METHOD AND APPARATUS FOR NECKING AND FLANGING A METALLIC BOTTLE

An apparatus for continuously reforming an open end of a metallic can body has a plurality of sequentially aligned necking stations and a flanging station. An inspection station is sequentially aligned with the flanging station and has a camera for capturing a plurality of images about a circumference of the metallic beverage container as the metallic beverage container completes one full rotation about a generally vertical axis during a dwell period. A plurality of transfer wheels are sequentially aligned with the plurality of necking stations, the flanging station, and the inspection station. The transfer wheels sequentially transfer the metallic container between each of the plurality of necking stations, the flanging station, and the inspection station.

DETAILED DESCRIPTION

Referring toFIG. 2, a prior necking and flanging apparatus100for reducing a diameter of an open end of a metallic beverage container is illustrated.FIG. 2depicts metal container bodies10being fed along an indexed path300. This prior art apparatus has a plurality of necking stations. Ten such stations are shown, identified by numerals101-110, respectively. A flanging station112and a reformer station114are also shown. Three drive stations115-117drive the necking and flanging apparatus100. Sixteen transfer wheels119-134move the containers sequentially and in a serpentine indexed path104through the various necking, flanging and reformer stations. The transfer wheels119-134, as well as the necking, flanging, and reformer stations have gears in mesh with each other to produce a synchronized continuous drive means for all of the components.

A variable-speed drive feature of the drive stations115-117allows automatic increase and decrease speeds to match the quantity of containers flowing through the apparatus to the flow in the remainder stations of the apparatus. The variable-speed drive also allows an operator to accurately index the components of the system relative to each other, including managing dwell times at each station during which a beverage container is processed, e.g. receiving a reduction in the open end diameter by treatment with a set of forming tools.

Each of the necking station modules101-110are substantially identical in construction so as to be interchangeable, and can be added to or subtracted from the system depending upon the type of container that is to be formed. Each of the necking station101-110has a plurality of circumferentially-spaced individual, substantially identical necking substations. The number of stations and substations can be increased or decreased to provide the desired necking operation for various sizes of cans. This process is well known on the art. See, for example, U.S. Pat. No. 5,497,900.

The arrangement ofFIG. 2shows cylindrical metal container bodies10which are made of conventional materials in any conventional manner, being fed sequentially by suitable conveyor means (not shown) into the necking and flanging apparatus100. The conveyor means feeds the containers10to a first transfer wheel119, as is known in the art. The containers100are then fed serially through the various stations by the remaining interconnecting transfer wheels120-134.

More specifically, the first transfer wheel119delivers containers10to the first necking station101, where a first necking operation is performed on the container. The containers10are then delivered to a second transfer wheel120which feeds the containers10to a second necking station102where a second necking operation is performed on the container10. The container10is then removed from the second station102by a third transfer wheel121and fed to a third necking station103where a third necking operation is performed.

The containers are then sequentially moved through the fourth through tenth necking stations104-110to complete the necking operation. The necked containers10are next moved by transfer wheels131,132and drive station118to a flanging station112where a radially outwardly-directed flange30is produced on the container10, as is well known in the art, and is delivered to a transfer wheel133for delivery to a reformer station114where a bottom portion of the container is reformed to impart additional strength to the container.

All of the moving members in the necking, flanging and reformer stations are driven by a drive stations115-117, each of which includes a variable-speed motor connected to an output transmission. As will be discussed later, these motors can be controlled by a programmable controller housed, e.g., on a computer system to control the timing of the apparatus. Each of the transfer wheels119-134, as well as the necking, flanging and reformer stations have gears in mesh with each other to produce a synchronized continuous drive means for all of the components.

The variable-speed drive feature of drive stations115-118allow automatic increase and decrease of speed to match the quantity of containers flowing through the apparatus100to the flow in the remainder of the container line. The variable-speed drive also allows the operator to accurately index the components of the system relative to each other.

The present invention is primarily aimed at detecting manufacturing defects exhibited by an aluminum bottle after labeling and subsequent to necking, flanging and reforming as described above. Accordingly, the inventors contemplate that an inspection station as will be described below can be incorporated into the manufacturing process as an additional station or separate machine in a necking and flanging apparatus as described above. The description set forth below is consistent with that design. However, the inventors further contemplate that the inspection station150described below can be incorporated into almost any desired step of the aluminum bottle making process prior to palletizing the containers due the handling and transport mechanisms associated with the invention and the great flexibility of the inspection speed and aluminum bottle transport associated therewith. In such a manufacturing process, beverage containers are typically transferred from station to station by transfer wheels, conveyors, or some combination of the two and incorporation of the inspection station150can be achieved by sequentially aligning the inspection station at any point in the process.

Now referring toFIGS. 3-5, principles of the present invention are illustrated. The present invention comprises a necking and flanging apparatus100having and additional in-line inspection station150which receives containers10sequentially in the manner described above. Accordingly, the schematic apparatus ofFIG. 2is identical to the schematic representation ofFIG. 3, with the following exception. InFIG. 3, the apparatus100has an additional drive station118in operational communication with transfer wheel134, two additional transfer wheels135,136, and an additional inspection station150for automated inspection of the beverage container following the reformer station114.

The inspection station150includes image technology to capture and record desired images of the beverage container with one or more image recorders, preferably digital cameras200a,b,c. Line scan technology may be employed to take a beverage container image. A snap shot photograph of the beverage container is taken as the beverage container10or the camera200a,b,cis rotated to capture images of an entire circumference of the beverage container10. Preferably, the metallic beverage container10is rotated about a center vertical axis at one or more dwell positions during a predetermined time interval wherein indexing of the beverage containers10is paused to allow the photographs to be taken as the beverage container is rotated about a central vertical axis. Approximately 1024 photographs of the beverage container10are taken as it is rotating. Beverage containers10preferably maintain 1¼ revolutions for taking the preferable number of a plurality of individual photographs. The photographs are stitched together using a software routine to produce a composite image of the beverage container. The photographs are collected by a computer system204, which may comprise one or more computers and/or controllers in communication with one another, in communication with the cameras200a,b,c. The software routine is stored in a memory on the computer system204. Upon execution of the software routine, the composite image is created and outputted by the software. A further software may perform a pass/fail analysis on the composite image or any individual photograph or photographs to determine the surface quality of the beverage container10, primarily the existence or absence of surface defects such as dents, wrinkles, splits, scale, blemishes, and the like.

The individual photographs may capture an image of a section of the circumference of the entire height of the beverage container10, from the open end to the enclosed bottom portion. Alternatively, the individual photographs may capture an image of a section of a circumference of the beverage container10and only a portion of the height of the container. However, in either case, the composite image includes images of at least a portion of the entire height and the entire circumference of the beverage container10stitched together to form the composite image. Stated another way, a plurality of images of at least a portion of the height of the beverage container10from the open end to the enclosed end and about the entire circumference of the container are recorded and processed to arrive at the composite image.

In another embodiment, the individual photographs are taken of the open end from the flange30to the uppermost point of the sidewall18to capture images of the areas of the container most prone to forming defects, i.e. splits, wrinkles, scratches, fractures and the like. It should be noted that known automated prior art inspection techniques viewed containers from above downwardly. Therefore, a blind spot would occur in the shoulder region where the container undergoes its greatest amount of diametric reduction going from the sidewall18to the reduced diameter neck28. A camera angle from above could not focus on this area. The present invention eliminates the blind spot of the known prior art.

The inspection station150includes an indexer154for accepting the beverage containers10from a first transfer wheel135and sequentially transferring the beverage containers10along an indexed path comprising a plurality of dwell positions to a second transfer wheel136and delivery from the inspection station150to an exit conveyor (no shown) of the apparatus100.

The indexer154of the present invention is circumferential and rotates about a central axis. It has a plurality of pockets158adapted, as in sized and shaped, to support, control, and properly the sidewall of the beverage container10therein and to prevent misalignment of the beverage container through the inspection process. Each pocket has a turntable associated therewith, preferably a rotatable vacuum chuck164which utilizes a vacuum pressure to maintain the beverage containers10in position as the indexer154indexes or transports the beverage containers10through an inspection process as described above. Thus, the vacuum chucks164are each in fluid communication with a source of fluid pressure. The vacuum pressure is used to attach each beverage container10to the turntables. The vacuum chucks164are rotatable about an upright axis that is at least a substantially vertical axis, preferably a vertical axis. The rotation of the vacuum chuck imparts a similar rotation to an upright or substantially vertical beverage container10. The vacuum chucks164further include a chuck nose that fits within a bottom domed portion of the beverage container10to further support the beverage container10through the inspection process.

The vacuum chucks164are substantially free-wheeling. This enables a spinner belt168wound around a plurality of idler pulleys172to impart rotational movement to the beverage containers10attached to the vacuum chucks164. One of the idler pulleys172is operably joined to a spinner motor which in turn drives the spinner belt168. The spinner motor may be an ac motor.

The spinner belt168is preferably a 5 mm pitch timing belt and the pulleys172are 5 mm pitch. This driving belt represents a new way to use a timing belt. Usually a timing belt is used to make sure that pulleys move at the same time and at the same rate. The inventors use it to actually drive the vacuum chucks164, and they are all being tracked by a common encoder.

The encoder tracks rotational movement of the indexer turret and communicates the information to the computer for positional control. It communicates by taking the angular velocity of the pulley shaft and converting the information to digital data for use by the computer. There are actually two encoders, one for the indexer turret and one of the turntable information.

As shown, 8 vacuum chucks164are driven by the belt168, achieving an identical angular rotation. One advantage of this timing belt system allows the beverage containers10to be stationary (i.e. not spinning) at infeed and discharge. Because they are not spinning, a vacuum can be used to pick up the beverage container10. The angular rotation remains constant between the 8 vacuum chucks164. This also reduces potential beverage container10damage.

The inspection station150runs at300cans per minute or more. This is based on the combined move time and dwell time required by the process. As the move time and the dwell time are reduced, throughput is increased. In the future, the inventors contemplate that this invention will be capable of inspecting400to600containers per minute. If more limited inspection is performed, the number of inspections may exceed 1000 to 2000 containers per minute. A servo motor is used to control dwell and index time. Thus, the speed of the index and output of the software can be increased with decreased image or photograph acquisition time without swapping out parts of the apparatus.

Most available camera inspection systems are fixed speed. One advantage of the present apparatus is that a user can adjust the dwell time for the cameras200a,b,cdue to servo control. It follows that a user may also slow the rate or dwell down if more time is needed. Thus, a user may increase and decrease the rate as necessary or desires. Therefore, as camera technology improves and images can be obtained in less dwell time, the present inspection station150can automatically get faster. For example, as the inspection station index rate is increased, the rate at which the beverage containers10rotate must also be increased to ensure that we get more than 360 degrees of photos taken around the beverage container10. The adjustability of the dwell and index rate is one of the advantages of the servo technology.

A programmable controller which may be included with the computer system204is in communication with the inspection station150and the one or more servo motors which drive the indexer154and the transfer wheels135,136on the inspection station150. It can be used to program the indexer154to any predetermined dwell time independent of the speed of the necking and flanging apparatus100or conjunction therewith to ensure a continuous processing of beverage containers10through the apparatus100without any one station moving slower than another. In other words, the inspection station150is not a bottleneck operationally to the apparatus100. Thus, inspection station150can be programmed based on time without mechanical intervention. This is very important as other technology improves.

It should be understood that the inspection station150is programmable, and any number of dwell time preferences can be achieved on the same station150without the need for mechanical changes to the station150.

Furthermore, the controller is capable of synchronizing the movement of the indexer154with the overall apparatus100. It generally follows that the programmable controller which may be housed on the computer system204can be used to control the timing of not only the inspection station150but also the entire apparatus to ensure a smooth flow and processing of beverage containers10without unnecessarily long dwell times wherein containers10rest without being formed, reformed, flanged, or inspected. In other words, addition of the inspection station150into the apparatus100does not cause the apparatus100to require additional mechanical timing cams or other means, as timing can be controlled by the servos and one or more programmable controllers, such as one included on computer system204.

In one embodiment, a processing time is 200 msec times15pockets per turret (i.e.15chucks164), having a 24 degree index, yields inspection of 300 containers per minute. The beverage containers10are transported to the transfer wheel135and indexed to a transfer point to a vacuum chuck164on the indexer154. Each beverage container10rotates on the vacuum chuck164for at least a full 360 degree inspection.

The present invention uses line scan technology. It will take 1024 pictures per beverage container10. This allows the apparatus to take a strip of the beverage container10can at high resolution and build a composite image of 360 degree of the beverage container10one strip at a time. This allows the current apparatus to detect smaller defects.

For typical beverage cans, only a small uppermost portion of the can is necked radially inwardly. So for cans, the static technology only has to look at a small portion of the can, so it works well enough. However, for beverage containers10like those show inFIG. 1, there is a much longer neck, so there is more area of the beverage container10that must has be inspected. The present inspection station150allows increased inspection without adversely affecting the overall speed or output of the necking and flanging apparatus10. This is a very desirable advantage achieved by the apparatus of the present invention.

Furthermore, with a typical straight wall beverage can, an inspection device need only look downwardly to image the entire sidewall of the beverage can and defects can be seen from the inside looking radially outwardly. But with a beverage container10ofFIG. 1, inspection cannot be performed by looking inside to outside because the neck hole is very small and an inspection device (camera) cannot see down the internal walls of the shoulder26and sidewall18. As described above, the long-necked aluminum bottles have a blind spot created by the long neck28and the shoulder26. The present inspection station150eliminates the blind spot.

Current inspection is often performed by hand at a rate of about 10 beverage containers per minute. An inspector currently pulls a beverage container10from the production line and manually inspects it for 360 degrees and places it back on the manufacturing line if it passes. Obviously, it is cost prohibitive to inspect every container. However, 100% of the containers10receive manual inspection. The present invention will perform 100% inspection at a rate of 1 to 240 cans per minute, which keeps up with the current rate of manufacturing metallic beverage containers10that resemble bottles as shown inFIG. 1. Therefore, the inspection station of the present invention relieves a manufacturing bottleneck and/or lowers the cost of production.

It should be noted that more or fewer camera200a,b,ccan be utilized if needed. The inventors contemplate as many as 7 cameras for rotating containers and 2 for stationary containers, for a total of 9 cameras. Using additional cameras can help increase the speed of the inspection even greater. Or, different areas of the container can be inspected without losing or sacrificing speed of the overall apparatus10.

As shown inFIGS. 5 and 6, the inspection station may be outfitted with a rejection system. The can rejection system includes an ejector positioned along the indexed path associated with the indexer154for culling an individual beverage container10having a detected defect from the manufacturing stream of sequentially processed beverage containers prior to palletizing the defective container. The ejector may be a mechanical spring-loaded kick-out, a mechanical arm, pendulum, plunger, piston, plate, or grasping apparatus, or other mechanical system, but is preferably a blow-off nozzle180includes a source of fluid pressure182in which activation of same is either manually controlled or, more preferably controlled by a signal originating from a software routine stored in the memory on the computer200which compares the results of the camera inspection to a quality standard preset by the manufacturer. If, upon comparison of the inspected beverage container to the quality standard, the beverage container10is deemed to fail the quality standard, the fluid pressure is activated and delivered through the blow-off nozzle180to the beverage container10which thrusts the beverage container from the indexer154to a reject chute184and into a waste area, such as waste bin.

The ejector is located along the indexed path of the inspection station150. That is, the ejector is capable of removing a defective beverage container from the cue of beverage containers on the inspection station150. Accordingly, the ejector is located along the circumference of the indexer154after the cameras200a,b,cbut before the second transfer wheel136.

In terms of processing, a cue of a plurality of beverage containers enters the inspection station at an entry end via the first transfer wheel135. Each beverage container in the cue is transferred from the first transfer wheel135to the indexer154. Each beverage container is inspected by the cameras200a,b,cin conjunction with a software routine on the computer system204. If a beverage container does not meet a quality standard stored on the computer system, the computer system sends a signal to the ejector or source of power at an appropriate time when the defective beverage container is at or near the ejector wherein the ejector removes the defective beverage container from the cue prior to exiting the inspection station150at an exit end via the second transfer wheel136.

In one embodiment, an inspection station150is for inspecting a metallic beverage container having a closed bottom opposite an open end, and a cylindrical sidewall extending upwardly from the bottom to a circumferential shoulder against a preset quality standard. The inspection station150has an entry end and a first rotatable transfer wheel135adjacent thereto. The first rotatable transfer wheel135has a plurality of pockets, each adapted for receiving a beverage container10therein. A rotatable indexer154has a plurality of rotatable turntables164about a circumference thereof. The rotatable indexer154is rotatable about a central hub and each vacuum chuck164is rotatable about a center axis associated with each rotatable vacuum chuck164. A second rotatable transfer wheel136is opposite the first transfer wheel135and also has a plurality of pockets adapted for receiving beverage containers10therein. An indexed path of the inspection station150is defined by a portion of the plurality of pockets on the first rotatable transfer wheel135, a portion of the plurality of rotatable turntables on the rotatable indexer154, and a portion of the plurality of pockets on the second transfer wheel136. A plurality of cameras200a,b,care aimed at the indexed path about the circumference of the rotatable indexer154. One or more motors, preferably servo motors control rotation of the first and second rotatable transfer wheels135,136, the rotatable indexer154, and the plurality of turntables. An ejector is located along the indexed path. A computer system comprises a memory which stores and executes a software comprising a first routine controlling the means for rotating, a second routine controlling the plurality of cameras, a third routine comparing beverage container images against a preset quality standard, and a fourth routine for activating the ejector to remove a defective beverage container from a cue of beverage containers traversing the indexed path.

A shown inFIG. 7and as set forth above, the inspection station150can be placed in any physical location prior to palletizing the containers. InFIG. 7, the inspection station150is shown sequentially aligned with the necking and flanging apparatus100and a washing station400which rinses and dries the containers10subsequent to forming. Containers10are processed in the direction of the arrows and inspected subsequent to necking and washing but prior to palletizing.

The inspection of the beverage container10in a vertical orientation is important. Due to the weight distribution of the beverage containers10described herein, they cannot be transported well horizontally. In other words, one end of the container is much heavier than the other. The heavy end will drop first. It would be very difficult to transport and inspect the beverage container10while it was in the horizontal position because of the uneven weight distribution.

As used herein, the terms “first,” “second,” “third,” etc. are for illustrative purposes only and are not intended to limit the embodiments in any way. Additionally, the term “plurality” as used herein is intended to indicate any number greater than one, either disjunctively or conjunctively as necessary, up to an infinite number. The terms “joined,” ‘attached,” and/or “connected” as used herein are intended to put or bring two elements together so as to form a unit, and any number of elements, devices, fasteners, etc. may be provided between the joined, attached or connected elements unless otherwise specified by the use of the term “directly” and/or supported by the drawings. The phrase “sequentially aligned” is intended to indicate a manufacturing arrangement wherein items of manufacture can be transferred sequentially between manufacturing stations, and any number of manufacturing stations can be sequentially aligned without regard to the order of the manufacturing steps or processes carried out at each manufacturing station.