WO2006044104A1

WO2006044104A1 - System and method for inspecting and sorting molded containers

Info

Publication number: WO2006044104A1
Application number: PCT/US2005/034013
Authority: WO
Inventors: Benjamin L. Daniel
Original assignee: Owens Brockway Glass Container Inc
Current assignee: Owens Brockway Glass Container Inc
Priority date: 2004-10-20
Filing date: 2005-09-20
Publication date: 2006-04-27
Anticipated expiration: 2007-04-20
Also published as: EG25535A; SI1812176T1; GT200500300A; EP1812176B1; HRP20090582T1; PL1812176T3; JP4871874B2; CA2582446C; CR9025A; ES2333807T3; AR051225A1; RU2007118644A; RU2383399C2; JP2008516863A; CN101043956B; ZA200704031B; US7607545B2; KR20070065424A; MX2007004190A; EP1812176A1

Abstract

An apparatus and method for inspecting and sorting molded containers includes an inspection device (34) for inspecting containers and a container mold of origin identifier (22) for correlating a container that is determined to have at least one unacceptable commercial variation with the mold cavity that produced the container. A controller (16) having a programmed cavity reject threshold is in communication with the inspection device and the container mold of origin identifier for monitoring a commercial variation threshold to determine if a mold of origin has produced a threshold number of containers having a commercial variation outside the acceptable limits. A diverter (20) is in communication with the controller for segregating all the containers produced by a mold of origin determined to have produced the threshold number of containers having the commercial variation beyond the acceptable limits.

Description

SYSTEM ANP METHOD FOR INSPECTING AND SORTING MOLDED CONTAINERS

Field of the Invention

This invention relates generally to the manufacture of articles of glassware, and

more particularly to systems and methods for inspecting and controlling glassware

production.

Background of the Invention

In manufacturing of molded containers, such as glass bottles and jars, commercial

variations are often related to variations in the associated molds of origin. For this reason,

it is desirable in an automated manufacturing operation having a plurality of molds to

identify a specific container with its mold of origin, and the associated commercial

variations with molds of origin for repair or replacement of molds creating excessive non-

compliant or non-commercial product. The term "commercial variations" refers to

variations - e.g., dimensional variations that can affect the commercial acceptability of the

containers.

Individual section (IS) machines typically include a plurality of mold cavities and

automated apparatus for feeding glass gobs to successive molds to form the containers,

such as through blow molding. The blown containers are then fed by suitable conveying

apparatus to a lehr for annealing, and then to a so-called "cold end" where inspecting and

sorting are performed prior to packaging the containers for shipment. Desirably, the

packaged product is free from unacceptable commercial variations, such as may result

through problems developed over time in the molds. When problems do result,

particularly within the molds, it is desirable to detect the problems as quickly as possible so that the molds can be repaired or replaced to prevent the continued production of

containers having unacceptable commercial variations.

Summary of the Invention A method of inspecting and sorting molded containers, in accordance with one

aspect of the present invention, includes inspecting molded containers for commercial

variations outside of acceptable limits, setting a cavity reject threshold for at least one

unacceptable commercial variation, correlating a container that is determined to have at

least one unacceptable commercial variation with the mold cavity that produced the

container, and segregating all containers produced by a mold cavity after the mold cavity is determined to have produced a number of containers in excess of the set reject threshold

for the unacceptable commercial variation.

In another aspect of the invention, a system for inspecting and sorting molded

containers includes an inspection device that inspects containers to determine if a container has at least one commercial variation outside of the acceptable predetermined

limits. In addition, the system has a container mold of origin identifier adapted to identify

the mold of origin of a container determined to have at least one unacceptable commercial

variation. Further, the system has a controller in communication with the inspection

device and the container mold of origin identifier. The controller is operable to monitor at

least one programmable commercial variation threshold to determine if a mold of origin

has produced a threshold number of containers having a commercial variation outside of

the acceptable limits. The system also includes a diverter in communication with the

controller to segregate all the containers produced by a mold of origin determined to have

produced the threshold number of containers having the commercial variation beyond the

acceptable limits. Brief Description of the Drawings

These and other objects, features, advantages and aspects of the invention will

become readily apparent in view of the following detailed description of the presently

preferred embodiments and best mode, appended claims and accompanying drawings, in which:

Figure 1 is a schematic diagram illustrating a plurality of inspection lines

incorporating a method and system for inspecting and sorting molded containers according

to one presently preferred embodiment of the invention; and

Figure 2 is a process flow diagram for a controller used in the method and system for inspecting and sorting molded containers.

Detailed Description of the Preferred Embodiments

Referring in more detail to the drawings, Figure 1 illustrates a plurality of inspection lines 10, 12, 14, such as those used to inspect blow molded containers, for

example. The inspection lines 10, 12, 14 are primarily used to inspect various types of

attributes or commercial variations of the containers and communicate the inspection data

to an inspection data accumulator (IDA) 16. The IDA 16 is in two-way communication

with a controller or production information computer (PIC) 18 that is programmable to

establish the acceptable commercial variation threshold or upper and/or lower limits that

need to be attained for the finished containers. The PIC 18 communicates via the IDA 16

back to the respective inspection line 10, 12, 14 to direct a diverter 20 in each line to either

allow the finished product from the respective mold cavities to continue for further

processing, or to segregate the containers from a specified mold cavity having commercial

variations falling outside the preprogrammed acceptable limits. If the PIC 18 determines that a particular mold cavity is producing an unacceptable first ratio of acceptable versus

unacceptable product, then the PIC 18 directs the diverter 20 to reject or segregate 100%

of the subsequent product formed by the identified mold cavity, thereby rendering the

mold cavity as a temporarily rejected mold cavity. Desirably, only after the rejected mold

cavity produces a predetermined second ratio of acceptable versus unacceptable product

does the PIC 18 automatically instruct the diverter 20 to allow the acceptable product from

the previously rejected mold cavity to continue for further processing. The second ratio

may be the same as or higher than the first ratio.

As containers are being formed in the production mold cavities, a unique

identifying code is impressed into the bottom of every container, or otherwise encoded on

the containers, as desired. The containers are then fed or directed to a lehr 24 in a

predetermined sequence from the mold cavities. The lehr 24 tempers the glass through a

predefined heating and cooling process to provide the containers with the desired strength and finish characteristics.

The containers are preferably removed from the lehr 24 by a transfer device 26 and

then placed on a conveyor 28 for sequentially conveying the containers to the inspection

lines 10, 12, 14. Any number of inspection lines can be used to increase or decrease the

capacity for product flow, or a single inspection line could be used, as desired. Upon

entering the inspection lines 10, 12, 14, the containers preferably pass through a container

counter 30, such as a photoelectric eye, for example, which communicates the number of

containers passing thereby to the IDA 16, which in turn communicates with the PIC 18.

Thereafter, the containers preferably pass through an impact simulator 32 to test for

structural commercial variations, principally in the side wall surfaces thereof, generally by

applying pressure to a portion of the circumference of the side walls of the containers. Thereafter, the containers passing through the impact simulator 32 without being

rejected or broken are conveyed through an apparatus that includes a container mold-of-

origin identifier or cavity identifying device CID 22, diverter 20 and a finish product (FP)

machine 34, wherein the FP machine 34 desirably includes various types of inspection

devices. Suitable FP machines are disclosed, for example, US Patents 4,378,493 and

6,581,751. The CDD 22 can correlate each container with its mold of origin by reading the

unique identifying code on the container, such as discussed in U.S. Patent No. 4,644,851,

which is assigned to the applicant herein and incorporated herein by reference in its

entirety. At the same time, the FP machine 34 inspects the container for any number of

commercial variations, such as by way of example and without limitation, variations in

diameter, height, level of finish around the periphery thereof, commonly known as warp

and dip and cocked finish, and vertical and horizontal checks in the finish, as desired. The

mold of origin information and the inspection information are communicated to the IDA 16, and thus, to the PIC 18.

The PIC 18 utilizes the information received from the counter 30, CID 22 and FP

machine 34 to monitor at least one predefined programmable threshold, wherein the

threshold typically includes upper and/or lower limits for at least one of the commercial

variations that can be produced by the mold cavities. As such, the PIC 18 determines if

any one of the molds of origin is producing containers having at least one of the

commercial variations outside the acceptable threshold limits, and further determines if the

mold of origin is producing unacceptable containers in excess of a predefined acceptance

ratio of acceptable to unacceptable containers. If the PIC 18 determines that any one (or

more) of the mold cavities is producing unacceptable containers in excess of the

predefined acceptance ratio, the PIC 18 sends a signal back to the respective diverter 20 to

segregate and/or remove 100% of the containers formed by the identified mold cavity. As shown schematically in Figure 2, the PIC 18 can be programmed to account for

any number of commercial variations separately from one another or in consideration of

one another, as desired, to facilitate packaging containers falling within the predefined

acceptable limits and segregating out those that fall outside the predefined acceptable

limits. The segregated containers can be held for re-inspection and/or further

consideration of continued processing and inspection, or they can be removed from the

respective production line 10, 12, 14 thereby rendering them as unacceptable and not

suitable for packaging, as desired. The PIC 18 incorporates an automatic cavity rejection

(ACR) 36 feature that, when enabled, provides the PIC 18 with the ability to automatically

add a single identified mold cavity from an IS machine to a reject list 38, and potentially

reject the containers produced by the identified mold cavity without affecting the ability of

the remaining mold cavities from the IS machine from producing acceptable containers for

further processing. Therefore, the ACR 36 allows for targeted segregation of unacceptable containers traveling along at least one of the production lines 10, 12, 14 without

segregating an entire lot from the IS machine.

In order for the PIC 18 to determine if one or more of the mold cavities should be

added to the reject list 38, a cavity reject threshold is programmed into the PIC 18, such as

by plant personnel, preferably as a predetermined percentage for an unacceptable

commercial variation, referred to hereafter as an automatic reject threshold (ART) 40. The

ART 40 may be programmed for any number of commercial variations, and may include

different predetermined thresholds for each commercial variation, as desired. The ART 40

has a cavity first or "reject at" threshold 42 and a cavity second or "pack at" threshold 44.

The "reject at" threshold 42 is the ratio of unacceptable containers at which one of the

cavities is automatically placed on the reject list 38. This ratio is generally calculated as a

percentage of unacceptable containers produced by any single mold cavity verses the total number of containers produced by the same mold cavity over a predetermined amount of

time, such as ten minutes, for example. As such, preferably, the PIC 18 will not place a

mold cavity on the automatic reject list 38 until some preprogrammed number of

containers from the identified mold cavity are inspected. The "pack at" threshold 44 is the

ratio of unacceptable containers for automatically removing the cavity from the reject list

38 for the specified commercial variation for which it was automatically rejected.

For example, if a commercial variation, such as "out-of-round" for example, has a

"reject at" threshold set at ten percent, and the PIC 18, upon receiving inspection

information from the FP machine 34 over the predefined amount of time, shows that ten

percent or more of the containers produced by a particular mold cavity do not pass the out-

of-round inspection, then the responsible mold cavity will be automatically placed on the

automatic reject list 38. Accordingly, a signal is sent from the PIC 18 to the diverter 20 to

segregate 100% of the containers produced by the identified mold cavity. Thereafter, the

mold cavity will remain on the automatic reject list 38 until it is determined that the

percentage of unacceptable containers produced by the responsible mold cavity for the

commercial variation for which it was originally automatically rejected falls below the

"pack at" threshold 44, which is typically set as a reduced percentage from the "reject at" threshold 42, such as 8 percent, for example. Preferably, once a particular mold cavity is

automatically removed form the reject list 38, the mold cavity will not be subject to

another automatic rejection until a new batch of containers from a subsequent lehr

• operation is inspected. Otherwise, in order for the mold cavity to be removed from the

automatic reject list 38, plant personnel may manually override the ACR 36 system.

Desirably the system will indicate when a manual override has occurred, such as through a

visual display on a monitor of the PIC 18 for example, and that the containers continuing for further processing from the previously rejected mold cavity were not automatically

removed from the automatic reject list 38.

An automatic reject alarm threshold (ARAT) 46 can be programmed into the PIC

18 and enabled when or preferably prior to when the ACR 36 is enabled, to allow plant

personnel to be warned when any one of the mold cavities is close to being automatically

rejected by the PIC 18. The point at which the ARAT 46 is triggered preferably is

determined by the programmed instructions input by plant personnel into the PIC 18. The

programmed instructions direct the PIC 18 to recognize a programmed percentage of

rejected containers from any one of the mold cavities, wherein the alarm threshold 46 is

defined as a percentage of unacceptable containers in generally the same fashion as the

"reject at" threshold 42, however the alarm threshold 46 is programmed as a percentage

that is less than the "reject at" threshold 42. When the PIC 18 recognizes that the ARAT 46 has been reached, an alarm can be triggered via a signal from the PIC 18 to notify plant

personnel that proactive measures may need to be taken in order to prevent the mold cavity

from producing containers having unacceptable commercial variations in excess of the

"reject at" threshold 42. Accordingly, the ARAT 46 is operable to send a signal to indicate

when a mold of origin is producing a threshold number of containers approaching the

programmed acceptable ART 40 limits, or the "reject at" threshold 42, and thus, can assist

in preventing a mold cavity from being automatically rejected. As such, the ARAT 46 can

assist in reducing the number of potential disruptions to container production from any one

of the mold cavities. It should be recognized that the alarm can take the form of any

number of notification mechanisms, such as visual, audible or tactile alarms, a flashing

light, a flashing screen on the PIC 18, or other alerting mechanisms, as desired.

Desirably, when two or more inspection lines are being used, an inspection

integrity check mechanism is incorporated within the system to ensure that one of the inspection lines 10, 12, 14 is not rejecting acceptable product from one of the mold

cavities. The check mechanism is implemented by programming the PIC 18 to

automatically compare the reject percentages for each mold cavity between the separate

inspection lines 10, 12, 14. Desirably, the PIC 18 can be programmed to compare the

threshold number of containers having been determined to have an unacceptable

commercial variation from a specified mold cavity between the separate inspection lines.

As such, the PIC can be programmed to alert plant personnel if any one of the inspection

lines 10, 12, 14 is rejecting containers from a particular mold cavity in excess of a

predetermined programmed percentage differential, referred to as an automatic reject

difference threshold (ARDT) 48, over the remaining inspection lines. Accordingly, the

ARDT 48 can be used to alert the plant personnel, preferably through a similar alarm

mechanism as used for the ARAT 46, to a potential problem of one of the FP machines 34.

It should be recognized that upon reading the disclosure herein, one ordinarily

skilled in the art of inspecting systems and methods used in the inspection of molded

containers would readily recognize other embodiments than those disclosed herein, with

those embodiments being within the scope of the claims that follow. For example, it

should be recognized that any number of commercial variations may be checked in relation

to a separate set of the programmed percentages discussed above, and that the commercial

variations may be treated separately from one another. Additionally, any number of

commercial variations may be inspected in combination with one another, such that the

automatic rejection of a mold cavity, as discussed above, may be based on multiple

commercial variations in relation to one another for a single container. Accordingly, this

disclosure herein is intended to be exemplary, and not limiting. The scope of the invention

is defined by the following claims.

Claims

CLAMS:

1.

A method of inspecting and sorting molded containers, including the steps of:

a) inspecting molded containers for commercial variations outside of acceptable

limits; b) setting a cavity reject-at threshold for at least one unacceptable commercial

variation;

c) correlating a container that is determined to have at least one unacceptable

commercial variation with the mold cavity that produced the container;

d) segregating all containers produced by a mold cavity after the mold cavity is

determined to have produced a threshold number of containers as set forth in step b)

having said unacceptable commercial variation.

2.

The method set forth in claim 1 wherein step a) includes inspecting all containers

in a production line and step d) includes removing the segregated containers from the

production line.

3.

The method set forth in claim 1 wherein step a) includes inspecting containers

being conveyed along separate inspection lines and step d) includes comparing the

threshold number of containers having said unacceptable commercial variation from a

specified mold cavity between said separate inspection lines.

4.

The method set forth in claim 3 including providing an alarm indicative that one

inspection line is segregating a threshold number of containers in excess of another

inspection line.

5.

The method set forth in claim 1 wherein step b) includes setting an alarm threshold

that is less than said reject-at threshold for said at least one unacceptable commercial

variation and step d) includes triggering an alarm when said alarm threshold is reached to

assist in preventing the mold cavity from producing containers having unacceptable

commercial variations in excess of said cavity reject-at threshold.

6.

The method set forth in claim 1 wherein step b) includes setting a pack-at threshold

that is less than said reject-at threshold and step d) includes allowing the containers

produced by a previously segregated mold cavity to proceed for further processing when a

threshold number of containers from said previously segregated mold cavity exceed said

pack-at threshold.

7.

A system for inspecting and sorting molded containers, including:

an inspecting device (34) that inspects containers for at least one commercial

variation relative to predetermined acceptable limits for said at least one commercial

variation to determine if a container has at least one commercial variation outside of said

acceptable limits;

a container mold of origin identifier (22) adapted to determine the mold of origin

of a container determined to have at least one unacceptable commercial variation;

a controller (16) communicated with the inspection device and the container mold

of origin identifier and operable to monitor at least one programmable threshold for at

least one commercial variation to determine if a mold of origin has produced a threshold

number of containers having said at least one commercial variation outside of said acceptable limits; and

a diverter (20) communicated with the controller and operable to segregate all

containers produced by a mold of origin determined to have produced said threshold

number of containers having said at least one commercial variation beyond said acceptable

limits.

8.

The system of claim 7 wherein said controller (16) is operable to send a signal to

indicate when a mold of origin is producing a threshold number of containers approaching

said acceptable limits.

9.

The system of claim 7 wherein said controller (16) is operable to automatically

allow containers from a previously rejected mold cavity to continue for further processing.

10.

The system of claim 7 wherein said diverter (20) removes all the containers

produced by said mold of origin determined to have produced said threshold number of

containers having said at least one commercial variation beyond said acceptable limits.

11. The system of claim 10 wherein said controller (16) is operable to automatically