted, the length of said walls being such that they remain within the space defined by the longitudinal side members 24, 26 of said trolley.

The arms 45 of the support rollers 44 of the framework for the roller table 38 are provided in pairs fixed on to two transverse shafts 47, 48 supported freely rotatable in fixed supports (see Figures 3 and 4). Said transverse shafts 47, 48 each carry a further arm 49, and the two arms 49 are connected together by an articulated rod 50.

Finally, the shaft 47 carries a further arm 51, to the end of which is hinged the rod 52 of a pneumatic cylinder 53, which is itself hinged to a fixed point of the frame (Figure 5). It is apparent that on moving the rod 52 of the cylinder 53, the articulated parallelogram formed by the shafts 47, 48, the rod 50 and the arms 49 induces angular movements of the arms 45 which by way of the rollers 44 support the framework of the roller table 38, thus causing said roller table to move vertically (in Figures 4 and 5 said roller table is shown in its lowered position).

To enable these movements to be correctly guided vertically, the framework comprises lowerly projecting bushes into which fixed pins 54 are inserted (as shown in Figure 5).

The framework upperly carries a set of parallel rollers 55 which are rotatably supported at their ends by the side walls 39 and 40, which rollers 55 constitute the actual roller table and can be rotated about their axis either all in one direction or all in the opposite direction.

The rollers 55 are driven by a motor 56 which can be operated in both directions of rotation. On the shaft of said motor 56 there is fixed a sprocket 57 which constitutes the drive sprocket for an endless chain 58 (see Figure 5 in particular) which is guided over a set of deviation sprockets 59 and pin ions 60. With each roller 55 there is rigid a pinion 60 at that end supported by the wall 39.

When the chain 58 is driven in one direction or the other by the motor 56, it rotates all the rollers 55.

When the roller table 38 is in its raised position, it creates continuity between the empty pallet arrival line and the full pallet removal line, whereas when it is in its lowered position it rests below the pallet support surface of the longitudinal members 24, 25, 26 of the trolley 20, so as not to interfere with the movements of this latter, and to allow the pallets 21 to remain resting on said surface, as clearly shown in Figures 4 and 5.

The empty pallet feed device 22 can be constituted by a motorised conveyor belt 61 followed by a number of idle rollers 62, and the full pallet removal device 23 can be constituted by a fixed motorised roller table 63. When the mobile roller table 38 is in its raised position, its rollers 55 are at the same level as the conveyor belt 61 and rollers 62 and 63, so that the pallets 21 can be conveyed on to the trolley 20 in a direction perpendicular to the direction of movement of said trolley. When the roller table 38 is lowered, a pallet 21 located on it is deposited on to the support surface of the trolley 20. Vice versa, when the roller table 38 is raised, a pallet positioned on the trolley 20 can be withdrawn for discharging on to the removal device. It is apparent that the transfer of the pallets 21 on to and from the trolley 20 must take place with the trolley at rest.

In order to halt, in the required position, an empty pallet fed by the feed device 22 and conveyed into the loading station by the rollers 55 of the raised roller table 38, suitable photoelectric cell systems (not shown) can be provided to halt the rollers 55 at the correct moment. The final positioning of said pallet can then be done by reversing the direction of rotation of the rollers 55 to push the pallet against a stop bar made to rise to the rear of the pallet transformed on to the roller table 38. These means are not shown in detail, and can be formed in various different ways.

The operation of the described apparatus is then as follows. A number of empty pallets 21 equal to the number of arrival channels 14-17 for different objects must firstly be positioned on the mobile trolley 20. In the illustrated example, there are four said channels and thus four pallet positions on the trolley 20. In order to deposit an empty pallet on to the trolley 20, this latter is moved along i.s axis (in one of the directions indicated by the double arrow in Figures 1,3 and 4) in order to move the position to be occupied by the pallet into the loading station, the roller table 38 is then raised in order to be able to receive from the feed device 22 an empty pallet, which by means of the moving rollers 55 is conveyed into the required position.Having reached the exact position, with the aid of the aforesaid means, the rollers 55 are halted and the roller table 38 is lowered, to thus deposit the empty pallet on to the trolley 20. This operation is repeated a number of times equal to the number of positions on the trolley 20 to be occupied by pallets.

The actual palletising operation can now begin.

For this, the roller table 38 is lowered to allow the free movement of the trolley 20 in order to move a pallet into the loading station as required, in relation to the arrival channel from which the objects to be stacked layer by layer on said pallet are discharged.

The pal lets are loaded, as stated, layer by layer according to the availability of objects in the arrival channels. Suitable automatic controls are included which, sensing the availability of objects in the various arrival channels, provide for moving the trolley 20 in order to place the required pallet into the loading station, and for opening the relative channel.

As soon as a pallet has been loaded with the required number of layers of objects, the trolley 20 is halted with this full pallet in the loading station.

The roller table 38 is then raised for the purpose of withdrawing the full pallet from the trolley 20, and its rollers 55 are then driven in order to convey this full pallet on to the removal device 23. The rollers 63 of this latter device are also moving, and thus the full pallet is removed.

Simultaneously, and with the roller table 38 still raised and the rollers 55 moving, the empty pallet feeder 22 is operated in order to replace the removed full pallet with an empty pallet.

The advantages of the apparatus according to the invention are apparent from the aforegoing description.

The pallet support trolley is structurally simplified to a maximum extent, being constituted by a simple slidable frame comprising a direct upper support surface for the pallets, without any mobile member mounted on it. At the same time, the system for positioning the empty pallets on the trolley and for removing the full pallets is made very simple. This is attained by providing in the loading station a single motorised roller table which can be raised in order to withdraw and convey the pallets, and lowered in order to allow free transverse movement of the pallet support trolley without any interference.

Claims (6)

1. An apparatus for palletising, layer by layer on relative pallets, objects of various kinds originating from separate channels, comprising a single device for forming individual layers of objects and containing a pallet loading station, a trolley carrying a number of pallets at least equal to the number of kinds of objects and mobile in order to move a pallet into the loading station when required, a conveyor connecting the object arrival channels to the layer forming device in order to feed this latter as required with objects originating from one of the channels in the required number for forming a layer, an empty pallet feed device and a full pallet removal device, and a synchronised automatic control system for operating the various members and devices, characterised in that said mobile trolley is constituted by a frame with longitudinal members and connecting cross-members, the longitudinal members forming the pallet support surface, there being disposed in the loading station of the device for forming individual layers of objects a motorised roller table which can be moved from a raised position in which it creates continuity between the empty pallet feeder and the full pallet removal device, these being disposed in-line, to a lowered position below said pallet support surface of the pallet support trolley.

2. An apparatus as claimed in claim 1, characterised in that the longitudinal members of the pallet support trolley slidably rest on idle guide rollers, drive means being provided to move the trolley on these guide rollers.

3. An apparatus as claimed in claim 2, characterised in that said drive means comprise a fixed motorLaperating pinions which engage with racks rigid with said longitudinal members, said motor being reversible.

4. An apparatus as claimed in claim 1, eharacterised in that the roller table comprises a framework in which a plurality of rollers with parallel axes are rotatably supported, said framework carrying drive means arranged to rotate said rollers.

5. An apparatus as claimed in claim 4, characterised in that said framework rests on rollers carried by support arms, there being provided means for angularly moving said support arms and means for vertically guiding the framework.

6. An apparatus for palletising, layer by layer on relative pallets, objects of various kinds originating from separate channels, substantially as hereinbefore described with reference to the accompanying drawings.