WO2012171062A1

WO2012171062A1 - Calibration method and device

Info

Publication number: WO2012171062A1
Application number: PCT/AU2012/000682
Authority: WO
Inventors: John Adam TURNER
Original assignee: Aci Operations Pty. Ltd.
Priority date: 2011-06-15
Filing date: 2012-06-15
Publication date: 2012-12-20
Also published as: AU2012269725A1

Abstract

A product simulation sample for calibration of a glass container quality inspection machine, the sample having a body made from a polymeric material which includes an engineered characteristic which simulates a quality characteristic of a glass container, said engineered characteristic being detectable by the quality inspection machine such that the machine can be calibrated to give the same response to detection of said engineered characteristic as a desired response to detection of the quality characteristic of a glass container which it simulates.

Description

CALIBRATION METHOD AND DEVICE

Field of the Invention

[0001 ] The present invention generally relates to a calibration method and device for calibrating quality inspection equipment of glass containers. The invention is particularly applicable for calibrating quality inspection equipment of glass bottles and it will be convenient to hereinafter disclose the invention in relation to that exemplary application. However, it is to be appreciated that the invention is not limited to that application and could be used to calibrate quality inspection equipment for any glass container, receptacle or the like.

Background of the Invention

[0002] The following discussion of the background to the invention is intended to facilitate an understanding of the invention. However, it should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was published, known or part of the common general knowledge as at the priority date of the application.

[0003] Glass containers formed in a container forming machine, such as an individual section (IS) machine, may have one or more defects that make the container unacceptable. It is important to frequently inspect glass containers during and after manufacturing to locate any problems in the manufacturing process. Any defective containers should be discarded and if the causes of the defect can be traced to any particular step in the manufacturing process, such as worn mould gear, that manufacturing fault should be rectified.

[0004] A number of quality inspection systems have been developed to identify defects in glass containers. Most quality inspection systems conduct automated inspections for flaws such as small cracks in the glass ("checks"), foreign inclusions ("stones"), bubbles in the glass ("blisters"), cracks, chips and line overs, sidewall defects, proper sealing of the finish on mouth of the container, dimensional adherence, and incorrect wall thickness. Additionally, automated inspections are made of the opening of the bottle to determine whether the opening is too small or whether the outside diameter of the finish is too large.

[0005] A large number of these quality inspection systems are set up and calibrated by placing a calibration standard in the inspection apparatus and manually adjusting various controls until the desired output is reached. Typically, an operator manually adjusts the inspection equipment if a defect sample fails to be rejected or if acceptable glass containers are rejected. Mechanical or software parameters may also need to be adjusted to ensure the inspection system is operating correctly.

[0006] Currently, these calibration standards comprise a sample glass container formed with one or more sample defects. The sample glass containers are used to calibrate, challenge and verify the quality inspection systems. The glass calibration standards used in the prior art can be relatively fragile, and therefore are not ideally handled by conventional machinery. Most glass calibration standards are therefore carefully aligned by hand during the calibration process.

[0007] Furthermore, it can be difficult to accurately provide a number of the defects in existing glass calibration standards. Glass calibration standards for critical defects are therefore not always available and where available may include sample defects that are not always repeatable. This can provide difficulties in setting the sensitivity of the rejection limits of individual sensors and detectors of a quality inspection system. Incorrect limit setting can either erroneously reject acceptable glass containers, which affects productivity, or accept containers with unacceptable defects, which affects product quality.

[0008] It would therefore be desirable to provide a new or alternative calibration method and calibration standard sample which can assist in more accurately calibrating the rejection limits of glass container quality inspection systems. Summary of the Invention

[0009] In a first aspect, the present invention provides a product simulation sample for calibration of a glass container quality inspection machine, the sample having a body made from a polymeric material which includes an engineered characteristic which simulates a quality characteristic of a glass container, said engineered characteristic being detectable by the quality inspection machine such that the machine can be calibrated to give the same response to detection of said engineered characteristic as a desired response to detection of the quality characteristic of a glass container which it simulates.

[0010] The product simulation sample of the present invention can be used to enhance consistent, reliable and repeatable verification of the glass quality characteristics inspected by glass container quality inspection systems. The present invention can therefore improve consistency, standardise quality protocols and detector rejection settings between individual quality inspection systems, individual glass production lines and/or plants. The present invention makes it possible for all glass container quality inspection systems in separate glass container manufacturing lines and plants to be calibrated to substantially the same desired detector responses for substantially all of the defects which the detectors and detector arrays of those quality inspection systems monitor and so that containers which satisfy the quality specification are not rejected as a result of inappropriate rejection settings.

[001 1 ] The product simulation sample has a body. Preferably the body will generally resemble the shape and size of a glass container which it is designed to emulate, although this is only required if aspects of shape or size are relevant to the quality characteristic of a glass container which the glass inspection machine is examining. In such a case, the shape and or size of the product simulation sample should approximate that of the glass container. However the sample may be engineered to be of a different shape or size to check that inspection machine gives the desired response to, say, an undersize, or out of round container. If shape or size is not relevant, for example, when the quality characteristic of a glass container is to check for stones, the sample may not need to look like a container such as a bottle at all, but it could be, for example, a solid cylinder. The engineered characteristic in this instance would be something that can simulate a stone in a glass container, and the inspection machine is "looking" for stones, rather than container shape.

[0012] The engineered characteristic must be made so that it is detectable by the inspection machine as if it were a quality characteristic of a glass container. The engineered characteristic need not necessarily be physically analogous to the quality characteristic of a glass container which it simulates but should be detected by the inspection machine as if it were physically analogous. For example, an inclusion in a glass container can be emulated by drilling a hole in the body of the simulation sample. An actual stone need not be inserted into the sample. This hole may be "read" or interpreted by the inspection machine as if it were an inclusion.

[0013] More than one engineered characteristic may be engineered into a single product simulation sample. It is preferable for the product simulation sample to include at least two engineered characteristics. This enables the calibration of inspection machine to be checked or recalibrated for two or more quality characteristics on the inspection of a single sample. Generally, three or more engineered characteristics can be included in a sample, in some cases five or more. The total number of engineered characteristics included in a product simulation sample is limited only by the detecting capability of the detectors in the quality inspection system, or where certain quality characteristics are mutually exclusive. For example, a sample cannot be engineered to be both "too short" and "too tall" at the same time.

[0014] In another embodiment of the invention there is provided a set of product simulation samples as previously described, wherein the set collectively includes engineered characteristics which simulate all of the quality characteristics for which it is desirable to inspect in a glass container by one or more quality inspection machines. [0015] In one embodiment all of the engineered characteristics equate to unacceptable engineered characteristics. For example, chips of a threshold size desired to trigger rejection is engineered into the body of the sample. The inspection machine can thus be calibrated so that its response to that size chip or larger is "FAIL".

[0016] In other embodiments there may be a plurality of engineered characteristics which define a range of quality characteristics in a glass container. That range may include a tolerance threshold of a quality characteristic of a glass container such that some of the engineered characteristics equate to an acceptable characteristic in a glass container and others equate to an unacceptable characteristic in a glass container. For example, chips of different sizes may be engineered into the body of the sample, some of the chips being smaller than an unacceptable dimension and others being larger than an unacceptable dimension. The smaller chips, while technically a defect, would not lead to rejection if they were found in a glass bottle. The larger chips would be an unacceptable defect in a glass bottle and if found in a glass bottle should lead to that bottle being rejected if an inspection machine is properly calibrated. By providing a range of defect sizes, the inspection machine can thus be calibrated so that its response to the chips smaller than the acceptable threshold is "PASS", and the response to the chips that are larger than the threshold is "FAIL".

[0017] Each of the engineered characteristics is configured to simulate a quality characteristic of a glass container so that it is detectable by the inspection machine as if it were a quality characteristic in a glass container. For example, the engineered characteristic can replicate a response for at least one of an unfilled section of the container, material damage, stress defect, shape variation, incorrect wall thickness, and faults in the finish.

[0018] There are numerous examples of the above defects. For example, material damage in a glass container can include at least one of foreign inclusions, internal bubbles, cracks, chips, line-overs or blisters. Additional examples include a damaged base, a split base, a ring blister, a crizzled seam. Examples of shape variations include a bent neck, out of round shape, a "leaner", and an internal bore fault. Examples of incorrect wall thickness include a thin heel, a thin shoulder, and a thin base. Examples of stress defects include a stressed side wall, base stress, or a stressed side wall. Examples of faults in the finish include an unfilled finish, an over-pressed finish, a sugary finish, and a split finish.

[0019] The engineered characteristic may be a physical crack/hole or flaw that is engineered into the product simulation sample. The engineered characteristic may be a machined area of the product simulation sample which when run through a glass container quality inspection system is seen by the system as an equivalent variable glass container dimension. Examples of engineered characteristics that replicate glass container quality defects include:

[0020] An unfilled section of a glass container replicated in the product simulation sample using at least one hole, aperture, detent, groove, trench or cavity located in a representative section of the product simulation sample.

[0021 ] A shape variation of a glass container replicated using a corresponding shape variation in a representative section of the product simulation sample which, in use, is located in a detection zone of the quality inspection system.

[0022] Material damage of a glass container replicated in the product simulation sample using at least one hole or cavity in a representative section of the product simulation sample.

[0023] A stress defect of a glass container replicated in the product simulation sample using at least one hole or cavity or at least one body, for example a wire, in a representative section of the product simulation sample. In some embodiments, the body is located in a wall of the container, preferably annularly set within a wall of the container and set flush with the outer surface of the container. [0024] A blister defect of a glass container replicated in the product simulation sample using a configured body integrally formed or inserted into a representative section of the product simulation sample.

[0025] The product simulation sample has a body which is constructed from a polymeric material. This material may have the same or similar colour to the selected glass material of the glass container being inspected by the quality inspection system, although this is not essential. For example, the product simulation sample may be made from green polymeric material when being used to simulate green or brown glass containers. Preferably the sample is made from colourless polymeric material when being used to simulate uncoloured glass containers. It is preferable for the product simulation sample to be transparent, and may have a similar refractive index to glass, although neither of these characteristics is essential.

[0026] Suitable polymeric materials from which the product simulation sample may be made include polyester (PES), polyethylene terephthalate (PET), polyethylene (PE), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polypropylene (PP), polystyrene (PS), polyamides (PA) (Nylons), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polycarbonate/acrylonitrile butadiene styrene (PC/ABS), polyurethanes (PU), melamine formaldehyde (MF), plastarch, phenolics (PF), polyetheretherketone (PEEK), polyetherimide (PEI) (Ultem), polylactic acid (PLA), polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTFE), urea-formaldehyde (UF) or the like. In a preferred embodiment, the product simulation sample is constructed of a resin, preferably an acrylic resin. In an exemplary embodiment the product simulation sample is made from an acrylic polymer material, and more preferably polymethyl methacrylate (PMMA).

[0027] The product simulation sample does not necessarily need to be constructed with exactly the same configuration as the equivalent glass container. The product simulation sample can therefore be hollow, solid or partially solid. In such a configuration, the sample need only include an engineered characteristic in a selected location which replicates a quality characteristic in a glass container.

[0028] The body of the product simulation sample can be constructed of any number of releasably connectable sections. For example, some product simulation samples may comprise a unitary body. The body of other product simulation samples may be formed from two or more releasably connectable parts. The use of two or more releasably connectable parts enables the product simulation sample to be formed in separate sections, which in some cases allows for easier manufacture and/or facilitates engineering of characteristics on the inside of a container which cannot be made in a container of unitary construction. The use of at least two releasably connectable parts also enables the product simulation samples to be supplied in a kit form, in which a user can selectively construct one or more samples using a number of interchangeable parts. Preferably, each of the releasably connectable parts includes different engineered characteristics.

[0029] The releasably connectable parts can be interconnected using any suitable connection structure. Suitable connection structures include (but are not limited to) friction fit, snap fit connectors, peg and hole connectors, fasteners, and complementary screw threads.

[0030] It can be advantageous to be able to locate and track the product simulation sample on a process line. For example, a product simulation sample may be mixed in with a number of glass containers in order to test the response of an inspection machine to a quality characteristic. It is important to be able to either visually or otherwise locate that product simulation sample in the event the sample is not detected or appropriately rejected by the quality inspection system. The loss of the sample amongst hundreds of glass containers can result in costly process down time to locate the sample or the rejection of a large batch of containers if the standard cannot be located. In one embodiment the sample may therefore have a secondary detection means, such as a distinctive visual colour to aid visual detection. In another embodiment the sample may include a tracking device, preferably an electronic tracking device, such as a radio frequency identification (RFID) tag.

[0031 ] The product simulation sample can be manufactured for a quality inspection system that inspects defects in any type, shape and/or configuration of glass container. Suitable containers include jars, bottles, drinking glasses and other mass produced containers although the invention may equally be used in the manufacture of cups, vases, or laboratory or other glassware.

[0032] In another aspect of the present invention provides a method of calibrating a glass container quality inspection machine. The method includes the steps of:

a. providing a product simulation sample having a body made from a polymeric material which includes at least one engineered characteristic which simulates a quality characteristic of a glass container and is detectable by the inspection machine;

b. presenting the sample to the inspection machine;

c. observing the response of the machine the engineered characteristic; d. comparing the response to the desired response to detection of the quality characteristic of a glass container; and

e. if said response does not match the desired response, adjusting the machine so that it provides the desired response.

[0033] In a glass container quality inspection machine there are generally two responses to a quality characteristic; PASS or FAIL, where a FAIL will lead to rejection of the container. In one aspect the detection sensitivity of a machine may require adjustment if the thresholds to detection of a characteristic have been inappropriately set. For example, the machine may have been programmed only to detect a characteristic above a certain limit or a sensitivity threshold. If it is decided that the sensitivity threshold is too high and it is desirable for the machine to detect the characteristic above a lower threshold, then by engineering a characteristic into the body at or around that threshold, the sample can be presented to the inspection machine and the machine's sensitivity adjusted so that so that it detects the engineered characteristic. In another embodiment the machine may be adjusted by reprogramming it to give the desired response to an engineered characteristic. For example, even though the machine may have detected a characteristic it may previously have been programmed to give a FAIL response. The FAIL response may have been programmed as a result of an overly conservative approach to a particular defect of a glass container, perhaps because it was not possible to set the machine close enough to a suitable threshold for rejection. By using the engineered characteristics of the sample as a basis for calibration, where the precision of those characteristics can be controlled and varied to a high degree, the inspection machine can thus be calibrated to a superior degree compared with the methods of the prior art.

[0034] A plurality of product simulation samples can be used provide a range of defects to tune individual detectors of the quality inspection system. Product simulation samples which include defects that fall within and outside of the rejection limits can be used to calibrate the exact rejection limits of the system. It should be appreciated that the product simulation sample in this method preferably comprises a product simulation sample according to the first aspect of the invention.

[0035] In some embodiments, the method can further include the step of modifying control software of the inspection machine to isolate a failure point if a product simulation sample fails to be detected. The engineered characteristics used in the product simulation sample can be categorised on severity, which can be used to determine a glass inspection machine isolation protocol.

Brief Description of the Drawings

[0036] The present invention will now be described with reference to the figures of the accompanying drawings, which illustrate particular preferred embodiments of the present invention, wherein:

[0037] Figure 1 shows three views of a first product simulation sample being a bottle for calibration of a glass bottle quality inspection system according to one preferred embodiment of the invention in which (A) is a perspective view of the bottle; (B) is a cross-sectional front view of the bottle; and (C) is an enlarged a cross-sectional side view a rim section of the bottle.

[0038] Figure 2 shows three views of a second product simulation sample being a bottle for calibration of a glass bottle quality inspection system according to one preferred embodiment of the invention in which (A) is a perspective view of the bottle; (B) is a partial cross-sectional front view of the bottle; and (C) is an enlarged detail view of a rim section of the finish of the bottle.

[0039] Figure 3 shows three views of a third product simulation sample being a bottle for calibration of a glass bottle quality inspection system according to one preferred embodiment of the invention in which (A) is a perspective view of the bottle; (B) is an enlarged detail view of a rim section of the finish of the bottle; and (C) is a perspective view of the base of the bottle.

[0040] Figure 4 shows two views of a fourth product simulation sample being a bottle for calibration of a glass bottle quality inspection system according to one preferred embodiment of the invention in which (A) is a perspective view of the bottle; and (B) is a partial cross-sectional front view of the bottle.

[0041 ] Figure 5 is provides a graph providing a comparison of the detected response from a quality inspection system for a glass bottle which includes a horizontal crack and a resin product simulation sample bottle according to the present invention including an artificially configured equivalent.

[0042] Figure 6 is provides a graph providing a comparison of the detected response from a quality inspection system for a glass bottle which includes a vertical crack and a resin product simulation sample bottle according to the present invention including an artificially configured equivalent. Detailed Description

[0043] Figures 1 to 4 show various embodiments of a product simulation sample for a glass container quality inspection system. Each of the simulation bottles 10, 30, 50, 70 comprises an acrylic resin bottle which include up to five engineered characteristics configured to be detected by the quality inspection system.

[0044] Each of the engineered defects in the simulation bottles 10, 30, 50, 70 has been manufactured with configuration which simulates a quality characteristic of a glass container. In most cases, the engineered characteristic has been configured to trigger a reject response in the quality inspection system, i.e. it is equivalent to a quality characteristic which constitutes a defect in a glass bottle. Various quality inspection systems are known in the art for inspecting glass containers, and in particular glass bottles. Selected examples of quality inspection systems are disclosed in United States Patent US 6,536,294 B1 and US 4,996,658, the contents of which are incorporated herein by this reference. It is to be understood that this product simulation sample could be used in any quality inspection system for glass bottle or glass containers.

[0045] The simulation bottles 10, 30, 50, 70 illustrated in Figure 1 to 4 are product simulation samples for glass beverage bottles, for example beer bottles. It should be appreciated that the present invention should not be limited to this bottle configuration, and could be applied to any type of glass container.

[0046] It should be appreciated that the simulation bottles 10, 30, 50, 70 are not constructed with exactly the same configuration as the equivalent glass container for which the simulation bottle is replicating defects. Each of the simulation bottles 10, 30, 50 and 70 are hollow and are constructed of two releasably connectable parts. For example, simulation bottle 10 shown in Figure 1 is formed of an upper section 12 and a lower section 14 which are interconnected by complementary screw threads 15. [0047] Each of the illustrated simulation bottles 10, 30, 50, 70 can have a distinctive visual colour in order to aid visual detection. Furthermore, one of more of these simulation bottles 10, 30, 50, 70 can include a radio frequency identification (RFID) tag to assist in tracking the bottle in a process line and when passing through the quality inspection system.

[0048] Figures 1 to 4 show simulation bottles 10, 30, 50, 70 which include a different set of engineered characteristics replicating defects typically found in a glass container. The engineered characteristic in each of these simulation bottles 10, 30, 50, 70 is formed as either a physical crack/hole, flaw or machined area that is manufactured in the bottle which is seen as that glass defect or variable glass container dimension when run through a quality inspection system.

[0049] Figure 1 illustrates a first simulation bottle 10 formed as a hollow bottle (best shown in Figure 1 (B)) formed of an upper section 12 and a lower section 14 which are interconnected by complementary screw threads 15. The outer shape has a similar configuration to a glass bottle equivalent including a cylindrical body 16, frustoconical neck 18 having an annular upper finish section 19 (best shown in Figure 1 (C)). The finish section 19 is configured to have a closure (not shown) fitted and sealed thereover. The cylindrical body 16 and frustoconical neck 18 are interconnected by shoulder section 20.

[0050] The first simulation bottle 10 includes four engineered characteristics. These are:

• Off center shoulder replicated by machining a cut out section 22 (Figures 1 (A)) in the shoulder section 20 of one side of the sidewall of the body of the bottle 10 in an area that is scanned by an out of round detector (not shown) when the simulation bottle 10 passes through a quality inspection system (not shown).

• An unfilled finish and split finish defect replicated by a recess 24 (best shown in Figure 1 C) formed in the top wall 25 of the finish section 19.

• A thin base defect replicated by a thin wall thickness section 27 (best shown in Figure 1 (B)) formed in the base 28 of the bottle 10. [0051] A crack or inclusion defect in the root of the neck 18 replicated by an aperture 29 (best shown in Figure 1 (B)) formed above the shoulder 20 of the bottle 10.

[0052] Figure 2 shows a second simulation bottle 30 formed as a hollow bottle (best shown in Figure 2(B)) formed of an upper section 32 and a lower section 34 which are interconnected by complementary screw threads (not illustrated) having a similar configuration as shown by screw threads illustrated in Figure 1 (B). The outer shape has a similar configuration to a glass bottle equivalent, including a cylindrical body 36, frustoconical neck 38 having an annular upper finish section 39 (best shown in Figure 2(A)). The finish section 39 is configured to have a closure (not shown) fitted and sealed thereover. The cylindrical body 36 and frustoconical neck 38 are interconnected by shoulder section 40.

[0053] The second simulation bottle 30 includes four engineered characteristics. These are:

• A bent neck by machining a cut out section 42 (Figure 2(A)) in the shoulder section 40 of one side of the sidewall of the body of the bottle 30.

• An out of round shape replicated by machining a cut out section 44 (Figures 2(A) and (B)) in one side of the sidewall of the body of the bottle 30 in an area that is scanned by an out of round detector (not shown) when the simulation bottle 30 passes through a quality inspection system (not shown).

• A thin heel by machining a cut out section 46 (Figure 2(A)) in the heel section 48 of one side of the sidewall of the body of the bottle 30 in an area that is scanned by a heel wall detector (not shown) when the simulation bottle 30 passes through a quality inspection system (not shown).

• A line over finish defect replicated by a raised section 49 (Figure 2C) formed in the top wall 43 of the finish section 39.

[0054] Figure 3 shows a third simulation bottle 50 formed as a hollow bottle, again formed of an upper section 52 and a lower section 54 which are interconnected by complementary screw threads (again not illustrated) having a similar configuration as shown by screw threads illustrated in Figure 1 (B). The outer shape has a similar configuration to a glass bottle equivalent, including a cylindrical body 56, frustoconical neck 58 having an annular upper finish section 59 (best shown in Figure 2(A)). The finish section 59 is configured to have a closure (not shown) fitted and sealed thereover. The cylindrical body 56 and frustoconical neck 58 are interconnected by shoulder section 60.

[0055] The third simulation bottle 50 includes six engineered characteristics. These are:

• A wire edge/over pressed finish replicated by an annular recess 62 (Figure 3(B)) formed in the top wall 63 of the finish section 59.

• A horizontal crack or ring defect replicated by forming cavity 68 (Figure 3C) underneath the ring 69 in the neck 58 of the bottle 50.

• A leaner in the base 65 of the bottle 50 replicated by machining a cut-out section 64 (Figure 3(C)) in the base 65 of the bottle 50.

• A stressed base replicated by forming an aperture 66 (Figure 3(C)) in the base 65 of the bottle 50.

• A crack or inclusion defect in the ring 67 of the finish 19 replicated by an aperture 68 (best shown in Figure 3(B)) formed above the ring 67 of the bottle 50.

• A stressed heel side wall (for example caused by a vertical crack) replicated by an aperture 69 (Figure 3(A)) formed in the heel 61 of the bottle 50.

[0056] Figure 4 illustrates a fourth simulation bottle 70 formed as a hollow bottle (best shown in Figure 4(B)) formed of an upper section 72 and a lower section 74 which are interconnected by complementary screw threads 75. The outer shape has a similar configuration to a glass bottle equivalent including a cylindrical body 76, frustoconical neck 78 having an annular upper finish section 79. The finish section 79 is configured to have a closure (not shown) fitted and sealed thereover. The cylindrical body 76 and frustoconical neck 78 are interconnected by shoulder section 80.

[0057] The fourth simulation bottle 70 includes four engineered characteristics. These are: • A stressed upper side wall (for example caused by a vertical crack) replicated by an aperture 81 (Figure 3(A)) formed under the shoulder 80 of the bottle 70.

• A ring blister replicated by an aperture 82 (Figure 5(B)) filled with white paint in the top surface in the top wall 83 of the finish section 79.

• A damaged base replicated by forming an aperture 84 (Figure 4(B)) filled with black paint in the base 85 of the bottle 70; and

• A crizzled seam replicated by a though hole type aperture 88 (Figure 4(B)) formed in the sidewalk

[0058] While not illustrated, it should be appreciated that the following defects can be replicated by the following engineering characteristics in any one of simulation bottles 10, 30, 50, 70 shown in Figure 1 to 4:

• A stressed heel side wall replicated by imbedding a wire, small object, black dot or the like in a sidewall, flush with the surface of the sidewall of the heel of a bottle; and

• A stressed upper side wall replicated by imbedding a wire, small object, black dot or the like in a sidewall, flush with the surface of the sidewall near the shoulder section of a bottle.

[0059] It should be appreciated that these types of imbedding defects may also be included in a simulation bottles made from glass.

[0060] Each of the simulation bottles 10, 30, 50, 70 shown in Figures 1 to 4 can be used to calibrate a glass bottle quality inspection system. The glass bottle quality inspection system typically forms part of a glass bottle manufacturing process, which can include for example an individual section (IS) machine for forming glass bottles.

[0061 ] Calibration of such a quality inspection machine can be achieved by passing each simulation bottle 10, 30, 50, 70 through the quality inspection system and analysing the detected response provided by that machine. The quality inspection system can then be calibrated to give the same response as a desired response to detection of that characteristic in a glass container based on a comparison of the detected response and an expected response from the quality inspection system.

[0062] It should be appreciated that calibration of the system generally relies on personnel adjusting the inspection equipment if a defect sample fails to be rejected or if acceptable glass containers are rejected. Mechanical or software parameters may need to be adjusted to ensure Inspection is operating correctly.

[0063] The simulation bottle 10, 30, 50, 70 is used to verify the correct operation of the specific applicable inspection on the machine. It should be appreciated that each specific simulation bottle 10, 30, 50, 70 on the quality inspection machine has a individual method of set up and calibration procedure.

[0064] Additionally, the defects or characteristics used in the product simulation samples can be categorised on severity, which can be used to determine a FP isolation protocol.

[0065] In some systems, control software of the quality inspection system can be modified to isolate a failure point if a product simulation sample fails to be detected.

[0066] Examples

[0067] Figures 5 and 6 provide a comparison of the detected response from a quality inspection system for a glass bottle defect and a polymeric resin product simulation sample according to the present invention including an artificially configured equivalent defect.

[0068] Figure 5 is provides a graph providing a comparison of the detected response from a quality inspection system for a glass bottle which includes a horizontal crack and a resin product simulation sample including an artificially configured equivalent defect similar to cavity 68 shown in Figure 3(B) underneath the ring 67 in the neck 58 of the bottle 50. As shown, the response distribution is statistically similar.

[0069] Figure 6 is provides a graph providing a comparison of the detected response from a quality inspection system for a glass bottle which includes a vertical crack and a resin product simulation sample a including an artificially configured equivalent similar to the aperture 81 formed in the neck 78 of the bottle 70 shown in Figure 4(A). As shown, the response distribution is statistically similar.

[0070] Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is understood that the invention includes all such variations and modifications which fall within the spirit and scope of the present invention.

[0071 ] Where the terms "comprise", "comprises", "comprised" or "comprising" are used in this specification (including the claims) they are to be interpreted as specifying the presence of the stated features, integers, steps or components, but not precluding the presence of one or more other feature, integer, step, component or group thereof.

Claims

We Claim:

1 . A product simulation sample for calibration of a glass container quality inspection machine, the sample having a body made from a polymeric material which includes an engineered characteristic which simulates a quality characteristic of a glass container, said engineered characteristic being detectable by the quality inspection machine such that the machine can be calibrated to give the same response to detection of said engineered characteristic as a desired response to detection of the quality characteristic of a glass container which it simulates.

2. A product simulation sample according to claim 1 wherein the body is made from an acrylic resin.

3. A product simulation sample according to claim 1 or 2 wherein said engineered characteristic simulates either an acceptable or non-acceptable quality characteristic in a glass container

4. A product simulation sample according to any one of the preceding claims wherein the engineered characteristic is not physically analogous to the quality characteristic of a glass container which it simulates but is detected by an inspection machine as if it were physically analogous

5. A product simulation sample according to any preceding claim, wherein the sample includes a plurality of engineered characteristics.

6. A product simulation sample according to claim 5 wherein said plurality of engineered characteristics define a range which includes a tolerance threshold of a quality characteristic of a glass container such that the desired response to some of said characteristics in said range is different to the desired response to other of said characteristics in said range.

7. A product simulation sample according to claim 5, wherein the size and configuration of the engineered characteristic are selected to test the reject limits of the quality inspection system.

8. A product simulation sample according to any preceding claim, wherein the engineered characteristic is selected from one of unfilled sections of the container, material damage, stress defect, shape variation, incorrect wall thickness, and faults in the finish.

9. A product simulation sample according to claim 8, wherein the material damage includes at least one of foreign inclusions, internal bubbles, cracks, chips, line-overs or blisters.

10. A product simulation sample according to claim 8, wherein an unfilled section of a glass container is replicated in the product simulation sample using at least one hole, detent, groove, trench or cavity located in a representative section of the product simulation sample.

1 1 . A product simulation sample according to claim 8, wherein a shape variation of a glass container is replicated using a corresponding shape variation in a representative section of the product simulation sample which, in use, is located in a detection zone of the quality inspection system.

12. A product simulation sample according to claim 8 or 9, wherein material damage of a glass container is replicated in the product simulation sample using at least one hole or cavity in a representative section of the product simulation sample.

13. A product simulation sample according to claim 8, wherein a stress defect of a glass container is replicated in the product simulation sample using at least one hole or cavity or at least one body imbedded in a representative section of the product simulation sample.

14. A product simulation sample according to claim 8, wherein a blister defect of a glass container is replicated in the product simulation sample using a configured body integrally formed or inserted into a representative section of the product simulation sample.

15. A product simulation sample according to any preceding claim, wherein the product simulation sample comprises at least two releasably connectable parts.

16. A product simulation sample according to any claim 15, wherein at least two the releasably connectable parts are interconnected using complementary screw threads.

17. A product simulation sample according to any preceding claim, wherein the product simulation sample includes a tracking device.

18. A product simulation sample according to claim 17 wherein said tracking device is an electronic tracking device.

19. A product simulation sample according to any preceding claim, wherein the product simulation sample is at least one of hollow, solid or partially solid.

20. A product simulation sample according to any preceding claim, wherein the product simulation sample is a bottle.

21 . A method of calibrating a glass container quality inspection machine, including:

a. providing a product simulation sample having a body made from a polymeric material, the body which includes an engineered characteristic detectable by the quality inspection machine and which simulates a quality characteristic of a glass container

b. inspecting the product simulation sample by the glass container quality inspection machine and observing the response of the machine to detection of said engineered characteristic; c. comparing said response to the desired response to detection of the quality characteristic of a glass container; and

d. if said response does not match the desired response, adjusting the machine so that it provides the desired response.

22. A method according to claim 21 , wherein a plurality of product simulation samples are used provide a range of engineered characteristics for calibration of said glass container quality inspection machine.

23. A method according to claim 21 or 22, further including the step of modifying control software of the inspection system to isolate a failure point if a product simulation sample fails to be detected.

24. A method according to any one of claims 21 to 23, wherein the product simulation sample comprises a product simulation sample according to any one of claims 1 to 20.