GB2101068A - Can handling apparatus - Google Patents

Abstract

Apparatus for handling cans, particularly in the food-processing industry, includes a conveyor comprising lane members forming channels (21) in which the cans slide under the action of pins (23) carried by circulatory impeller chains projecting into the channels (21), flexible deflecting elements (33) carried by gantries (31) being mounted over the channels (21) to engage cans in the channels, so that a can which is propelled along a channel (21) in one orientation by means of a particular pin (23) may be engaged by a deflecting member so as to turn the can around the said pin (23) into a different desired orientation. <IMAGE>

Description

SPECIFICATION Can handling apparatus The present invention relates to can handling apparatus. More particularly the invention relates to can handling apparatus known as "unscramblers". Unscramblers are necessary in can handling operations where cans come from a bulk operation such as sealing, cooking or sterilizing, and where they are progressing to an operation which is performed on each can singly or on a specified number of cans at one time e.g. labelling or packing.

Unscramblers transform a jumbled mass of cans (scrambled cans) into a line or lines of cans all having the same orientation (unscrambled cans).

A number of forms of unscrambler are known. One example is an unscrambler sold by Dudley Machinery Company of California, U.S.A. This unscrambler consists of a number of parallel conveyor belts tilted laterally. At the lower side of each tilted belt is a stationary rail which cans may slide against. Fixed to each rail is a number of checks such as springs or studs. Each check prevents a can with a particular undesired orientation from passing until the can changes its orientation as a result of the movement of the belt combined with the friction effect of the check.

It is a requirement with this unscrambler that all possible orientations of a can must be such as to be distinguishable by the apparatus, so as to determine whether re-orientation of any particular can is required or not. Thus with "tall"cans, i.e. cans in which the height to diameter ratio is substantially greater than one, it is relatively easy for the machine to distinguish between the different possible orientations of the cans. However, the ability to distinguish the different orientations becomes a greater problem with "squat" cans (i.e.

cans in which the ratio is approximately equal to one). "Flat" cans (i.e. the ratio is less than one) are usually unscrambled by apparatus designed specifically for handling such cans.

Another example of an unscrambler is that sold by Fox Brothers Manufacturing Inc. of Ohio, U.S.A., which comprises a rotating auger side by side with a conveyor belt. The auger orientates a can by placing it in an upright position. Mechanical checks which are provided at the end of the auger cause a can to be returned to the start of the unscrambler, if the can is not in the desired orientation.

In a number of other machines, parallel conveyor belts are employed which are separated from one another by narrow rubber conveyor rails which move faster than the belts. The narrow rubber rails are provided with projections which orientate the cans on the conveyor belts. One example of such a machine is sold by The Shuttleworth Company of Indiana, U.S.A.

Many of the above-mentioned machines utilize at some stage in the unscrambling process, features which can damage cans. Present day cans are made from very light gauge material which results in cans being very susceptible to damage. The types of damage that may occur to cans include denting which takes from the overall appearance of the can, and damage to the seam of the can, which affects the hermetic sealing of the can.

Squat cans are regarded as being the most difficult sized cans to unscramble. Hitherto, the unscrambling of squat cans has generally required the constant attention of an operator to keep the unscrambling process flowing smoothly.

It is a general object of the present invention to provide can-handling apparatus which will enable cans to be unscrambled in a more effective manner than has been possible with apparatus in use hitherto.

A more specific object of the invention is to provide can-handling apparatus which will enable cans to be unscrambled with a reduced risk of can damage as compared with apparatus in use hitherto, which will be readily adaptable for the handling of cans over a wide range of can sizes, and which will require the minimum of supervision by an operator.

In can-handling operations in the food industry, hygiene is of very great importance. It is therefore a further object of the invention, to provide can-handling apparatus which can readily be constructed in such a way that it will be easy to clean and will not possess any structural features which will form a trap for bacteria.

One form of apparatus for orientating empty cans, before they are delivered to a can-filling machine, is disclosed in U.S. Patent Specification No. 2937738 (Albertoli). In the apparatus disclosed, the empty cans are delivered to a steeply inclined belt conveyor. Magnetic means are provided to retain the cans in contact with the belt, so that they are enabled to move up the steep slope of the belt conveyor.

U.S. Patent Specification No. 3690437 (Kammann) discloses apparatus which is primarily intended for handling bottles, and which includes a device which engages the necks of the individual bottles and brings them into an erect position. In order to feed the bottles to the erecting device, they are entrained by a conveyor having driver elements which engage the bottles and propel them along a plurality of channels, towards the erecting device.

According to the present invention, apparatus for handling cans includes at least one conveyor comprising a plurality of channels or lanes, adapted to receive cans in sliding engagement therein, and a circulatory impeller element having projecting members such as pins thereon, projecting into the channels to engage cans supplied to the input end of the conveyor and to propel them along the channels, and means to engage cans as they are propelled along the channels to turn them into desired orientations, whereby cans supplied to the conveyor in a random fashion are discharged at the output end of the conveyor in desired orientations.

The channels or lanes may conveniently be formed by mutually inclined plate members which extend lengthwise of the conveyor and which co-operate to define channels of Vshaped cross-section. Alternatively, the Vshaped channels may be constructed from rod-members of circular or other cross-section.

When cans are fed in random fashion to the input end of a conveyor as referred to above, individual cans are engaged by the projecting members, so that the cans are fed along the channels in single file. Some cans taken into the channels will be found already to be in the desired orientation. For example, some "tall" cans will be orientated with their longitudinal axes aligned in the direction of movement of the cans along the conveyor. Other cans will have their orientations altered during movement along the conveyor, by the effect of friction, as the cans slide relatively to the surface of the members defining the channels.

This effect may be enchanced by arranging the conveyor to be inclined upwardly from its input end to its output end. In that event, deflecting means for engaging the cans may advantageously be mounted at the elevated output end of the conveyor, to turn the cans into the desired orientation.

The invention will now be described more particularly, by way of example only, with reference to the accompanying drawings. In the drawings: Figure 1 is a side elevation of the apparatus of the invention; Figures 2, 3 and 4 are sectional views on the lines Il-Il, Ill-Ill and IV-IV of Fig. 1, all drawn to a larger scale; Figure 5 is a fragmentary view from the righthand end of Fig. 1,showing a detachable final section of the apparatus, which can be fitted when required; Figure 6 is a view from the same viewpoint as Fig. 5, but showing tripper members which can be fitted to the final section of the apparatus; Figure 7 shows one of the tripper members of Fig. 6, drawn to a larger scale.

Fig. 1 shows a feed conveyor 1 (not part of the apparatus of the invention) which feeds cans in a jumbled mass from a sterilizing unit (not shown) to the unscrambling apparatus of the invention. The apparatus of the invention comprises a primary conveyor 2 which carries out a first unscrambling stage in which the cans are divided into lanes and a secondary conveyor 3 which completes the orientation and aligning of the cans in the lanes. Feed conveyor 1 and the front end of primary conveyor 2 are immersed in a water-tank or canal 4. Feed conveyor 1 is arranged to deliver the cans to primary conveyor 2, preferably in a layer one can deep. Conveyors 2 and 3 are driven at different speeds. Drive motor 7 directly driven secondary conveyor 3 by a chain drive 8. Primary conveyor 2 is in turn driven from secondary conveyor 3 through a reduction sprocket chain drive 8a.A plate 9 forms a chute to guide cans under water, from feed conveyor I to primary conveyor 2.

Referring to Figs. 2 and 3, it will be seen that the conveyors 2 and 3 comprise four separate parallel guide lanes or channels 21, along which cans may be moved. The lanes are formed from two elongate side members 24 and three elongate inverted V-shaped intermediate members 24a. Lane members 24 and 24a are supported by lane support gantries 26 from which lane members 24 and 24a are suspended by rods 25. The lane members 24 and 24a are juxtaposed to form four slots 27 extending throughout the length of the apparatus. The gantries 26 and other components of the apparatus are supported by underframes 5 and 6.

Each of the members 24 and 24a extends over the whole length of the apparatus. The side members 24 and intermediate members 24a are of the same shape when viewed in side elevation, this shape being best seen in Fig. 1 wherein one of the side members 24 is clearly visible. The member 24 is mounted so as to have a rising section 1 2 associated with conveyor 2 and rising to a high-point 14. This is followed by a descending section 10, a rising section 1 3 associated with conveyor 3 and a final descending section 11.

Protruding through each slot 27 defined by the members 24,24a and into each lane 21 are evenly spaced pins 23. As can be seen in Figs 2 and 3, the pins are arranged in rows of four, the pins of each row being carried by a mounting member 28 which may conveniently be a square section tube. Each end of each tube 28 is fitted to an endless chain 29 which is driven by chain drive 8 or 8a. As mentioned above, in the construction shown in the drawings, the members 24 and 24a are suspended from overhead by means of the gantries 26. The distance that pins 23 protrude into lanes 21 may be varied by changing the height of gantries 26 by means of wing nuts 22.

Instead of the members 24,24a being adjustably suspended from overhead as illustrated, they could be fixedly mounted from underneath, enabling ther gantries 26 to be dispensed with. However, it would then be necessary for the chains 29 to be mounted so as to be adjustable up-and-down, so as to vary the amount by which the pins 23 protrude through the slots 27.

As cans are fed from feed conveyor 1 to conveyor 2, they are entrained by the pins 23. The plate 9 is a flat sheet of metal shaped to interengage or mesh with the lanes 21 of conveyor 2. Slots are formed in the sheet to allow the pins 23 to pass unhindered. The chief function of the plate 9 is to guide cans discharged from feed conveyor 1 into engagement with conveyor 2 and to prevent them falling down into water-tank 4.

Cans fed to the lanes 21 of conveyor 2 are caused by the pins 23 to slide upwards along the lanes towards high-point 14. Members 24,24a forming the lanes 21 are shaped so that there is a smooth transition from conveyor 2 to descending section 10, from section 10 to conveyor 3 and from conveyor 3 to final descending section 11.

Further gantries 31,32 are mounted at positions corresponding to the high-points 14, 15; these gantries are shown broken away in Fig.

1, so as not to obscure other features. However, the details of gantry 31 are clearly shown in Fig. 3 and gantry 32 is of similar construction.

Each gantry 31,32 carries eight flexible members constituted by coil springs 33 which depend from the gantry, two such springs being associated with each lane 21. The height of gantries 31,32 above the lanes 21 may be adjusted by means of wings nuts 39.

In addition, the wing nuts allow limited adjustment of the positions of the gantries 31, 32 backwards and forwards relatively to the high-points 14,15. Each spring 33 is mounted on the gantry 31 by means of a threaded shank 34 engaged in an elongated hole (not visible in the drawings) in the gantry. The shank 34 is secured in position by nuts 35 by means of which the height of the spring 33 relatively to the gantry can be adjusted. Also, when the nuts 35 are slackened, the elongated mounting hole enables the position of the shank 34 and spring 33 to be adjusted from side-to-side as viewed in Fig.

3, so as to adjust the positon of the spring 33 laterally relatively to the associated lane 21.

Two additional gantries 38 are provided in association with secondary conveyor 3.

Mounted on each gantry 38 are four spring checks 37. As can be seen in Fig 4, the spring checks 37 are similar to the springs 33 of Fig. 3, but the gantries 38 each have only one spring check 37 associated witb each lane 21, and the spring checks 37 are mounted obliquely as shown in Fig. 4. The spring checks of the respective gantries 38 are oppositely inclined relatively to one another. The function of the springs carried by the gantries 31, 32 and 38 will be described hereinafter.

When cans have passed throughout the length of the apparatus as shown in Fig. 1, they are discharged from the final section 11.

As shown in Fig. 1, section 11 is constituted by a continuation of the lane members 24, 24a. In some circumstances it is necessary to provide a modified form of final section which when required, can be inserted in engagement with final section 11, at the position indicated by the dotted line 1 1a. The use of this modified form of final section is required, in particular, when the machine is being used for handling "squat" cans. When the machine is used for handling "tall" cans, the standard final section 11 is used.

The unscrambling operation for squat cans will now be described.

Cans from the sterilizing unit are fed in a jumbled fashion from feed conveyor 1 to primary conveyor 2. The transfer from conveyor 1 to conveyor 2 takes place in water, thus cushioning the cans against impact. Due to the V-shaped construction of lanes 21, the cans take up positions in one of the four lanes of primary conveyor 2. The cans then advance in four lines up primary conveyor 2 under the action of the pins 23. The pins 23 of conveyor 2 must be longer than the pins 23 of conveyor 3 due to the necessity to propel the cans through the water and into the air, and the probability that more than one can may be in front of each pin.

The cans are advanced up primary conveyor 2 towards the high-point 14. Some of the cans will already be correctly orientated at this stage and they simply pass continuously through the apparatus. The desired orientation for squat cans is for the base of each can to sit on one or other of the two sides of a Vshaped lane 21. The undesired orientation is for the base of a squat can to straddle the two sides of a V-shaped lane 21, with the axis of the can lying parallel to the longitudinal axis of lane 21. A can in the undesired orientation has a greater surface contact between the can and the lane members defining the lane 21 in which it is engaged, and therefore a good deal of friction is generated between the can and lane 21. If slightly more friction occurs at one side of the lane than the other, then the can will turn slightly.This slight turn will sometimes be sufficient for pin 23 to change the orientation of the can to the desired orientation. However, if a can in the undesired orientation reaches the highpoint 1 4 without being correctly orientated, it will have a higher vertical profile than a can in the desired orientation. The springs 33 carried by gantry 31 can be set to prevent a can in the undesired orientation from passing while allowing a can in the desired orientation to pass. When a wrongly orientated can contacts a spring 33, the spring turns the can and flips it back over the pin 23 which is pushing the can. The can then comes to rest in front of the following pin or if another can is in front of that pin, displaces that can to another pin.

Thus it will be seen that the height of pins 23 projecting into lanes 21 is crucial. The pins must be high enough to propel the cans but low enough to allow cans to go over them, if the cans are obstructed.

As the cans propelled by the pins 23 of conveyor 2 reach the high-point 14, they roll gently down section 10 and are entrained by the pins 23 of conveyor 3. The arrangement of the springs 33 carried by gantry 31 at the high-point 14, where the pins 23 of conveyor 2 reach the end of the upper run of conveyor 2 and commence their return movement has been found to be particularly effective in ensuring that wrongly orientated cans are flipped over into the desired orientation. However, any cans which pass the high-point 1 4 while still being incorrectly orientated, will be dealt with by the springs carried by the gantries 38 and 32 associated with conveyor 2.

Secondary conveyor 3 travels faster than primary conveyor 2, thus serving to space out the cans coming from section 10.

After passing the high-point 1 5 of conveyor 3, the cans will be correctly orientated in lanes 21, with the base of each can sitting on one of the two sides of the V-shaped lane 21.

As previously mentioned, when handling squat cans, a modified final section is inserted in position, where indicated by the dotted line 11 a. This consists of four trough-elements as shown in Fig. 5, each forming a continuation of one of the lanes 21.

Fig. 5 is a view taken from the right-hand end of Fig. 1, showing the modified final section 1 lea in position. This modified final section is made by bending a single sheet of metal into the shape shown in Fig. 5, so as to form the four trough-elements 51. The trough-elements 51 are V-shaped at one end, so as to correspond in shape with the lanes 21 formed by the lane members 24,24a.

Thus each trough-element 51 forms a smooth continuation of the corresponding lane 21.

Each trough-element 51, is then outwardly flared so as to form a trough with a flat bottom 52 and slightly inclined side walls 53, 54.

As a squat can passes the high-point 1 5 of secondary conveyor 3, it rolls down the corresponding lane 21, with its cylindrical surface in rolling contact with one or other face of the lane 21. As the can enters the flared portion of the corresponding trough-element 51, it slides into a position in which its cylindrical surface contacts the flat bottom 52; it then rolls down the latter and is discharged.

The unscrambling of tall cans will now be described. With tall cans the desired and undesired orientations of the cans are reversed as compared with the desired and undesired orientations of squat cans. Tall cans are in a more stable orientation when the base of the can is straddling the two sides of V-shaped lane 21, i.e. with the axis of the can lying parallel to the longitudinal axis of lane 21. The orientation of tall cans may be corrected in any of three ways: (1) Tall cans in the undesired (upright) orientation are unstable and will tend to fall over into the desired orientation.

(2) In transferring from primary conveyor 2 to secondary conveyor 3, tall cans tend to slide "head first" down section 10 and thus assume the desired orientation.

(3) The springs 33 positioned at highpoints 1 4 and 1 5 flip over cans which are in the undesired orientation.

The cans are discharged from the unscrambler by means of the final descending section 11.

It may sometimes occur, that if two tall cans are iocated between two successive pins 23, one of which is in the correct alignment in the corresponding channel 21, this can may prevent the second can being flipped over into the correct alignment. In order to safeguard against this possibility, as shown in Fig. 6, tripper members 61 may be provided in the channels 21 of final section 11. One tripper member 61 is shown in detail in Fig.

7. It will be seen that tripper 61 is secured in channel 21 by a threaded shank 62 and a nut 63, so that the position of the tripper may be adjusted. Tripper 61 has a curved surface 64, so that it allows a can which is in the correct orientation to pass unimpeded. However, when a can which is in the incorrect (upright) position encounters the tripper 61, the can is caused to topple over into the correct alignment in channel 21.

Similar tripper members may also be provided in association with the intermediate descending section 10.

The can-unscrambling machine in accordance with the invention can readily be constructed so as to have a larger number of lanes than is the case with some of the known unscrambling machines mentioned at the outset. For this reason, the machine can be operated at a lower handling speed in each lane than the known machines, without reducing the overall output as compared with known machines. The relatively low can-handling speed helps to ensure gentle handling of the cans.

Economic operation of the machine described above can be achieved with an output for each lane of from 50 to 100 cans per minute, which compares with 1 50 cans per minute per lane in certain known unscramblers.

Thus with an output of up to 100 cans per minute per lane, the four-laned apparatus described can handle up to 400 cans per minute. To achieve a greater throughput, the apparatus may be constructed with a greater number of lanes. In the apparatus described, the lanes are relatively narrow as compared with previously known unscramblers. Thus for a given overall width of apparatus, substantially more lanes can be accommodated than hitherto, enabling a slower can-speed to be adopted.

Only simple adjustments are necessary to handle different can-sizes up to a maximum can-diameter. In order to handle cans with a diameter greater than this maximum, the existing lane members are replaced by members providing larger sized V-shaped channels.

The deflecting means provided for engaging the cans and reorientating them have been described above as being constituted by coil springs. However, any other suitable form of flexible deflecting elements may be employed, such as for instance, fingers of rubber or like resilient material.

To aid in the gentle handling of the cans, the pins may be provided with a plastic or rubber coating. While the initial feeding of the cans in water as described, aids in the gentle handling of the cans, the initial feeding can quite safely take place in air.

It will be seen that the general open construction of the apparatus aids in maintaining the apparatus clean and free of build-up of bacteria.

It is to be understood that the invention is not limited to the specific embodiment described herein, which is given by way of example only, and that various modifications and alterations are possible within the scope of the invention as defined by the claims.

Claims (14)

1. Apparatus for handling cans or like containers, including at least one conveyor comprising a plurality of stationary channels to receive containers in sliding engagement therein, a circulatory impeller element having projecting members projecting into the channels to engage containers supplied to the conveyor, to propel them along the channels, and flexible deflecting elements mounted over the channels to engage containers moved along the channels by the projecting members, such that a container which is propelled along one of channels in one orientation by means of one of the said projecting members, may be engaged by one of the said deflecting elements so as to pivot the container about the said one projecting member, into a different desired orientation.

2. Apparatus according to claim 1, wherein at least one gantry is mounted above the said channels and wherein the deflecting members depend from the gantry.

3. Apparatus according to claim 1 or claim 2, wherein the deflecting members comprise spring members.

4. Apparatus according to claim 1, which includes primary and secondary conveyors, each having a circulatory impeller element, and wherein the channels are defined by lanemembers which extend throughout the apparatus while the circulatory impeller elements of the primary and secondary conveyors each extend over a part of the length of the channels.

5. Apparatus according to claim 4, wherein the primary conveyor is mounted to inclined, so as to discharge containers at a position which is raised relatively to the secondary conveyor, and wherein the lane-members defining the channels are shaped to guide containers in downward sliding movement from the said raised position of the primary conveyor to the secondary conveyor.

6. Apparatus according to claim 4 or claim 5, including means for driving the two circulatory impeller elements at different speeds.

7. Apparatus according to claim 5, wherein the secondary conveyor is mounted to be inclined, so as to propel containers upwardly towards a raised position.

8. Apparatus according to claim 4, wherein flexible deflecting elements are mounted to engage containers conveyed by the primary conveyor, at the said raised position thereof.

9. Apparatus according to claim 7, wherein flexible deflecting elements are mounted to engage containers conveyed by the secondary conveyor, at the said raised position thereof.

1 0. Apparatus according to claim 8 or claim 9, wherein the said deflecting elements at the said raised position of the primary or secondary conveyor are mounted in a row comprising a pair of laterally spaced elements associated with each channel of the said primary or secondary conveyor.

11. Apparatus according to claim 9, wherein flexible deflecting elements are also provided at at least one intermediate position of the secondary conveyor.

1 2. Apparatus according to claim 11, wherein the deflecting elements provided at the said intermediate position of the secondary conveyor comprise a deflecting element associated with each channel of the secondary conveyor and extending obliquely relatively to the width of the channel.

1 3. Apparatus according to claim 7, including a chute-member extending from the said raised position of the secondary conveyor, to discharge containers from the secondary conveyor.

14. Apparatus according to claim 13, including tripper members associated with the said chute-member.

1 5. Apparatus for handling cans or like containers, substantially as herein described with reference to and as shown in the accompanying drawings.