GB2061856A

GB2061856A - Apparatus and method for combining articles delivered in rows into a single output file

Info

Publication number: GB2061856A
Application number: GB8030232A
Authority: GB
Original assignee: Metal Box PLC
Current assignee: Crown Packaging UK Ltd
Priority date: 1979-10-30
Filing date: 1980-09-18
Publication date: 1981-05-20
Also published as: DK266781A; WO1981001281A1; EP0038812A1; JPS56501399A

Abstract

An apparatus for combining articles delivered in successive rows into a single output file, includes a horizontal circulation table (20) having a plurality of nozzles (30) for the escape of air from a pressure chamber beneath as air jets inclined upwardly at a small angle. These jets are oriented in different directions in different zones (22, 24, 26, 28) of the table (20), so that an article (e.g. an empty can) is carried by the air jets in the respective directions indicated by the arrows. Articles delivered on an inlet conveyor (12) are received from the table by an outlet conveyor (14) moving at higher speed. Zone (28) constitutes a straight-through zone for delivery of one file of incoming articles directly to the outlet conveyor. Articles of the other incoming files move on to zone (26) for merging as opportunity arises with articles moving away, spaced apart, on zone (28). Those articles which cannot merge in the output file are pushed on to zone (22) where they are redirected to zone (24) and then to zone (26), for subsequent merging with the said output file.

Description

SPECIFICATION Apparatus and method for combining articles delivered in rows into a single output file TECHNICAL FIELD This invention relates to an apparatus and a method for combining articles delivered in successive rows at an inlet position into a single output file of such articles. Such an apparatus (referred to hereafter for the sake of simplicity as a "combiner") and method find application particularly in the metal-can manufacturing industry, though other applications for such apparatus and method will be found in other fields of activity.

In the said can making industry, there is a need for a combiner that will operate consistently and reliably at a deliverly rate of 1000 or more cans per minute without impairing the quality of the cans. Moreover, such a combiner must not be unduly expensive, and should be as compact as possible.

BACKGROUND ART Amongst the combiners which are already known to the can manufacturing industry is one which employs a "waterfall". In this combiner, successive rows of cans conveyed upright along a substantially horizontal conveyor are tipped off the conveyor at its downstream end so that they fall with their axes generally horizontal (this can-discharge arrangement is known as a "waterfall" in the art). A second horizontal conveyor travelling at right angles to the first is arranged to receive the cans on their sides so that each row of cans on the first conveyor becomes a single file of cans on the second. In order to direct the cans on to the second conveyor, two vertical guide plates are positioned below the downstream end of the first conveyor and the second lies between these plates.When this combiner is operating at the high speeds mentioned above, there is a tendency for the cans to be flung against the guide plates and to fall on top of one another on the second conveyor, and as a result the efficiency of the combiner and also the quality of the cans themselves may be impaired.

In a modified form of such a combiner, the guide plates are replaced by two vertically extending air cushions which serve to guide the cans as they fall. A plurality of air jets provide the cushions, and the jets are directed so that the cans do not fall directly from the first conveyor onto the second but rather are circulated vertically during their passage between the two conveyors. By appropriate adjustment of the air flows the rate at which the cans fall onto the second conveyor may be varied (in contrast to the arrangement incorporating the said guide plates) to obtain efficient operation of the combiner and to minimise damage to the cans.Nonetheless, the performance of this arrangement may deteriorate at high throughputs of 1000 or more cans per minute, when the quantity of cans discharged from the first conveyor exceeds the number that the air jets flow can satisfactorily control.

One such modified form of combiner is disclosed in the US Patent Specification 4,182,586.

DISCLOSURE OF THE INVENTION The present invention seeks to provide a combiner, and a method of combining articles, which meets the afore-mentioned requirements.

According to the present invention there is provided an apparatus for combining articles delivered to an inlet position in a succession of rows into a single file of such articles for delivery at an outlet position, which apparatus includes a circulation table for receiving said articles from said inlet position via an inlet passageway, and for delivering them to said outlet position via an outlet passageway, said table having propelling means for propelling said articles received and carried on said table around at least a part of a closed circulation path towards said outlet passageway for delivery thereto, said outlet passageway communicating with said table in a direction that is substantially tangential to said circulation path, and said propelling means being arranged at successive sections of said table to propel each such article in progressively different directions around said circulation path whereby an article (hereafter referred to as a by-pass article) that has by-passed the entrance to said outlet passageway circulates around said circulation path towards and traverses the mouth of the said inlet passageway so that it is delivered in the direction of circulation to said outlet passageway.

With such an arrangement, said articles are at all times mechanically and well supported by said table and associated passageways, so that there is less risk, as compared with the said prior art combiners, of said articles suffering damage.

Furthermore, as compared with the prior art combiners using vertical circulation, combiners according to the present invention require less head-room.

Preferably, said inlet passageway communicates with said table in a direction that is substantially tangential to said circulation path whereby articles delivered through said inlet passageway carry with them, in the direction of circulation, any such by-pass articles then seeking to traverse the mouth of the said inlet passageway; and said inlet and outlet passageways are aligned with one another, and project from a peripheral part of said table in opposite senses.

Advantageously, a first said section (referred to hereafter as said first section) has its propelling means arranged to propel articles in single file from a part of said inlet passageway directly to said outlet passageway.

Said circulation table may have N said sections, N being an integer greater than two, and said directions of propelling said articles in successive sections differing progressively by successive increments of 360/N degrees.

The width of a said section transverse to the direction of propelling articles on said section is preferably less than that of the preceding section, at least around a part of said circulation path.

Said outlet passageway is conveniently provided with propelling means for propelling articles delivered to its entrance from said circulation path in a direction away from said table and towards said outlet position.

Guide means may be provided externally of said circulation path whereby to prevent articles travelling around said path in their normal travelling-attitude leaving said circulation path at its external boundary except through said outlet passageway. Likewise, other guide means may be provided internally of said circulation path to prevent such articles leaving that path at its internal boundary. The first-mentioned guide means may be provided with an article-escape aperture through which articles not travelling in said attitude may escape from the circulation path or otherwise be retrieved.

According to another preferred feature of the present invention the or each said propelling means comprises a fluid (preferably-air) propelling means for creating when in operatin on the or each respective said section of bed of fluid travelling in the said direction of movement of said articles on that section.

Such a propelling means may conveniently comprise a fluid jet propelling means constituted by a plurality of apertures formed in said section of said circulation table and oriented so as when supplied with fluid under pressure from the underside of said table to provide a plurality of fluid jets for propelling articles on said section in said direction along said section. Where said circulation table is formed of sheet material, said apertures may be formed by cutting free and depressing flaps of said sheet material.

According to a second aspect of the present invention there is provided a method of combining articles being delivered to an inlet position in a succession of input rows into a single output file of such articles for delivery to an output position, which method comprises -propelling along a peripheral part of a closed circulation path directly to said outlet position a single file of said articles being delivered to said inlet position, and -propelling other articles (hereafter referred to as "by-pass articles") in other files of said articles being delivered to said inlet position around said circulation path and returning such by-pass articles across the paths of other articles being delivered later in said other files, for delivery as opportunity arises to said peripheral part of said circulation path for merging there with articles being propelled in said single file directly to said outlet position.

Other features and advantages of the present invention will appear from the description that follows hereafter, and from the claims that are appended at the end of that description.

One combiner according to the present invention, for combining thin-walled metal cans, will now be described by way of example and with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a plan view of the combiner with its cover Figure 2 is a perspective view of the combiner with parts broken away; Figure 3 is a fragmentary section through a circulation table plate of the combiner; and Figures 4 and 5 show plan views of alternative forms of circulation table incorporated in modified forms of said combiner.

Referring now to Fig. 1, an air-operated combiner 10 is disposed between wider, input belt conveyor 1 2 and a narrower, output belt conveyor 1 4 arranged respectively upstream and downstream of the combiner 1 0. Dead or junction plates 16, 1 8 link the combiner to the upstream and downstream conveyors 1 2 and 14 respectively. These junction plates 16, 18 constitute inlet and outlet passageways respectively of the combiner.

The combiner 1 9 itself comprises a horizontal metal plate 20 which constitutes a cancirculation table. The plate 20 is divided as shown in Fig. 1 into four generally-rectangular zones 22, 24, 26 and 28, and each such zone is provided with a plurality of openings 30 (see Fig. 3) formed by releasing (cutting) and downwardly inclining a plurality of rectan- gular flaps 32 from the plate 20. Such flaps are bent downwardly about what are referred to herein as their "leading edges" 34. The openings 30 enable jets of compressed air from an air reservoir below the plate to be directed over the upper surface of the plate 20, the direction of each such jet being in plan view perpendicular to the leading edge 34 of the flap 32 over which the jet travels from the reservoir.

All the jets in any one of said zones are directed in the same direction, and in each zone this direction is indicated by an arrow.

As can be seen from Fig. 1, the respective zones have their openings 30 arranged so that the jets in the respective zones are directed generally around a closed circulation path which proceeds from a first zone 28 through the successive zones 22, 24 and 26. The first zone 28 is aligned with the input and output conveyors 1 2 and 14 and has its respective ends adjoining the junction plates 1 6 and 1 8 respectively. In the case of each of the zones 22, 24 and 26, the jets thereof are directed towards the next downstream zone (i.e. 24, 26, 28 respectively) which lies immediately adjacent thereto and in which the jets are directed in a perpendicular direction thereto.

Furthermore, defining the "width" of each zone to be its dimension transverse to the direction of its jets, it will be seen that the widths of the zones 22 to 28 decrease progressively.

Turning now to Fig. 2, an air reservoir chamber 36 for receiving air under pressure from a source (not shown) is provided below the plate 20 and communicates with the jet openings 30. Above the plate 20 a lateral guide 38 bounds the closed circulation path provided by the zones 22 to 28. The guide 38 is smoothly curved at the corners of the zones 22, 24 and 26, and has a horizontallyextending opening 40 provided for reasons that will be described later. A cover plate 42 is adjustably mounted above the circulation table and guide 38 and contains vent holes 44.

Operation of the described apparatus for combining input rows of cans into a single output file is as follows:- Firstly, the cover plate 42 is adjusted in height so that the distance between this and the plate 20 is marginally greater than the height of the cans to be received by the combiner from the input conveyor 1 2.

The speeds of the two conveyors 12, 1 4 are set so that the output conveyor 1 4 travels six times as fast as the input conveyor 12, and successive rows of cans, each containing six upright cans disposed base-downwards, are supplied to the conveyor 1 2. It should be noted that if instead the rows on the input conveyor 1 2 each contain 'n' cans, the output conveyor 1 4 would be arranged to travel at a speed which is 'n' times as fast as that of the input conveyor 12.

As the rows of cans reach the combiner 10 they 'float' onto the bed of air provided by the jets issuing through the openings 30. Some of the cans (i.e. those in the file of input cans that are aligned with the zone 28) pass directly onto the "straight-through" zone 28, the width of that zone corresponding approximately to the diameter of a can, and, propelled by the jets in that zone, this file of cans passes directly on to the output conveyor 1 4.

Other cans arriving in the other files on the input conveyor travel onto the zone 26 where they are urged across the mouth of the inlet passageway (constituted by the junction plate 1 6) towards the zone 28. Those cans which cannot find a place in the zone 28 between cans already passing therealong are urged sideways in the zone 26 either by engagement with the cans in the zone 28, or by other cans arriving on the input conveyor 12, until they reach the zone 22. Once here, they are circulated around the closed circulation path by the action of the jets issuing from the table in the respective zones 24 and 26 towards the zone 28 again, where they mingle with cans travelling in that zone or are swept aside to the zone 22 for recirculation around the table.

During the circulation of the cans in the combiner, the guide 38 acts to prevent the outermost cans from leaving the circulation table. Any cans which inadvertently arrive on their sides, instead of the closed ends, are ejected from the table through the opening 40, and hence cannot create a blockage within the combiner. Once in the combiner, the cans are prevented from falling over by the closely-adjoining cover plate 42.

Although the described operation concerns upright cans standing on their bases, it is thought that the combiner would work equally well with cans base upwards.

In a modified form of the combiner described above, the circulation table 20 is extended as shown in the Fig. 4 to include as an integral part thereof a long outlet passageway 1 8 which is intended to deliver cans directly at an outlet position, without the use of a separate conveyor such as 14. That outlet passageway is provided with apertures similar to the table apertures 30 for enabling jets of air to issue from an air reservoir below and propel cans along that passageway directly to said outlet position.

It will be observed that in Fig. 4 the circulation table is fed with cans directly at its inlet position by the inlet conveyor 12, without the use of a junction plate 1 6. In this case, said inlet passageway is constituted by the mere inlet opening to the table.

Whereas the combiners described above with reference to the drawings have only four zones or sections on the circulation table, other combiners may use any other number of such zones greater than two. Where a large number of zones is used it may be convenient to make the circulation table circular instead of polygonal. Furthermore, such a circulation table may be made generally annular in form, inner boundary guides as well as outer boundary guides then being provided so as to constrain the cans against movement off the circulation path.

Though it is convenient to arrange said outlet passageway in line with a part of said inlet passageway in the manner shown so that one file of the incoming cans may pass directly to the outlet passageway without change of direction, the outlet passageway may be placed in any other convenient position around the table provided that it has a similar tangential relationship with the table and circulation path thereon, so that one file of cans may pass directly around a peripheral part of said circulation path to said outlet passageway.

The speeds of the air jets in the respective zones may be made constant, or otherwise variable to suit the rate at which cans are being delivered to the circulation table. In general, the air jet speeds should be such as to give a can circulation speed intermediate the respective speeds of the incoming and outgoing cans.

If desired, the speeds of the air jets may be made different in the respective zones of the table; for example the jet speeds may be arranged to progressively increase around the circulation table, giving the highest speed in the fourth (final) zone 26.

Other forms of combiner may have different forms of aperture 30 for producing the air jets; for example, where the circulation table comprises a plate 20 of substantial thickness, said apertures may be formed by drilling holes at appropriate inclinations therethrough.

Though propulsion of the cans through and around the circulation table is preferably achieved by means of said air jet propulsion means, other forms of propulsion means may be used; for example, by appropriatelymounted and driven rollers or belts.

In yet a further modified form of the air combiner described with reference to Figs. 1 and 2, the circulation table (shown in Fig. 5) is of the same outline plan as that of Fig. 4, but the configuration of air jet zones is generally different. Those zones are delineated in Fig. 5 by chain-dotted lines, and the directions in which the jets of air issue from nozzles formed in the table in those zones are indicated by arrows. The nozzles themselves are not shown.

The nozzles are formed by drilling holes in the circulation table at the desired inclinations and orientations so as to provide, in service, air jets issuing from the table in the desired directions. Using the same references as in the Fig. 1, the straight-through zone is represented by 28, and the three other circulation zones by 22, 24 and 26 respectively.

Outwardly of the zones 22, 24 and 26 are border zones 50 having air jets directed inwardly of the table to assist in confining cans to the circulation area.

Between the circulation zone 22 and the straight-through zone 28 is a single row of air jets disposed in the intermediate area 28', and directed to confining the cans being conveyed along the straight-through zone 28 away from the cans being circulated on zone 22.

The outlet passageway 18 may be found integrally with, or separate from the circulation table 20, as desired.

Claims

1. Apparatus for combining articles delivered to an inlet position in a succession of rows into a single file of such articles for delivery at an outlet position, said apparatus including a circulation table for receiving said articles from said inlet position via an inlet passageway, and for delivering them to said outlet position via an outlet passageway, said table having propelling means for propelling said articles received and carried on said table around at least a part of a closed circulation path towards said outlet passageway for delivery thereto, said outlet passageway communicating with said table in a direction that is substantially tangential to said circulation path, and said propelling means being arranged at successive sections of said table to propel each such article in progressively different directions around said circulation path whereby an article (hereafter referred to as a by-pass article) that has by-passed the entrance to said outlet passageway circulates around said circulation path towards and traverses the mouth of the said inlet passageway so that it is delivered in the direction of circulation to said outlet passageway.

2. Apparatus according to Claim 1, wherein said inlet passageway communicates with said table in a direction that is substantially tangential to said circulation path whereby articles delivered through said inlet passageway carry with them, in the direction of circulation, any such by-pass articles then seeking to traverse the mouth of the said inlet passageway.

3. Apparatus according to Claim 2, wherein said inlet and outlet passageways are aligned with one another, and project from a peripheral part of said table in opposite senses.

4. Apparatus according to Claim 3, wherein a first said section (hereafter referred to as said first section) has its propelling means arranged to propel articles in single file from a part of said inlet passageway directly to said outlet passageway.

5. Apparatus according to any preceding claim, wherein said table has N sections, where N is an integer greater than two, and said directions of propelling said articles in successive sections differ progressively by successive increments of 360/N degrees.

6. Apparatus according to any preceding claim, wherein around at least a part of said circulation path, the width of a said section transverse to the direction of propelling articles on said section is less than that of the preceding upstream section.

7. Apparatus according to any one of the Claims 1 to 4, wherein said table has four said sections, said directions of propelling said articles in successive section differing progressively by successive increments of 90 de grees.

8. Apparatus according to Claim 7 asde- pendent on Claim 4, wherein (a) said first section is aligned with and adjoins at its respective ends a part of said mouth of said inlet passageway and the entrance to said outlet passageway, and has its propelling means arranged to propel articles in single file from said part of said inlet passageway mouth directly to said outlet passageway without change of direction;; (b) another said section (fourth and final one around said circulation path, and referred to hereafter as said fourth section) adjoins respectively on adjacent orthogonal sides thereof a remaining part of said inlet passageway, and a part of said first section that adjoins said inlet passageway, said fourth section having its propelling means arranged to propel articles on that section in a direction towards said first section and normal to the direction of travel of articles moving from said inlet passageway on to the circulation table;; (c) another said section (the second around said circulation path, and referred to hereafter as said second section) adjoins respectively on adjacent orthogonal sides thereof a remaining part of said first section, and a part of said fourth section adjacent said first section, said second section having its propelling means arranged to propel articles on that section in a direction away from said first section and transverse to the direction of propelling articles along said first section; and (d) another said section (the third section around said circulation path and referred to hereafter as said third section) adjoins respectively on adjacent orthogonal sides thereof a remaining part of said fourth section and said second section, said third section having its propelling means arranged to propel articles on that section in a direction towards said fourth section and transverse to the direction of propelling articles along said second section.

9. Apparatus according to Claim 8, wherein each of said third and fourth sections has a width transverse to the direction of propelling said articles on said section, which width is less than that of the preceding section in said circulation path.

10. Apparatus according to any preceding claim, wherein said outlet passageway has propelling means for propelling articles delivered to its entrance from said circulation table in a direction away from said table and towards said outlet position.

11. Apparatus according to any preceding claim, wherein said table is provided externally of said circulation path with outer guide means for preventing articles travelling in their normal travelling-attitude from leaving the circulation path at its external boundary except through said outlet passageway.

1 2. Apparatus according to Claim 11, wherein said guide means is provided with at least one article-escape aperture through which an article not travelling in said attitude may leave the circulation path, or otherwise be retrieved therefrom.

1 3. Apparatus according to Claim 11 or Claim 12, wherein said table is provided with inner guide means for preventing articles travelling in said attitude from leaving the circulation path at an internal boundary.

14. Apparatus according to any preceding claim, wherein the or each said propelling means comprises a fluid propelling means for creating when in operation on the or each respective section a bed of fluid travelling in the said direction of propelling articles on that section.

1 5. Apparatus according to any preceding claim, wherein the or each said propelling means comprises a fluid jet propelling means constituted by a plurality of apertures formed in said section of said circulation table and oriented so as when supplied with fluid under pressure from the underside of said circulation table section to provide a plurality of fluid jets for propelling articles on said section in said direction along said section.

16. Apparatus according to Claim 14 or Claim 15, wherein said circulation table is formed of sheet material, and wherein said apertures are formed by cutting free and depressing flaps of said sheet material.

1 7. A method of combining articles being delivered to an inlet position in a succession of input rows into a single output file of such articles for delivery to an output position, which method comprises propelling along a peripheral part of a closed circulation path directly to said outlet position a single file of said articles being delivered to said inlet position, and propelling other articles (hereafter referred to as "by-pass articles") in other files of said articles being delivered to said inlet position around said circulation path and returning such by-pass articles across the paths of other articles being delivered later in said other files, for delivery as opportunity arises to said peripheral part of said circulation path for merging there with articles being propelled in said single file directly to said outlet position.

18. An apparatus according to any one of the Claims 1 to 16, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

1 9. A method according to Claim 17, substantially as hereinbefore described with reference to and as illustrated by the accompanying drawings.