WO2009102964A2

WO2009102964A2 - Apparatus for testing containers, tray for holding cylinders and suction-basedchuck for robotic arm

Info

Publication number: WO2009102964A2
Application number: PCT/US2009/034067
Authority: WO
Inventors: James M. Khoury; William E. Donges; Jeff J. Morman
Original assignee: Nordson Corporation
Priority date: 2008-02-14
Filing date: 2009-02-13
Publication date: 2009-08-20
Also published as: WO2009102964A3; WO2009102964A4

Abstract

Apparatus for testing characteristics of a container includes a plurality of test stations in an enclosure. The containers are maneuvered by a gantry mounted robot. An optional suction device is provided that may also provide electrical ground for the container. A dedicated output buss may also be used as an interface between the test cell control system and a secure network.

Description

MULTIFUNCTION APPARATUS AND METHOD FOR TESTING CONTAINERS

Background

[0001] Containers, for example those used in the beverage industry, typically have inked decorations on the outside surface of the container, with the decoration having artwork and text in a variety of colors and patterns. The containers also typically are coated with an enamel or lacquer type clear coating over the decorative outside of the container, and clear or pigmented coating on the inside surface of the container. Much effort is expended by container manufacturers to control the thickness, uniformity and weight and additional or alternative characteristics of these ink patterns and coatings. As part of the control process, quality inspections and tests are routinely made, usually on a statistical sampling basis, to verify the quality of the finished containers. Similar issues are presented with shaped containers, such as for example, plastic beverage bottles. Many beverage containers are metal and referred to as two piece cans, in that they comprise a one piece formed cylinder body with an integral bottom or dome, and a closure is then welded or otherwise attached to the body to close the can.

[0002] Various tests may be used to verify the quality and characteristics of processed containers. For example, a current leakage test may be used to test for pin holes in the coating that lines the inside of the container. Various optical or contact tests may be performed to determine coating thickness both on inside and outside surfaces of a container. Decoration quality and color tests may be performed on the outside decoration. Coating weight may be determined by weighing a tare container and subtracting that weight from the weight of the coated container. These are some of the common tests performed for quality inspection, but many others may be known or later developed.

[0003] As is readily apparent, the wide variety of quality tests relating to characteristics of container coatings and decorations has resulted in a variety of testing apparatus due to the sometimes sophisticated nature of the test equipment. Each unique test is typically performed at a separate stand alone testing cell or apparatus. It is not unusual for a container inspection site to have two or more apparatus each for performing a specific test. Much time can be expended simply in moving test samples from apparatus to apparatus. Typically, all test data is likewise locally generated and stored and must be assembled together on a separate apparatus.

Summary

[0004] The disclosure presents a number of inventions relating to testing of containers and parts of containers such as lids, domes side walls and closures, for example. Containers may include, but are not limited to, two piece cans, shaped containers and container parts such as ends and closures for example. The inventions are described in terms of exemplary tests for coatings and inked decorations, however, the inventions need not be limited to any specific set of tests, and may include tests not described herein.

[0005] In accordance with a first inventive concept, apparatus for testing characteristics of a container comprises a multifunction testing capability within a testing area to facilitate performing two or more different tests on one or more containers. In one exemplary embodiment, a plurality of two or more test stations are positioned within reach of a container positioning mechanism. The container positioning mechanism is operable to position containers at each testing station. In another exemplary embodiment, the container positioning mechanism may be realized in the form of a multi-axis robot that can position and move a container anywhere within a testing area and in any angular orientation. [0006] In accordance with another inventive aspect of the disclosure, a tray is provided for holding and self-centering one or more cylindrical objects, for example, can bodies and other containers, so that a robotic mechanism is operable to pick up a cylinder from the tray and return the cylinder to the same location in the tray. In one embodiment, the tray comprises a flexible gasket having at least one opening therein that supports a cylinder by an interference fit about the periphery of the cylinder. In a specific embodiment, the gasket comprises natural rubber, but may comprise other suitable materials including materials that are FDA approved. In another embodiment, the tray comprises an electronically sensed identification system.

[0007] In accordance with another inventive aspect of the disclosure, system and method for identifying a rotational zero reference point on a container or workpiece are provided, hi one embodiment, a camera obtains an image of an outside identifiable feature on the container, and from that image determines a zero reference point for a robotic mechanism that is operable to rotate the container about a longitudinal axis of the container. [0008] In accordance with another inventive aspect of the disclosure, a chuck is provided for use with a robotic mechanism to allow the robotic mechanism to hold and release a container. In various alternative embodiments, the chuck comprises a suction device to hold a container, and a limit switch to indicate container height. [0009] In accordance with another aspect of the invention, a visual notification system is provided for allowing remote observation of test result or status for testing of containers in an enclosure. In an exemplary embodiment, the visual notification system comprises a light tower disposed on an outer surface of the enclosure, with the light tower providing warning and alarm indications that can be visually observed at a distance from the enclosure.

[0010] These and other aspects and advantages of the inventions disclosed herein will be understood by those skilled in the art from the following detailed description of the exemplary embodiments in view of the accompanying drawings.

Brief Description of the Drawings

[0011] Fig. 1 is an embodiment of an apparatus for testing containers, in perspective;

[0012] Fig. 2 is another embodiment of an apparatus for testing containers;

[0013] Fig. 2A is another embodiment of an apparatus such as Fig. 5 with a loading and unloading mechanism for containers;

[0014] Fig. 3 is an embodiment of a control arrangement for an apparatus such as shown in Figs. 1 and 2, for example;

[0015] Fig. 4 is an embodiment of a suction device for an apparatus such as shown in

Figs. 1 and 2;

[0016] Fig. 5 is another embodiment of an apparatus for testing containers, in perspective;

[0017] Fig. 5 A is an enlarged partial view of the apparatus of Fig. 5 from a perspective below the top of the enclosure;

[0018] Fig. 6 is a schematic illustration of an optical arrangement suitable for use with the apparatus of Figs. 1 and 5, and an alternative control system arrangement; [0019] Fig. 7 is an embodiment of a container tray, in perspective;

[0020] Fig. 8 is the container tray of Fig. 7 in exploded perspective;

[0021] Fig. 9 is a partial cross-section of the container tray in Fig. 7 taken along the line 9-9 of Fig. 7;

[0022] Fig. 9 A is a plan view of the container tray of Fig. 7;

[0023] Figs. 10, 11 and HA illustrate another embodiment of a suction device, illustrated in isometric and exploded isometric views respectively;

[0024] Fig. HA is a cross-section view of the suction device of Fig. 10 taken along the line 11 A- 11 A;

[0025] Fig. 12 is an exemplary screen shot for a setup and configuration routine for a control system that may be used with the apparatus of Figs. 1 and 5;

[0026] Fig. 13 is an exemplary screen shot for a tray data presentation of test results;

[0027] Fig. 14 is an exemplary screen shot for a data screen for test data acquired by an apparatus such as in Figs. 1 and 5; [0028] Fig. 15 is an exemplary graphic representation of test data acquired by an apparatus such as in Figs. 1 and 5;

[0029] Fig. 16 is an exemplary graphic representation of test data in 3D form by an apparatus such as in Figs. 1 and 5.

Brief Description of the Exemplary Embodiments

[0030] The present disclosure is directed to apparatus and methods for testing containers, such as, for example, but not limited to, cylinder shaped workpieces, two piece cans and shaped containers. The term "container" is intended to include container parts such as side walls, the dome or bottom of a two piece can, container ends and closures, to name a few examples. This is because for quality control, test and inspection during container production, a final container may not yet fully assembled and various parts may need inspection and test. The present inventions however, may also be used for finished containers and shaped containers. While the exemplary embodiments are described and illustrated in terms of specific structural and functional features, the inventions described herein are not to be construed as being limited to such specific features. For example, the exemplary embodiments are presented in the context of apparatus and methods for testing two piece can type containers and from one to six or more tests that can be conveniently performed within a single test cell or apparatus. However, the inventions may be used with a wide variety of container shapes, sizes, materials and decorations, as well as container parts such as side walls, domes, ends and closures, that can be positioned and moved relative to a test station, and the number and types of tests may be any number and type far beyond the exemplary tests described herein. While the exemplary embodiments show a mechanism for moving and positioning a container relative to stationary or fixed test stations, it is alternatively contemplated that the inventions may be used in apparatus wherein the container is stationary or moved to a stationary location from a loading station, and the test apparatus moved relative to the stationary container. Another alternative is an apparatus in which some test apparatus are moved relative to a stationary container, and others in which the container is moved relative to stationary test stations. Thus, the inventions herein contemplate relative movement between a container and a test apparatus. Moreover, while the exemplary embodiments use a robotic arm configuration, many alternative forms and functions of a container positioning mechanism may be used.

[0031] Additionally, the inventions set forth herein as well as the exemplary embodiments thereof, include descriptions of various exemplary tests and inspections that may be optionally performed in association with containers to measure, test and inspect various characteristics of the containers, including but not limited to characteristics of the ink, decoration and coatings. Such characteristics may include, for example, color, pattern, thickness, weight, uniformity, bar codes and so on to name a few of many possible examples. These descriptions are not to be construed in a limiting sense, and the apparatus and methods of the inventions herein may be used with many different types of test and inspection criteria and test methods and test apparatus for many different types of characteristics of a container. The tests presented herein include some that are commonly used with containers and others that may not be as commonly used but are now facilitated by the present inventions. Thus, the inventions herein are not necessarily directed to the specifics of the exemplary test apparatus and test methods per se but rather apparatus and methods that facilitate such testing techniques. Moreover, the inventions herein are not limited to the exemplary testing methods or sequences of steps described herein as they will be many available alternative ways to implement even the described tests apparatus, steps, sequence and methods herein. As an example, the exemplary embodiments herein describe a test method and apparatus for testing leakage current for assessing thickness of an internal coating as well as checking for pin holes and discontinuities in that coating. The described apparatus and method use an electrolyte disposed in the container. However, there are other well known and commonly used techniques to measure, test and inspect for the same thickness characteristics, such as the use of a contact probe. Therefore, the present inventions are not limited to the use of only the types of test apparatus and methods described herein, although as a general comment it is contemplated that at least two different tests will be performed.

[0032] The exemplary embodiments herein include additional detailed description that is intended to be exemplary in nature and not limiting, there being a wide variety of alternative structures and equipment for realizing and using the present inventions. For example, a single box-like enclosure is illustrated, but other enclosures may be used including multi-compartment enclosures, and in some cases a fully enclosed space may not be needed. Many different and alternative techniques may be used, both manual and automatic, to load or stage one or more containers in a test cell or enclosure. Still further, many different types of control systems may be used with the present inventions. [0033] While various inventive aspects, concepts and features of the inventions may be described and illustrated herein as embodied in combination in the exemplary embodiments, these various inventive aspects, concepts and features may be used in many alternative embodiments, either individually or in various combinations and sub- combinations thereof. Unless expressly excluded herein all such combinations and sub- combinations are intended to be within the scope of the present inventions. Still further, while various alternative embodiments as to the various aspects, concepts and features of the inventions—such as alternative materials, structures, configurations, methods, circuits, devices and components, software, hardware, control logic, alternatives as to form, fit and function, and so on— may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readily adopt one or more of the inventive aspects, concepts or features into additional embodiments and uses within the scope of the present inventions even if such embodiments are not expressly disclosed herein. Additionally, even though some features, concepts or aspects of the inventions may be described herein as being a preferred arrangement or method, such description is not intended to suggest that such feature is required or necessary unless expressly so stated. Still further, exemplary or representative values and ranges may be included to assist in understanding the present disclosure, however, such values and ranges are not to be construed in a limiting sense and are intended to be critical values or ranges only if so expressly stated. Moreover, while various aspects, features and concepts may be expressly identified herein as being inventive or forming part of an invention, such identification is not intended to be exclusive, but rather there may be inventive aspects, concepts and features that are fully described herein without being expressly identified as such or as part of a specific invention, the inventions instead being set forth in the appended claims. Descriptions of exemplary methods or processes are not limited to inclusion of all steps as being required in all cases, nor is the order that the steps are presented to be construed as required or necessary unless expressly so stated.

[0034] With reference to Fig. 1, an apparatus for testing characteristics of a container is generally designated with the numeral 10, and may also be referred to herein as a test cell 10. By test cell is meant that the apparatus 10 may be configured as a self contained, compact and/or modular unit that has a small footprint to facilitate its use in a testing or manufacturing facility. As used herein then, a "test cell" contemplates one or more test stations within reach of a container positioning mechanism such that a container may be loaded into the testing area, picked up by the container positioning mechanism, moved to one or more test stations and returned to the loading site, all within reach of the container positioning mechanism. The term test cell thus may include but need not include the use of an enclosure or partial enclosure. Alternatively, the test cell may define a testing area wherein the robot or positioning mechanism moves one or more test stations to a container. [0035] However, the inventions may also be used in apparatus 10 that would not be commonly referred to as a test cell or having all the features of the apparatus 10. For example, the apparatus 10 advantageously may include a box like enclosure 12 optionally including four side walls 12a-d, a top 12e and a floor or platform 12f. But in alternative embodiments, some or all of the walls surrounding the platform 12f may be omitted. The side walls 12a-d may optionally be transparent, such as made of clear plastic or alternative suitable material to permit an operator or inspector or other observer to view the operation of the apparatus 10. The optional top 12e not only may be used as part of the enclosure, but as will be further described herein below, may also be used as a support, or include a support structure for a gantry-style mounted container positioning mechanism. One or more of the side walls 12a-d may optionally include a door or access opening (not shown) to allow an operator access to the interior region of the enclosure 12, either for maintenance and repair or configuration of the system, or for manually loading and unloading containers being tested. In Fig. 1, two racks 14, 16 of test samples of containers 18 (also referred to herein with the reference letter C) of the same or varying size, shape and other characteristics are illustrated in an exemplary manner.

[0036] The enclosure 12 may further include an optional lower bay 20 having hinged doors 22 or other access means to house support equipment 21 shown in phantom (see also exemplary schematic of Fig. 3 herein) such as electronics used for the various test stations as may be included with the test cell apparatus 10. Additionally, electronics and other support equipment may be placed on top of the enclosure 12. Cabling such as hardwiring or network cables 24 may be used to link the test station electronics with a control system 26. The control system 26 may alternatively communicate with the various test station electronics via a wireless communication. The control system 26 may be realized in any convenient manner to control operation of the test cell 10 and its various components and test equipment. The control system 26 may also communicate via an optional bus 28 such as an open architecture bus like ANYBUSS™ , or as another alternative a serial bus such as an RS232, to exchange data and instructions with another system such as a PLC that provides a secure interface to a networked data system. For example, most factories run on secure networks with firewalls and other security measures to prevent hacking and loss of data and other confidential information. The use of an open bus design, facilitates control and data collection for the test cell 10, with communication on a dedicated but inexpensive bus 28 to a secure network without risk of the factory system security being compromised. This enhances the mobility and use of a test cell 10 as it can be relocated and reconfigured as needed, yet still has a simple and straightforward interface into a secure network if such is needed. Although shown physically separate from the apparatus 10, the control system 26 may conveniently be attached to or integrated into the enclosure 12 or the lower bay 20.

[0037] The optional enclosure 12, and alternatively just the platform 12F and the top

12e or other robot supporting surface, provide a testing area for a plurality of testing stations 30. In Fig. 1 only one exemplary testing station 30 (in this example, even the single test station 30 may include a plurality of probes or equipment for multiple tests at a single test station) is illustrated, however, it is contemplated that the test cell 10 concept facilitates two or more test stations, and in other embodiments illustrated herein there are six test stations provided. The present inventions however are not limited to any particular number or type of test station or test sequence performed at the various stations. The test station 30 in Fig. 1 is mounted from the enclosure top 12e, but could just as conveniently be mounted on the platform 12f or even one of the sidewalls 12a-d if so needed. The location of the various test stations, thus defining an overall testing area, is thus a matter of design choice and convenience.

[0038] The apparatus 10 further includes a container positioning mechanism 32 (also referred to herein as a robot or robotic device, with a robot being but one example of a container positioning mechanism), which in the exemplary embodiments herein may be realized in the form of an articulated set of robotic arms and positioning arrangements. The basic function of the container positioning mechanism or robot 32 is to control movement and position of each container 18 as it undergoes the tests prescribed for it. Note in Fig. 1 that the robot 32 is holding a container 18 generally upright for testing at the test station 30. Many different types of container positioning mechanisms 32 may be used, whether such mechanisms would be considered robotic or not. In the exemplary embodiments herein, the robot 32 may be, for example, model VP-G series available from Denso Robotics, Long Beach, California. This exemplary machine may include five axis free movement for three articulated segments 34, 36 and 38. These segments 34, 36 and 38 are moveable via a waist 40 which can rotate on a mounting base 41 about a vertical reference axis Y (as viewed in Fig. 1 for the mounting arrangement shown), a shoulder 42, an elbow 44 and a wrist 46. The wrist 46 may also include a container holding mechanism 48 that can rotate the container 18 about the longitudinal axis C of the container. In this example, when the container 18 is upright, its open end points up and the container axis C is about parallel with the reference axis Y. Although the exemplary robot 32 has a five axis movement, such complexity may not always be needed, although it is contemplated that the container positioning mechanism 32 will preferably be able to effect three independent axes of translational movement of the container, and also optionally and preferably rotation of the container at least about the longitudinal axis of the container. In some cases however, a container positioning mechanism may need less than three axes of movement depending how and where the containers need to be positioned and moved. In any case, the container positioning mechanism 32 may be selected so that a container 18 may be positioned at any test station 30 in the testing area and in any needed orientation (for example, but not limited to, upright, upside down, sideways, oblique and so on, facing in any direction as needed). The positioning capability of the positioning mechanism 32 will thus be optionally determined based on the overall test cell design, locations of the test stations 30, how and where the containers 18 are loaded into the test cell, how and where the containers are removed from the test cell, and so on. More than one container positioning mechanism 32 may be used for larger test cells if needed.

[0039] As is apparent from Fig. 1, the container positioning mechanism 32 may be gantry mounted, in effect upside down, from the top wall 12e. Although the gantry style mounting may be desirable in many applications, it is not required, and the container positioning mechanism 32 may alternatively be mounted on any of the walls 12a-d or the platform 12f. The location for mounting the container positioning mechanism 32 may be selected to optimize or maximize the usefulness of the apparatus depending on how many test stations there are, where the test stations are located in the testing area, and the design and configuration of the container positioning mechanism 32 in terms of its capabilities for positioning and orienting the containers. In many cases the gantry style mounting may be desirable as it frees up substantial real estate on the platform 12f for additional test stations, as well as arrangements for loading and unloading containers in the test cell 10, as will be further explained herein below with reference to Fig. 2.

[0040] The test cell 10 may optionally include locking casters 50 to facilitate mobility of the test cell 10, as well as leveling feet 52 for providing a fixed location. The feet 52 may be optionally equipped with vibration pads for isolating the apparatus 10 from building vibrations. This can be especially important for optical tests as data can be in error if the optical probes are subjected to vibration.

[0041] The container positioning mechanism 32 is controlled by appropriate instructions and control signals from the control system 26, so as to move and position a container 18 under test at each test station 30 in a selectable or programmable sequence. An exemplary embodiment of a control system 26 is described herein with reference to Fig. 3. The control system 26 may optionally be used to also control the various test station electronics and execute the test sequences as needed for each container. More than one container positioning mechanism 32 may be used for larger test cells if needed. The container positioning mechanism 32 includes the container holding mechanism 48 which may be designed in any one of many different choices and configurations. In the exemplary embodiments herein, the container holder mechanism 48 may be realized in the form of a suction device such as a suction cup that can grab onto the container bottom or dome. When suction is applied, the container 18 may be carried, moved and positioned by the container positioning mechanism 32, and the container 18 may be easily released by simply removing the suction force applied to the container dome. An exemplary embodiment of the holding mechanism 48 is described herein below with reference to Fig. 4 hereof. [0042] Alternatively, or in addition to, the bottom gripping container holding mechanism, the container positioning mechanism may be provided the ability to grip other parts of the container. For example, to perform side wall tests it may be desirable to grip the container dome, but for a dome test it may be desirable to grip a side wall. The container positioning mechanism may also be equipped to grip other container parts such as ends and closures. Suction may be used for gripping or other techniques may alternatively be used as needed. For example, steel containers may be held by an electromagnetic device. [0043] With reference to Fig. 2, another embodiment of a test cell 10 is illustrated. In this embodiment, many of the features described as to the first embodiment of Fig. 1 are the same, including a gantry mounted robot 32, the enclosure 12 and so on. This second embodiment includes three additional features. First, the apparatus 10 now is illustrated with additional optional test stations 30. Second, the apparatus 10 includes a container loading device 60 that may be optionally used for automatic loading of containers to be tested. Third, the apparatus 10 includes a container unloading device or container output 62. It should be noted that in some applications, the containers to be tested may be fed directly from a production line, or may be provided from another source. As another alternative, an apparatus 10 may include an automatic loader mechanism 60 and a manual loading area as in Fig. 1 or other convenient and alternative arrangements for automatic and/or manual loading of containers into the test cell, as well as other convenient and alternative arrangements for automatic and/or manual unloading of containers from the test cell 10 after testing is completed.

[0044] In Fig. 2 there is illustrated an inside thickness test station 30a. In this example, the inside thickness test station 30a (this is also the test station illustrated in Fig. 1) may be used to optically measure the coating thickness characteristics in a container interior, and as such may include one or more optical probes 64. As will be readily apparent from Fig. 2, the various test stations 30 may be mounted in any convenient location in the testing area for access by the robot 32. In this case, the inside thickness probes 64 are mounted from the top wall 12e, and may be optionally in the form of fiber optic cables or light pipes for example. The probes 64 may optionally include various angled probes to facilitate the test, such as a straight probe 64a that can be used for the coating thickness of the dome, a right angle probe 64b that can be used for coating thickness of the container inside wall, and a thirty or forty-five degree angle probe 64c that can be used for coating thickness inside the container at the chime region that can be a complex geometry transition between the dome and the wall. The actual angles used will depend on the type of analyzer and the container shapes, as well as the degree of control achieved with the container positioning mechanism 32. For example, for some analyzers the probe should direct light perpendicular to the surface being examined, and so the probe may be angled as needed to achieve that orientation. The positioning mechanism 32 may also help in the proper orientation. But other analyzers may not require or use a probe that is normal to the surface, and so the probe angles and positioning mechanism 32 may be used to obtain the desired orientation. The probes 64 produce optic signals that are fed back to an analyzer (not shown) which may be disposed on the top wall 12e or down in the lower bay 20 (Fig. 1) or elsewhere as needed. The specifics of the analyzer will depend on the type of analyzer used, and there are different optic analyzers available, such as from Sensory Analytics of Greensboro, North Carolina. Another system is disclosed in PCT publication WO 2006/027568 Al fully incorporated herein by reference. Non-optic thickness measurement techniques may alternatively be used. [0045] The robot 32 may be used to position the container relative to each of the probes for the selected tests. Although in this example the probes 64 are mounted on the top wall 12e, they may be mounted anywhere within reach of the robot 32 since the robot can position and orient the container as needed.

[0046] Also optionally disposed on the top wall 12e is a leakage current test station

30b. Such test is sometimes also referred to in the art as a milliamp or MA test, or metal exposure or ME test, basically checking for pinholes and coating uniformity characteristics such as areas of very thin coating thickness in the interior coating of the container. Alternative tests such as a contact probe device may be used for checking these characteristics. The ME station 30b may include, for example, a fill and empty tube 66 and an electrode probe 68. The tube 66 may be used to feed an amount of electrolyte into the

Il container interior, thus necessitating that the container be generally upright as in Fig. 1. The tube 66 may also be advantageously used to suction out the electrolyte after the test is completed, or another suction tube (not shown) may be used for this purpose. Optional level sensing (not shown) may be used to confirm that the right amount of electrolyte is in the container for the test. The electrode probe 68 may be connected to a voltage source (not shown) at an analyzer or other suitable electronic circuitry (also not shown) to measure or detect leakage current that may pass from the probe 68, through the electrolyte to the container 18 body. This test method is well known to those skilled in the art, but is greatly facilitated by the present inventions. Again, the ME analyzer may be any conveniently available system or custom system. As will be apparent, the container must be electrically conductive for this test and the container preferably although optionally must be electrically grounded. The container holding mechanism 48 may include means for providing electrical ground to the container, as described herein with reference to the exemplary embodiment of Fig. 4. Alternatively, the container may be grounded by other suitable techniques. [0047] The robot 32 orients the container upright, and positions it under the fill tube

66. After the electrolyte is placed into the container, the robot moves the container over to the electrode probe 68 and positions the container so that the probe 68 is inserted at the desired depth or depths in the container. After the test is completed, the robot 32 moves the container back to the tube 66 so that the electrolyte can be suctioned out. Typically the ME test will be one of the last tests performed as residual electrolyte may remain in some cases. [0048] Disposed on the platform 12f is a weight test station 30c, which may be a simple electronic scale device 70 available from Mettler-Toledo, Inc. of Columbus, Ohio. The scale 70 may be used to measure coating weight characteristic by comparing the weight of the container under test to an average weight or actual weight of an uncoated container. Again, an electronic circuit (not shown) associated with the scale 70 may be included with the scale 70, or separately in the lower bay 20 or the scale output may be fed directly to the control system 26. The robot 32 grabs the container, places it on the scale 70 and then releases the suction holding the container to the robot. After the weight is measured, the robot 32 grabs the container and moves it to the next test station.

[0049] Also optionally disposed on the platform 12f is a color analyzer 30d, such as available from Sensory Analytics noted above. This analyzer may be used to verify color accuracy and uniformity characteristics, for example, for example, of a decoration on the container. The robot 30 positions the container so that the analyzer 3Od can perform the test. The ability of the robot 32 to rotate the container about its longitudinal axis C (Fig. 1) can greatly facilitate the color test (as well as various other tests such as inside coating thickness, outside coating thickness, ink thickness and so on).

[0050] It is noted at this time that although in these exemplary embodiments the robot

32 is used to move the containers relative to stationary test stations, alternatively a robot may be used to move a probe relative to a stationary container, or a particular test cell may include both capabilities. Also, the various test stations are all optional ,may be used in any set of combinations, and additional test stations may be provided as needed. Some containers may undergo all the tests described in the exemplary embodiment while others may only have a few of the tests performed or even just a single test.

[0051] Additional optional test stations may include, for example, an exterior thickness test station 30e that may include an optical probe 72 for testing the outside or exterior surface coating thickness characteristics of a container. This sensor and associated analyzer (not shown) may conveniently be combined with the analyzer for the interior coating thickness probes 64, such as the system available from Sensory Analytics noted herein above. Alternatively, the outside thickness characteristic may be tested using the right angle probe 64b used for the inside wall coating thickness test. Also provided is an ink thickness characteristic test station 30f, which may include an optical probe 74, again operable with the Sensory Analytics system noted herein above.

[0052] In addition to using the container positioning mechanism 32 to move containers to and between test stations, the positioning mechanism 32 may be used to pick up and positioning testing pieces such as for example, color coupons, standard weights and so on to verify calibration of one or more of the various test stations. For example, calibration of the weighing test station may be verified by using the positioning mechanism 32 to pick up a test piece having a known weight, placing it on the scale 70 and having the system 26 confirm that the scale output is correct for the known weight, thus verifying that the weighing test station is calibrated. Any test station may be verified as to calibration in a similar manner by using the positioning mechanism 32 to move an appropriate test sample to the testing station to verify that the readings are correct.

[0053] Further illustrated in Fig. 2 is the container loading device 60. Many different arrangements may be provided for automatically and manually loading containers 18 into the apparatus 10. hi this example, the device 60 may be realized in the form of a simple chute or tray 76 which the containers can roll along into the test cell 10 from an entry point outside the enclosure 12. The containers 18 may be manually loaded into the chute 76 or fed into the chute from a feeder, for example a conveyor or other container moving device that loads containers into the chute 76. Containers may even be fed to the chute 76 directly from a production line or sampling line. A container detection device 78 may be used to detect when a container 18 is in position to be picked up by the container positioning mechanism 32. For example, the detection device 78 may be a proximity sensor or optical sensor or other convenient device that detects a container is in position and feeds a signal to the control system 26 that a test sequence or series of tests may be initiated. Alternatively, many other devices may be used to automatically load the containers, such as for example a conveyor belt.

[0054] Also in Fig. 2 is the container unloading device or output 62. The unloading device 62 may also be realized conveniently in the form of a chute, although other devices may be used as in the case of the loading device. In the embodiment of Fig. 2, the unloading arrangement may include two optional chutes, 80 and 82 with one assigned for "good" containers that pass the various tests applied to the container, and a "bad" chute for containers that fail one or more of its tests or otherwise is segregated out, such as a marginal pass for example. The robot 32 may be used to place a tested container in the appropriate output chute 80, 82 depending on the test results and criteria for separating the good from the bad containers. The output chutes may also be used to return containers to a production line or other location as needed.

[0055] Fig. 2A illustrates an alternative embodiment of a container loading and unloading arrangement, such as for example, the test cell 200 of Fig. 5 herein (for clarity, many of the details of the test cell 200 are omitted in Fig. 2A). In this embodiment, a container loading chute 500 may be supported on a stanchion 502 or other suitable support means. The loading chute 502 may comprise for example two rails 504, 506 that accommodate the containers C. The loading chute 500 may be used for manually loading containers into the chute or the chute may extend back to or be connected with an output from the container production line (not shown) for automatic loading. The containers C may easily roll down the loading chute 500 into the test cell 200 where the container positioning mechanism 32 has access to the container bottoms to pick up the containers for test. After tests are completed, a container may be placed in a "good" or "bad unloading chute 508, 510, each of which may be supported on a stanchion 512 or other suitable support means. A single unloading chute may be used, or more than two depending on the needs for a particular system. The unloading chutes may also be used to route the tested containers to another location as needed. The unloading chutes 508, 510 may be similar in design to the loading chute. [0056] Fig. 3 illustrates a simplified functional block diagram for a control system 26 interface with the various test stations. As illustrated, each test station 30 includes associated electronic circuits 90 (90a-f corresponding respectively to each test station 30a-f of Fig. 2) that collect test data and feed the data to a main controller 92 of the control system 26 The system controller 92 ^" may also interface with a robot control system 94 for controlling operation of the container positioning mechanism 32.

[0057] Containers typically include a bar code or other indicia that can be scanned to identify the type of container being tested. As illustrated in Fig. 3, the system controller 92 may interface with a bar code reader 96 or other scanning device needed based on the type of scanning being performed. The container positioning device 32 may be used to position a container within a range of the reader 96 to detect the bar code. Once the container is identified, the control system 26 may execute a selected series of tests for that container. Alternatively, an input device for the system 26 such as the illustrated keyboard 26a or other technique may be used for manually identifying the containers being tested. [0058] With reference next to Fig. 4, a container holding device 48 is illustrated in simplified form. The holder may include a base member 100 that can be mounted on the robot 32 wrist. The base member 100 carries a suction cup 102 that includes a through port 104 connectable to a vacuum source (not shown). When a vacuum is applied to the cup 102, the cup firmly grabs onto the container bottom or dome 106. In Fig. 4 the dome is illustrated with a slight concavity (as viewed from the bottom of the container 18). In many two piece cans, this concavity would be much more pronounced, and in monoblock type manufactured containers, may be flat or nearly flat. The exact shape of the dome is not critical, and the cup 102 shape and flexibility may be chosen to most easily be able to grip the dome under suction. The cup 102 may be flexible to allow it to spread out somewhat as it engages the dome to provide a strong seal and grip of the container 18. For systems that will need an electrical connection to the container body (for example, a grounded connection for an ME test), the cup 102 may be provided with one or more hard, sharp probes 108 that can pierce the coating on the dome as the cup 102 grips the container. The probes 108 may be attached to the cup 102 or integrated therewith such as by embedding or molding the probes 108 in place. An electrical connection 110 may be used between the probes 108 to provide the electrical potential for the container, such as ground for example. The base member 100 may also optionally include a series of notches or recesses 112 that receive or engage with a rim portion 114 of the container to help align and center the container with the cup 102 and the robot wrist. [0059] The apparatus 10 provides in the exemplary embodiments a self-contained testing unit for containers that is modular in design in the sense that the apparatus may be easily configured and reconfigured for accommodating a wide variety of container tests, particularly for tests related to coating and ink/decoration characteristics. Modularity may further be realized by providing a structure, such as the examples herein, by which the test stations, test area and/or container positioning mechanism may be moved or transported together as a unit or test cell. A wide variety and number of tests may be performed within a test area having a conveniently small footprint, thus eliminating the need for multiple independent testing apparatus. In some embodiments, the apparatus provides fully automated operation with in-line loading, with batch loaded operation capability. The apparatus 10 is preferably self-contained within an enclosure that circumscribes or encloses or protects the test area, whether the enclosure is multi-compartmented or not and whether the test area is fully enclosed or not, and optionally transportable system in which the test stations travel with the container positioning mechanism.

[0060] The control system 26 may be realized in many different ways including but not limited to programmable controllers, microprocessors, discreet circuitry along with well know support electronics and software design. The control system 26 may thus be programmed, in one exemplary manner, to operate the apparatus 10 in accordance with the following methodology. The exemplary tests and sequences herein are not critical and are only exemplary in nature. The containers are presented to the apparatus 10 either by manual loading, automatic loading or a combination thereof. The container presently under test may be identified such as by use of the bar code reader 96. Various test sequences, selections and recipes may be preprogrammed with the control system 26 or input by an operator through an interface such as a keyboard, memory devices, touch screens and so on. The information stored as correlated or indexed with the container identification may include items such as the container size, robot movement and measurement sequences, measurement ranges, good/bad criteria and so on. When a testing sequence begins, the robot grips the container bottom or dome and moves the container to the first test station such as, for example, a test for interior coating thickness. The container may then also be tested for over varnish/coating on the container exterior, and also weighed on the scale. Next the container may be positioned for the leakage current ME test, next the ink thickness and also the color tests. The tested container can then be placed at the outlet, for example, the good chute or bad chute. [0061] With reference next to Fig. 5, we show another embodiment of a test cell 200

(like components are given like reference numerals as used in the embodiment of Fig. 1 herein) that includes one or more optical probes 202, in this example three optical probes 202a, 202b and 202c that are mounted from the top of the enclosure 204 (the optical probes 202a-c may correspond to the optical probes 64a-c in Fig. 1 hereof). The number and type of optical probes 202 used will depend on the number and types of tests to be performed with the test cell 200. In this embodiment, there are three optical probes to test interior coating thickness of various simple and complex surfaces inside a can. Thus, each probe 202 may have a particular angle so that the probe can direct light perpendicularly onto a surface of the can. The optical probes 202 may also be used for various tests performed on the exterior surface of the can, including but not limited to the coating thickness of a varnish that is typically applied over the exterior printing, as well as various tests of the ink design including but not limited to pattern orientation, color quality and so on. Exemplary optical probes that may be used with the apparatuses herein are part no. 1089654 probe, 90 degree, 10 inch. TRANS-COATING; part no. 1087981 probe, straight, 10 inch, TRANS-COATING; and part no. 1087982 probe, 30 degree, 10 inch, TRANS-COATING, all available from Nordson Corporation, Westlake, Ohio. Many other probe designs may be used as needed including automated probes, that may be electronically controlled for different angles, so that a single probe may be used instead of two or more angled probes.

[0062] Also mounted optionally on the top of the enclosure 204 is a camera 206 and a light tower 208. A computer screen or monitor 210 may be mounted to the enclosure such as with a swivel bracket 210a for example, in this example on a side mount to a support rail 212 of the enclosure 204. The computer screen is operationally controlled by the control system 26 (in this embodiment of Fig. 5, the control system 26 may be located in the lower bay 20), and may be used, for example, to provide visual displays of test data, as well as used for system setup and configuration, as will be further described herein below. The camera 206 is positioned in such a manner that the container positioning mechanism 32 is able to present a container in the camera field of view. The camera 206 may be used to identify the exact position of a unique identifying feature of the container, for example, a corner of a bar code. Once the location of that feature is determined, the control system 26 can use that position for exact control of the container movements, particularly as a zero reference point for rotating the container about its longitudinal axis C. This methodology will be further described herein below.

[0063] The light tower 208 may be used to provide a visual indication to an operator or other observer as to test status, warning and alarms, even from a remote distance in which it would otherwise be difficult to observe the test information that is presented on the computer screen 210. In this example, the light tower 208 includes two light bands 214a and 214b, for example, yellow and red which are controlled by the control system 26. Yellow may be used as a warning signal to indicate that one or more test results have exceeded preset values, and red may be used as an alarm signal to indicate one or more test results are outside maximum limits. When such alarm or warning conditions are observed, an operator may then walk over to the computer screen and begin to review test data and other information to determine what caused the warning or alarm.

[0064] The enclosure 200 may also include a hinged door 216 for the lower bay 20.

In this example, the door 216 when raised to the position illustrated in Fig. 5 may latch, and thereby provide a support for equipment and materials, for example, a keyboard (such as the keyboard 26a of Fig. 1 for example). A power box 201 with ON and OFF switches 201a, 201b may be used as a master power control for the electronic and electrical equipment used with the test cell 200. An optional transformer (not shown) may be mounted to the enclosure 204 to allow connection to different power sources within a facility.

[0065] With reference also to Fig. 5 A, an optical analyzer 218, for example a spectrometer, is disposed on the top of the enclosure 204, along with a probe mounting block 220 which may be realized in the form of metal plate. Two support rails 205 a, 205b as part of the upper support structure of the enclosure 204 may be used to support the optical analyzer 218 and the probe mounting block 220, along with other equipment as needed, for example, the motor and electronics housing 207 for the gantry mounted container positioning mechanism 32. An enlarged support rail 212a may be used for routing power and data/signal cables (not shown) from the upper level of the enclosure down to equipment in the lower bay 20.

[0066] The optical probes 202 are mounted to the probe mounting block 220 using clamps 224a-c and extend downward therefrom. Fig. 6 schematically illustrates the optical arrangement in greater detail. The optical probes 202 are mounted to the probe mounting block 220. Each probe 202a, 202b and 202c has a respective light source 222, in this case 222a, 222b and 222c, associated with it (the light source 222 in practice may be physically located with the optical analyzer 218). A typical optical probe such as may be used with the apparatus herein may have a bundle of optic fibers that function to transmit light from a light source and direct that light at a surface being analyzed. This bundle of fibers typically surrounds a single fiber that functions as an output fiber. The output fiber receives light back from the surface being analyzed. Thus, as illustrated schematically in Fig. 6, above the probe mounting block 220 the fibers for each optical probe 202 are separated (as at 225) as to the bundle of six fibers that are coupled to the light source 222 and the single output fiber 226. The single output fibers 226, in this case three single output fibers 226a, 226b and 226c, for each probe may be routed to a three to one coupling or combiner 228. The three to one coupling 228 receives light from all three output fibers 226 and sends that light to a single optic fiber 230 that functions as an input fiber to the analyzer/spectrometer 218. This three to one coupling may be used because only one optical probe 202 is active at a time. The control system 26 controls the light sources 222a, 222b and 222c through a series of respective switching functions 232a, 232b and 232c (the switching functions 232 may be physically embodied in the analyzer 218 electronics, for example). Only one switching function is closed at any given time, since only one probe 202 is used, for example, inside a container, at a time. When a switch 232 is closed, power is delivered to the associated light source 222 so that light is transmitted down the probe 202 and directed against the surface being analyzed. Return light re-enters the probe 202 into the single output fiber 226 and passes through the three to one coupling 228 to the analyzer 218. The analyzer 218 converts the received light into data 232 that is transmitted to the control system 26 for further analysis and processing as will be further described herein below. For example, the control system 26 may convert the spectrometer data into information relating to thickness of a coating of the container interior surface at the location that the probes 202 direct light at the surface. [0067] As further shown in Fig. 6, the control system 26 operates to control the light tower 208, causing the yellow or red bands to be illuminated under specified conditions. The control system also controls the camera 206, the robot control 94, a bar code reader 96 and the monitor or display 210. Much of this peripheral equipment may be optional depending on the overall flexibility desired for a particular system.

[0068] With reference to Figs. 7-9 and 9A inclusive, a tray 234 for holding one or more containers is illustrated. Such a tray may be used, for example, to manually load containers C into the test cell. Although this embodiment is described for use with the testing apparatus 10, 200 herein, the tray concepts may find application and use with many different systems, including especially but not limited to robotic systems.

[0069] The tray 234 may include a gasket assembly 237 having a first or upper plate

236, a second or lower plate 238, and a gasket 239 that is sandwiched between the first and second plates. Screws 243 or other suitable means are provided to securely clamp the gasket 238 between the first and second plates 236, 238. The two plates and the gasket each have openings 240, 242, 244 respectively (see Fig. 9). Preferably these openings are round to easily accommodate cylindrical workpieces such as can bodies C one of which is shown in position in Fig. 7 (a can body C is partially shown in phantom in Fig. 9), however, other shapes may be used as needed, for example hexagonal, oval and so on. [0070] The gasket 239 openings 244 are sized so that a short annular lip 246 extends radially inward from the openings 240, 242 of the upper and lower plates 236, 238. The gasket opening 244 is sized so as to have a slight interference fit with a cylindrical wall C of the workpiece. In this manner, the gasket securely supports the cylinder while still allowing easy insertion and removal of the workpiece. The interior wall 248 that defines the gasket opening 244 may have a cylindrical profile as in Fig. 9 or may have other shapes and contours as needed. Due to the flexibility of the gasket and the slight interference fit, the gasket 239 will tend to orient a cylinder upright and be self-centered, even if initially the container positioning mechanism 32, or even a human, inserts the cylindrical body in at a cocked angle or off-center.

[0071] As illustrated with the can C in Fig. 7, in the test cell 10 apparatus the cans C may be inserted into the tray 234 upside down so that the bottom B of the can is up. This allows the container positioning mechanism 32 to grab the can from the bottom, lift it up out of the tray 234 and move the can over to a position for analysis and test. The container positioning mechanism 32 then returns the can to the tray 234 and releases hold of it. [0072] The gasket 239 may be made of any suitable material, and we have found that a natural rubber of about 40 durometer works well with thin walled metal cans, for example. However, other materials including other approved FDA materials may alternatively be used. The radial length of the lip 246 also affects its flexibility and so may be selected for optimum performance as needed. Although not required, by using a large number of screws 243, the gasket 139 is tightly clamped so that inserting a can into one opening will not disturb the gasket lip portions in the other openings. Alternatively, the gasket may be glued or bonded or otherwise attached to one or both of the first and second plates 236, 238. [0073] A third or bottom plate 250 is used to support the first and second plates 236,

238 and the gasket 239. Standoffs 252 secured by screws 252a may be used to provide a space between the gasket assembly 237 and the bottom plate 250. Indicia (not shown) such as numbering may be provided for each opening so that an operator may assign specific cans to specific locations in the tray 234.

[0074] Also provided with the tray is a tray identification system 254. In this embodiment, the tray identification system 254 includes one or more magnets 256 that are received in openings 257 in the third plate 250. Each magnet represents a binary code, for example, a 1 corresponding to the magnet being present and a 0 corresponding to a magnet being omitted. Thus for five magnets up to 32 different tray configurations may be uniquely assigned. The presence or absence of the magnets 256 is detected by suitable electronic devices, for example, proximity sensors 258 such as reed switches (Fig. 6) located, for example, flush mounted on the floor or platform 12f of the enclosure 204, or other suitable location. When a tray 234 is inserted in to the test cell, the proximity sensors detect the magnet pattern, and send appropriate signals to the control system 26 which then interprets the signals to identify the installed tray 234. Other tray identification systems may alternatively be used including but not limited to optical readers. Rails 260 may be provided on the platform 12f (Fig. 5) to guide and position the tray 234 as it is installed. Alternatively, locating posts or other mechanical interfaces may be used to assure that the tray 234 is properly installed in the test cell in the correct orientation. The magnets 256 may also be detected in order to confirm that the tray 234 has been fully and correctly positioned in the test cell so that the container positioning mechanism 32 can correctly locate and access one or more containers held in the tray 234.

[0075] The first and second plates 236, 238 and gasket 239 may also be provided with openings 261 (Fig. 9A) to assist in manually picking up the tray 234. The various plates may be made of any suitable material, for example, PVC or metal. Preferably the tray 234 is fairly heavy so that its position will not easily shift as containers C are removed and inserted. [0076] With reference to Figs. 10, 11 and 1 IA we illustrate another embodiment of a suction device 262 that is attachable to the end of the robotic arm, as for example the suction device 48 in Fig. 1 hereof. In this embodiment, the suction device 262 includes a holder body 264 and a mounting plate 266. The mounting plate 266 is attachable to the container positioning mechanism 32 by any suitable arrangement such as bolts (not shown) installed through mounting holes 267. Posts 268 extend from the mounting plate 266 and insert into bosses 270 formed in the holder body 264. The posts 268 allow relative axial movement between the holder body 264 and the mounting plate 266 while constraining lateral or radial movement, cocking and so forth to assure good alignment between the suction device 262 and a container. Screws 270 and washers 271 may be used to retain the holder body 264 with the mounting plate 266 together as a unit, but the holder body 264 is able to slide up and down along the axes of the posts 268, with the screws 270 preventing the separation of the holder body 264 from the mounting plate 266. Springs 272 may be disposed around each post 268 between the mounting plate 266 and the holder body 264. The springs 272 function to take up undesirable loads that might occur as a container is inserted into the tray 234 or if a container should accidentally hit something while the container positioning mechanism 32 is moving.

[0077] A suction cup 274 is provided that mounts into the holder body 264. The suction cup 274 in this embodiment includes a flexible web 276 that generally conforms to the shape of the container bottom that is to be held and moved. The suction cup 274 is easily changed in the event that different container shapes will be used. The suction cup 274 includes a central flow passage 278 that communicates with a transverse flow passage 280 in the holder body 264. A suction hose fitting 282 is attached to the outer port 280a of the flow passage 280 and is connectable to a suction or negative pressure source. The negative pressure source may be, for example, a vacuum pump 283 that is stowed in the lower bay 20 (Fig. 1). The control system 26 may control on and off times for the suction using an appropriate control valve, for example. When the suction cup 274 engages a container bottom, the suction applied helps to securely hold the container on the suction device 262. When suction is released the container easily separates from the suction device. [0078] The suction device 262 may be optionally equipped with a proximity sensor

284 that detects when a container has been captured by the suction device 262. The proximity sensor 284 produces a signal to the control system 26 that a container has been captured. For example, a magnet 284a may be used to indicate to the proximity sensor 284 that the robot 32 has contacted the container bottom and somewhat compressed the springs 272 by pushing down on the holder body 264. The control system 26 can use this information in several ways, including knowing that a container is properly seated in the suction device 262 before instructing the container positioning mechanism 32 to move the container to a testing location. Another example is that the control system 26 may use the proximity sensor 284 information to confirm that the container is the correct container expected in the tray 234. For example, if a wrong container has been inserted into the tray 234 and that container has a longer or shorter length than a correct container, the suction device 262 will contact the container either too soon or too late based on the movement of the robotic arm in a downward direction to pick up the container. If the proximity sensor 284 detects the magnet 284a too soon, then the system 26 knows that the container is taller than it should be, and if the proximity sensor 284 detects the magnet 284 either too late or not at all, then the system 26 knows that the container is either not present or is too short. Other uses for the proximity sensor 284 will occur to those skilled in the art depending on the particular system requirements. The control system 26 may also interface with a vacuum sensitive switch (not shown) which may be located, for example, in the lower bay 20 at the vacuum pump 283 that closes when a vacuum is detected, which corresponds to proper engagement between the suction device 262 and a container bottom (which may also be used as an indication that a container is too short).

[0079] The holder body 264 may also include one or more recess or grooves 286 that generally conform to the outer profile of a container bottom, especially the chime. This container will seat in this groove 286 which will help centering the container on the holder body 264, further improving the connection between the suction cup 274 and the container bottom.

[0080] In manual operation, an operator will load a tray 234 with one or more containers to be tested. During setup and configuration of the control system 26, the operator will select the type of container to be tested, which will include a test recipe that is stored in the control system 26. A tray is used that has an identification code that tells the control system 26 the type of container being tested. Once the tray 234 is properly inserted into the test cell, the operator simply activates a Start command and the control system 26 executes the programmed recipe of tests. For example, the container positioning mechanism 32 will move over and pick up one of the containers in the tray 234, and typically invert the container upright so that the open end of the container is facing up. The robot moves the container over to one of the probes (see Fig. 1 for example) and raises the container so that the probe faces the surface to be tested. Typical tests will be inside coating thickness for the various surfaces inside the container, including the sidewall, the chime, reverse sidewall, the mote, and the center dome. These various tests may include the use of more than one probe in order to be able to direct light perpendicular to the surface being analyzed, and the robot may also tilt the container off-axis (i.e. not upright) in order to achieve correct probe orientation. Some test recipes may call for the robot to rotate the container about its central longitudinal axis as well. Tests may also be performed on the outside surfaces of the container, including but not limited to coating thickness, ink patterns and alignment and so on. After the tests are completed, the robot returns the container to the same tray location. In automatic feed mode, containers enter the test cell through an inlet chute and are picked up by the robot for the tests being performed. After the tests are completed, the robot may be used to place the container in an outlet chute, or if two chutes are provided, in the good or bad outlet chute depending on the test results.

[0081] With reference to Fig. 12, we show a typical screen shot for a setup and configuration process or routine that may be used with the above described apparatuses. The level of complexity for the control software used with the control system 26 will be determined by the overall testing and data reporting needs, for example, of a quality control function or system monitoring function. Because the apparatuses described herein may be fully automated, it is useful that container samples right from a container production line are easily loaded into the test cell and with the actuation of a single control switch one or more containers may be tested in a short period of time, with automatic data collection and retrieval. Real time test data may also be presented.

[0082] hi Fig. 12, a select part drop down menu 300 may be used to identify the containers to be tested. With each part there is an associated test recipe that will be automatically carried out. The operator simply selects the Start Tray button 302 after the tray has been loaded into the test cell. A Stop Tray button 304 is provided if the operator chooses to interrupt a test sequence. A Can Position field 306 may be used to identify the type of container in each specific location of the tray 234.

[0083] A variety of additional drop down menus may be used as needed. A

Thickness Data tab 308 provides test data results, as illustrated in Fig. 13. A Can Info tab 310 pulls up the type of exemplary screen illustrated in Fig. 12. A System Configuration tab 312 may be used, for example, to provide instruction information such as where various system files are stored, to select whether the system will operate in manual or tray or track mode, and so on. Manual mode refers to an operator loading in a container or containers that may be identified, for example, using the bar code reader 96 (Fig. 6) which can be selected using the Scan Bar Code button 314. Tray mode refers to an operator using a tray 234 that has an associated identification code with it that will indicate to the control system 26 the type of containers therein without having to use the bar code reader. A Tray Info tab 316 may be selected to pull up a setup screen to assign container types to a particular tray identification code. Track mode refers to the automatic loading of containers into the test cell using a track arrangement such as the exemplary system illustrated in Fig. 2. [0084] A series of data fields provide specific information used by the control system

26 for testing the containers. For example, a container such as a 25 cl necked may have its bar code 318 assigned to it. Also, each container will have an associated recipe of the material being applied to the can interior surfaces and exterior surfaces. These coatings will have dry density values 320, 322 associated with them. The containers will also have diameter and height values 324, 326, as well as a bar code height vales 328 which will be further explained hereinbelow. Each test recipe may also indicate the number of test samples being made. For example, the system may take three samples along the height of the container and four samples about the circumference, and these values may be entered in the appropriate fields 330, 332. In such an example then, a 4x3 matrix of data will be collected, for example, for the inside wall or outside wall of each container. Additional fields indicate the probe operational criteria. For example, Fig. 12 illustrates the tab selection for the outside probe 333, meaning the probe that will be used to test the outside wall of a container. For example, a ninety degree probe 64b (Fig. 1) may be used for such a test. In addition to data concerning the probe itself such as wavelength data, the screen presents control information such as the Start Height and End Height value fields 334, 336 for the sidewall tests. Each container also includes alarm and warning values, for example, for the measured thickness or weight of the coating material. These values are indicated in the fields 338, 340. Similar information may be provided for the inside sidewall probe 335 and the inside bottom probes 337 by selecting the appropriate tab. For the inside sidewall, the same ninety degree probe may be used, for example, as was used for the outside sidewall. For the inside bottom of a container, the geometry may be much more complex as it may contain a chime, a mote, a reverse sidewall and the dome. Such tests may require the use of more than one probe, perhaps a straight probe 64c (Fig.l) and an angled probe 64a (Fig. 1) of thirty or forty- five degrees for example. The robotic mechanism may also tilt the container as needed for a particular inside surface so that the light is incident normal to the surface. [0085] A large easy to read data field 342 is presented and provides a readout of each data point as the test is performed. Thus, for example, for a 3x4 matrix of test data, the data presented in the data field 342 will change twelve times as the system steps through all the test points. This allows an operator to observe the real time test data.

[0086] In the exemplary screen of Fig. 12, the particular configuration is for reporting coating weight. Alternatively the control system 26 may report test results in terms of coating thickness. For a particular container, the Unit field 344 may be used to select whether data will be reported in terms of thickness or weight. For Fig. 12, weight is the selected unit of measurement. Thus, the data presented in the data field 342 is presented in units of mg/4in². If the units had been selected for indicating thickness of the coating layer, then the data in the data field may be in unit of microns, for example. In actual practice, the control system 26 may take the thickness measurements, and by knowing the total square area of the surface examined, as well as the dry density of the coating material, thickness data may be converted to the total weight value by multiplying the values per square area times to the total square area. This will be an estimated weight since only a finite number of data points are taken (for example twelve), but the number of data samples may be increased if so desired which will increase the accuracy of the total weight estimate. [0087] A Tray Data tab 346 may be selected to allow an operator to observe test data presented in a visual form that indicates the pass/fail status of each container in its tray location when the system is operating in Tray Mode. An example of such a screen is provided in Fig. 13. Note that the large readout data field 342 is provided so that an operator may observe each test value as the system steps through each measurement. A matrix 348 may be used to represent each container in its respective location in the tray 234 (as an option and previously noted herein, the tray 234 may include indicia thereon to indicate tray position for each container), hi this example the tray 234 has ten receptacles for containers. If a measurement exceeds one of the alarm or warning limits, the color of the can position field may be changed accordingly. Also, the color on the light tower 208 (Fig. 5) will also change. The data field 342 color may also change for values that reach the alarm or warning limits. [0088] Another illustration of presenting the test data to an operator or other user is presented in Fig. 14. In this example, all the test data for the Outside sidewall tests 350, the Inside sidewall tests 352 and the Inside Bottom tests 354 may be presented in table form, for example. Keeping with the 3x4 example above, the outside and inside sidewall tests will generate twelve data points for each container. The Inside Bottom tests 354 may include, for example, four data points for the reverse sidewall 356, four data points for the chime 358, one data point for the center dome 360 and four data points for the mote 362. The colors of the data values may also be changed when alarm and warning limits are reached for any particular test. This would be a typical screen the operator or other user might refer to, for example, if the light tower 208 had indicated a test result was at a warning or alarm level. The number of tests performed and data points taken is largely a matter of design choice. [0089] The flexibility of the testing apparatus is enhanced by many options for how the test data is presented. Figs. 15 illustrates test data— such as might be observed in the tabular form of Fig. 14~shown as a two dimensional color map. In this example the data is for the inside container tests including the sidewall 352, the chime 358, the mote 362, the reverse sidewall 356 and the dome 360 (note that the test results represented in Figs. 15 and 16 is not necessarily the same test results from Fig. 14). This color map is particularly useful in that it present the container coating profile in a top to bottom orientation along the vertical axis, and the horizontal axis represents the various points of rotation about the can inside circumference. Thus, the sidewall portion is a 3x4 matrix based on three tests done along the length of the sidewall at four different portions along the circumference. The test result for each test may be represented by a zone having a color that is based on the test result. Thus for example, at or near the top (T) of the container, four sidewall tests were performed as the can was rotated to produce four data values 366, 368, 370 and 372. Similarly, four sidewall data values 374, 376, 378, 380 were obtained in the middle of the container, and four sidewall data values 382, 384, 386 and 388 were obtained at or near the bottom (B) of the sidewall. Each of the chime, mote and reverse sidewall tests also produce four data values as the can is rotated. The dome in this example only produces a single data value 394 as typically only the thickness at the dome apex is of interest, but other dome data points may be obtained if so desired.

[0090] Each data value may be represented by the color of a zone of the map, with the color being based on a color code or key 396 which relates the color to whether the data value is in a good range or near and alarm or warning limit. Fig. 16 presents a three dimensional representation or contour map of the inside sidewall values of Fig. 15 and also illustrates an example of how the color code 396 may be utilized. Note that the contour map may be selected using an Inside Contour tab 398. A similar contour map for the outside sidewall may be selected using an Outside Contour tab 400. Contour maps may also be used for the other test data as needed.

[0091] As noted herein above, an optional camera 206 may be used to locate a zero reference position for rotational control of the container by the container positioning mechanism 32. Having a rotational zero reference point is not required for all tests. For example, interior coatings for containers are typically sprayed and do not have a profile associated with them. In other words, the coating distribution is intended to be rather uniform over the interior surfaces. Exterior coatings, and especially the ink designs, typically are rolled onto the exterior surface with specific beginning and end points. Therefore, in order to perform tests such as ink pattern alignment, it may be necessary to have a rotational zero reference point. The camera 206 facilitates this feature as follows. Each container having an ink pattern will have at least one unique identifier on the container. Most containers, for example, have a bar code that is located at a specific position on the container. The height of the bar code from an end of the container may be programmed into the control system 26 (see item 328 Fig. 12). The container positioning mechanism 32 picks up the container 18 and presents it to the camera 206 in a selected orientation (for example, upright parallel to the Y axis, Fig. 1) so that the bar code is within the camera field of view. The camera 206 takes a digital image of the container, and the control system 26 then analyzes the digital image to identify a specific feature location, for example, for the corner of the bar code. By knowing the exact position of a unique feature on the container when the container is in a known rotational position, this feature location may be used as a zero reference point for knowing where on the container a test is being performed during or after a rotation or partial rotation of the container. Therefore, test data may be directly linked to position of the test points relative to the rotational zero reference point. This may be used, for example, to verify ink pattern alignment.

[0092] The inventions have been described with reference to the exemplary embodiments. Modification and alterations will occur to others upon a reading and understanding of this specification. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims

ClaimsI claim:

1. Apparatus for testing characteristics of a container, comprising: a test station and a container positioning mechanism, said container positioning mechanism being operable to hold and to move a container from a first location to said test station and to return the container to said first location.

2. The apparatus of claim 1 wherein said test station and said container positioning mechanism are disposed in an enclosure.

3. The apparatus of claim 1 wherein said container positioning mechanism comprises a mounting base, said base being fixed to a surface, said test station being disposed on said surface.

4. The apparatus of claim 3 wherein said container positioning mechanism comprises a robotic device that is operable to pick up the container and selectively move the container along three orthogonal axes and rotate the container about a longitudinal axis of the container.

5. The apparatus of claim 4 wherein said robotic device comprises articulated segments and is operable to position the container in any orientation within a testing area, and to release the container after returning the container to said first location.

6. The apparatus of claim 1 comprising a device on said container positioning mechanism to hold and release a container.

7. The apparatus of claim 6 wherein said device comprises a suction device with a flexible cup that holds a container bottom by vacuum.

8. The apparatus of claim 1 wherein said container positioning mechanism is operable to move each of a plurality of containers from a respective location to said test station.

9. The apparatus of claim 1 comprising a bar code reader operable to identify the container.

10. The apparatus of claim 1 comprising a control system, said control system comprising a container positioning mechanism control and a test station control.

11. The apparatus of claim 10 wherein said control system identifies the container and executes test recipes based on said identification.

12. The apparatus of claim 1 comprising at least three test stations, said test stations comprising at least a coating leakage test station, coating thickness test station and coating weight test station.

13. The apparatus of claim 10 comprising a communication bus, said control system providing test data over said communication bus to a second control system that interfaces with a secure network.

14. The apparatus of claim 1 wherein said container positioning mechanism comprises a base that is gantry mounted on an upper wall of an enclosure.

15. The apparatus of claim 1 comprising a fill and empty mechanism, said fill and empty mechanism having a first mode of operation for placing a fluid in the container and a second mode of operation for removing fluid from the container.

16. The apparatus of claim 15 wherein said fluid comprises an electrolyte for testing coating leakage.

17. The apparatus of claim 1 comprising one or more optical probes for testing coating thickness.

18. The apparatus of claim 17 wherein said container positioning mechanism positions the container so that an optical probe extends into said first container interior volume.

19. The apparatus of claim 17 wherein said container positioning mechanism and at least two of said probes are mounted on a wall of an enclosure.

20. The apparatus of claim 19 wherein said container positioning mechanism comprises a gantry mounted robot.

21. The apparatus of claim 1 wherein the container comprises a two piece can body or a shaped container.

22. The apparatus of claim 1 comprising a loading area for a plurality of containers, said container positioning mechanism selectively moving each container from said loading area to said test station.

23. The apparatus of claim 22 comprising an inlet chute for automatic loading of containers in said loading area.

24. The apparatus of claim 22 wherein containers are manually positioned in said loading area.

25. The apparatus of claim 1 comprising first and second outlet chutes, said container positioning mechanism placing a tested container in one of said outlet chutes based on whether said tested container passed or failed selected tests.

26. Tray for holding cylinders, comprising: an upper plate, a lower plate secured to said upper plate, and a gasket sandwiched between said upper plate and said lower plate, said upper plate and said gasket having a plurality of openings therein, each opening in said upper plate being coaxially aligned with a respective opening of said gasket, so that a cylinder can be inserted through one of said upper plate openings and be supported by a portion of said gasket.

27. The tray of claim 26 wherein said gasket comprises natural rubber.

28. The tray of claim 26 wherein an annular lip of said gasket extends radially inward to a gasket diameter that is smaller than a diameter of a respective aligned opening of said upper plate.

29. The tray of claim 28 wherein said annular lip forms a cylindrical surface that fully contacts a cylinder when the cylinder is inserted into the tray.

30. The tray of claim 26 wherein said gasket comprises a flexible unitary body and supports each cylinder by an interference fit.

31. The tray of claim 26 wherein a plurality of cylinders are supported in the tray with each cylinder supported by a respective portion of said gasket.

32. The tray of claim 31 wherein each said portion of said gasket supports a cylinder without affecting other said portions of said gasket, and supports the cylinder about its entire periphery.

33. The tray of claim 26 comprising an electronically sensed identification system to indicate one or more characteristics of one or more cylinders disposed in the tray.

34. The tray of claim 33 wherein said identification system comprises a plurality of magnets on a surface of a third plate.

35. The tray of claim 34 wherein said first and second plates are supported above said third plate.

36. The tray of claim 35 wherein said first and second plates are supported by standoffs above said third plate.

37. The tray of claim 26 wherein each said portion of said gasket self-centers a cylinder installed into an opening of said upper plate.

38. The tray of claim 26 wherein each cylinder comprises a single ended can container.

39. A chuck for a robotic arm, comprising: a body having a plurality of concentric recesses, each recess receiving a rim portion of an associated container of corresponding diameter, and a suction member that contacts a lower surface of a container, a suction source in fluid communication with said suction cup so that when suction is applied the chuck can hold a container.