Source: http://www.google.co.uk/patents/US6592354
Timestamp: 2013-12-10 09:46:05
Document Index: 716705690

Matched Legal Cases: ['art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22', 'art 22']

Patent US6592354 - Part-forming machine having an infrared vision inspection system and method ... - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Advanced Patent Search | Sign inAdvanced Patent SearchPatentsA part-forming machine having an infrared vision inspection system and a method for verifying the presence, absence and quality of molded parts therein wherein an infrared vision system is utilized. At least one infrared sensor is used in conjunction with a part-forming machine, wherein the infrared...http://www.google.co.uk/patents/US6592354?utm_source=gb-gplus-sharePatent US6592354 - Part-forming machine having an infrared vision inspection system and method for verifying the presence, absence and quality of molded parts thereinPublication numberUS6592354 B2Publication typeGrantApplication numberUS 09/728,241Publication date15 Jul 2003Filing date1 Dec 2000Priority date1 Dec 2000Fee statusPaidAlso published asCA2447466A1, CA2447466C, CN1281396C, CN1487874A, EP1339536A1, EP1339536A4, US20020068106, WO2002043939A1Publication number09728241, 728241, US 6592354 B2, US 6592354B2, US-B2-6592354, US6592354 B2, US6592354B2InventorsEdward F. Kachnic, Benjamin J. PryhodaOriginal AssigneeAvalon Vision Solutions, LlcExport CitationBiBTeX, EndNote, RefManPatent Citations (22), Referenced by (10), Classifications (10), Legal Events (5) External Links: USPTO, USPTO Assignment, EspacenetPart-forming machine having an infrared vision inspection system and method for verifying the presence, absence and quality of molded parts thereinUS 6592354 B2Abstract A part-forming machine having an infrared vision inspection system and a method for verifying the presence, absence and quality of molded parts therein wherein an infrared vision system is utilized. At least one infrared sensor is used in conjunction with a part-forming machine, wherein the infrared sensor takes an image of the part and/or mold based on infrared radiation emitted by the part/mold. Based on the infrared image, the part-forming machine responds thereto by activating ejectors and reimaging the part/mold, or continuing with the next molding step.
a mold; means for ejecting at least one of the parts from said mold; means for controlling said ejecting means; an infrared sensor in view of said mold, wherein at least one of the parts formed by said machine is imageable by said infrared sensor and wherein said infrared sensor acquires visible images in the near infrared range; means for analyzing the image captured by said infrared sensor, said analyzing means generating an indication of the presence or absence of at least one of the parts, said analyzing means in communication with said ejection means, wherein said ejection means is responsive to said indication. 2. The machine of claim 1, wherein said ejecting means is at least one ram.
3. The machine of claim 1, wherein said means for controlling said ejecting means is a computer.
5. The machine of claim 1, wherein said analyzing means is a program.
6. The machine of claim 1, wherein said infrared sensor comprises at least one infrared camera.
7. An infrared sensoring system for use with a part-forming machine having a mold and a controller for operating the mold, said infrared sensoring system comprising:
at least one infrared sensor in view of the mold, wherein at least one of the parts formed by said machine is imageable by said infrared sensor and wherein said at least one infrared sensor has at least one near-infrared imager; at least one infrared emitting source; and means for analyzing the image acquired by said at least one infrared sensor, said analyzing means generating an indication of the presence or absence of at least one of the parts, said analyzing means in communication with said at least one infrared sensor and the part-forming machine controller, wherein the part-forming machine controller is respondable to said indication generated by said analyzing means. 8. The machine of claim 7, wherein said analyzing means is a programmable computer.
9. The machine of claim 7, wherein said analyzing means comprises a program.
10. The machine of claim 7, wherein said at least one infrared sensor is at least one infrared camera.
11. The machine of claim 7, wherein said at least one infrared sensor is a plurality of infrared sensors.
12. The machine of claim 11, wherein said plurality of infrared sensors are infrared cameras.
13. The machine of claim 7, wherein said infrared emitting source illuminates at near-infrared frequencies.
14. The machine of claim 7, further comprising at least one filter on said at least one infrared sensor for filtering out non-infrared frequencies.
15. A near-infrared sensoring system for use with a part-forming machine having a mold and a controller for operating the mold, said near-infrared sensoring system comprising:
at least one near-infrared sensor in view of the mold, wherein at least one of the parts formed by said machine is imageable by said at least one near-infrared sensor; and means for analyzing the image acquired by said at least one near-infrared sensor, said analyzing means generating an indication of the presence or absence of at least one of the parts, said analyzing means in communication with said at least one near-infrared sensor and the part-forming machine controller, wherein the part-forming machine controller is respondable to said indication generated by said analyzing means.
TECHNICAL FIELD The present invention relates generally to part-forming machines, and more specifically to a part-forming machine having infrared vision inspection capabilities and a method for verifying the presence, absence and quality of molded parts therein.
However, in view of the present system and method, the prior systems are disadvantageous. More specifically, the above systems have typically utilized charge coupled device (CCD) cameras to acquire an image of the mold. CCD cameras view objects within the visible light spectrum typically defined as electromagnetic radiation between 400 nm and 780 nm in wavelength and, as such, are dependent upon and affected by the lighting environment surrounding the molding machine. This lighting environment is typically difficult to control due to overhead fluorescent lights, sky lights, overhead cranes, machine operators and many other factors common in an manufacturing environment. Consequently, even slight changes in the lighting environment that occur while an image is acquired when compared to a previous image can and do cause false rejections of the inspected process.
Therefore, it is readily apparent that there is a need for a part-forming machine having a vision inspection system that is not affected by the various environmental lighting changes that can occur in a typical manufacturing setting and thus, can reduce the likelihood of false rejections. It is, therefore, to the provision of such an improvement that the present invention is directed.
SUMMARY OF THE INVENTION According to its major aspects and broadly stated, the present invention is a part-forming machine having an infrared or near infrared vision inspection system and a method for verifying the presence, absence and quality of molded parts therein.
Thus, a feature and advantage of the present invention is to provide a new and improved part-forming machine having infrared vision inspection capabilities that captures infrared or near infrared images of the mold and determines the presence, absence and/or quality of the molded part.
Another feature and advantage of the present invention is to provide a new and improved part-forming machine having infrared or near infrared vision inspection capabilities that reduces the number of false rejections in prior systems caused by environmental lighting.
Another feature and advantage of the present invention is to provide a new and improved part-forming machine having infrared or near infrared vision inspection capabilities that increases the accuracy of vision inspection systems thus increasing the efficiency of the part-forming process.
Another feature and advantage of the present invention is to provide a new and improved part-forming machine having infrared or near infrared vision inspection capabilities that can accurately function in any of a multitude of visible light intensities and settings.
Another feature and advantage of the present invention is to provide a new and improved method for verifying the presence, absence and quality of molded parts in a part-forming machine that utilizes an infrared or near infrared vision system.
Another feature and advantage of the present invention is to provide a new and improved method for verifying the presence, absence and quality of molded parts in a part-forming machine that is independent of the visible lighting of the part-forming machine environment.
Another feature and advantage of the present invention is to provide a new and improved method for verifying the presence, absence and quality of molded parts in a part-forming machine that reduces the number of false rejections, thus increasing the efficiency and productivity of the part-forming machine.
FIG. 1 is a perspective view of a typical injection molding machine equipped with an IR vision detection system;
FIG. 5 is a functional block diagram of a control of a prior art system known as the skip-eject system; and
FIG. 6 is a functional block diagram of a machine controller and analyzing means.
To better understand the present system and method of this invention, a rudimentary knowledge of a typical prior-art injection molding machine and process is helpful. Therefore, referring first to FIGS. 1-3, a conventional automated injection molding machine 10 is shown equipped with a mold 12 comprising two mold halves 14, 16, a sliding rod-type ejector system 18, and infrared (IR) sensor 310 for acquiring visual infrared or near infrared images of the open mold half 14 in electronic format that can be digitized, stored in memory, and processed to detect presence or absence of a plastic part or material in the mold half 14. In the preferred embodiment, the IR sensor 310 is an IR. camera; however, any IR sensor may be utilized.
After the liquid or molten plastic 40 is injected into the mold 12 to fill the mold cavity 50, as illustrated in FIG. 2, and after the plastic 40 in the mold cavity has solidified as described above, the ram 38 is actuated to pull the mold half 16 away from the mold half 14 so that the hard plastic part 22 can be ejected from mold cavity 50. The IR sensor 310 acquires a first image of the mold half 16, wherein the image is analyzed to ensure the presence of the part 22 in the mold half 16. Ejection of the hard plastic part 22, as mentioned above, can be accomplished by a variety of mechanisms or processes that can be made more efficient and effective by this invention, and the ejector system 18 illustrated in FIGS. 1-3 is but one example that is convenient for describing this invention. The ejector system 18 includes two slidable ejector rods 56, 58 that extend through the moveable platen 26 and through mold half 16 into mold cavity 50. When the mold 12 is closed for filling the mold cavity 50 with plastic 40, as shown in FIG. 2, the ejector rods 56, 58 extend to, but not into the mold cavity. However, when the mold 12 is opened, as shown in FIG. 3, an ejector actuator 60, which comprises two small hydraulic cylinders 62, 66 and a cross bar 68 connected to the ejector rods 56, 58, pushes the ejector rods 56, 58 into the mold cavity 50 to hit and dislodge the hard plastic part 22 and push it out of the cavity 50. Because one hit or push by the ejector rods 56, 58 is occasionally not enough to dislodge and push the hard plastic part 22 all the way out of the cavity 50, it is a common practice to cycle the ejector actuator 60 several times to cause the ejector rods 56, 58 to reciprocate into and out of the cavity 50 repetitively so that, if the hard plastic part 22 is still in the cavity, it will get hit and pushed several times, thus reducing instances when the hard plastic part 22 does not get completely ejected to a minimum. Then the IR sensor 310 which is focused on the mold half 16, acquires an image of the mold half 16, including the cavity 50, and sends the image in electronic form to an image processing system, where it is digitized and compared by a computer or microprocessor to an ideal image of the mold half 16 and empty mold cavity 50. If the image comparison shows that the mold cavity 50 is empty and that the hard plastic part 22 has been cleared from the mold half 16, the ram 38 is actuated to close the mold 12 to start a new molding cycle. On the other hand, if the image comparison shows that the hard plastic part 22 has not been dislodged from the cavity 50 or cleared from the mold half 16, then the ram 38 is not allowed to close the mold 12, and a signal is generated to notify an operator to check the mold, clear any residual plastic or the hard plastic part 22 from the cavity 50 and mold 12, and then restart the plastic injection molding machine 10.
As discussed above, the repetitive cycling of the ejector rods 56, 58 that is practiced in some conventional injection molding systems reduces occurrences of the hard plastic part 22 not being dislodged from the cavity 50 and removed from the mold half 16. However, for the many instances when one hit or push by the ejector rods 56, 58 would be sufficient to dislodge and remove the hard plastic part 22, which far outnumber the instances when additional hits or pushes by the ejector rods 56, 58 are necessary, the repetitive cycling of the ejector system 18 every time the mold 12 is opened also takes unnecessary time and causes unnecessary wear and tear on the ejector system 18 and mold 12. As an improvement, a skip-eject system, as found in U.S. Pat. No. 5,928,578 to Kachnic et al., is typically utilized, wherein the ejector system 18 is actuated only when necessary. For instance, instead of using a large, fixed number of ejector rod 56, 58 strokes or cycles for every time the mold 12 is opened in plastic part molding cycles, a variable number of ejector rod 56, 58 strokes is used to match each molding cycles ejection needs. The repetition of stroke cycles is dependent on the image of the mold 12 as obtained via an IR sensor system 300.
In the preferred embodiment, the IR sensor system 300 generally comprises IR sensor 310 and means for analyzing images 330 from the IR sensor 310 and for communicating the presence or absence of molded parts within mold halves 14 and 16 to the part-forming machine controller 72. The analyzing means 330 is preferably a computer programmed for analyzing the IR images to determine whether a part is present or absent in the mold 12 and then communicates the results to the part-forming machine controller 72. Given known parameters, one skilled in the art would be able to develop software for analyzing the IR or near IR images of the mold 12. The analyzing means 330 is preferably integrated with the part-forming machine controller 72; however, a separate controller/computer may be utilized that is communicationally linked with the part-forming machine controller 72.
The first IR or near IR image taken by IR sensor 310 is analyzed to ensure that the part 22 is present on the moving side of the mold. Next, a first cycle of ejector rods 56, 58 is performed. In one embodiment of the invention, as illustrated in FIG. 4, the ejector system 18 is actuated again after one cycle of ejector rod 56, 58 extension and retraction only when the second IR or near IR image recorded by the IR sensor 310 and analyzing means 330 indicates that the hard plastic part 22 has not been dislodged from the cavity 50 or cleared from the mold 12.
In the first state A illustrated in FIG. 4, the analyzing means 330 sends a mold close signal via an electrical interface 72 or via any other data communication means to the injection molding machine 10. In response, a close/open mechanism that includes a ram actuator actuates the ram 38 to close and press mold half 16 against the mold half 14 and followed by actuation of the plastic extrude system 42 to inject liquid or molten plastic into the mold 12 to form a plastic part. After allowing sufficient time for the plastic to harden, the process advances as indicated by arrow 76 to state B in which the ram 38 is actuated to pull mold half 16 away from mold half 14. When the mold 12 is open as illustrated in state B, an IR or near IR image of the open mold half 16 is acquired by IR sensor 310 and transmitted via electrical cable 78 to the analyzing means 330, which compares the image to an ideal image of the mold half 16 as it should appear with a properly formed plastic part 22 in the cavity. This comparison function of analyzing means 330 is indicated in FIG. 4 by decision block 80. At this point in the sequence, there should be a fully formed hard plastic part 22 in mold half 16. Therefore, if the comparison at decision block 80 indicates that no plastic part 22 is present in mold half 16 or that plastic part 22 is present but incompletely formed, the analyzing means 330 stops the sequence and generates a signal to an alarm 82 or other device as indicated by arrow 84, to signal an operator 86 to come and check the injection molding machine 10. However, if the comparison indicates that a fully formed plastic part 22 is present in the mold 12, as it is supposed to be, the analyzing means 330 causes the sequence to continue, as indicated by arrow 88, to state C by sending a signal via the machine controller 72 to actuate the ejector system 18 to extend the ejector rods 56, 58 to cycle once to hit or push the hard plastic part out of the mold half 16. However, as discussed above, occasionally, one extension of ejector rods 56, 58 will not dislodge or clear the hard plastic part 22 from mold half 16. Therefore, the analyzing means 330 causes the sequence to proceed as indicated by arrow 90 to state D.
In state D, the analyzing means 330 acquires another IR or near IR image of the mold half 16 from IR sensor 310 via cable 78 and compares it, as indicated by decision block 92, to an ideal image, which is stored in memory, of the mold half 16 with the hard plastic part 22 removed and the mold cavity 50 (not seen in FIG. 4) empty. If the comparison at decision block 92 indicates that the part 22 is cleared and the cavity 50 is empty, the analyzing means 330 continues the sequence as indicated by arrow 94 back to state A by sending a signal via the machine controller. 72 to actuate the ram 38 to again close the mold 12 and to actuate the extruder system 42 to again fill the mold 12 with plastic. On the other hand, if the comparison at decision block 92 indicates the part 22 is stuck in the mold half 16 as indicated by phantom lines 22′ or otherwise not cleared, then the analyzing means 330 proceeds as indicated by arrow 96 to check the number of times that the ejector rods 56, 58 have been extended or cycled. If, as indicated at decision block 98, the ejector rods 56, 58 have been cycled more than some reasonable number, such as five (5), in unsuccessful tries to dislodge and clear the part 22 from the mold half 16, the analyzing means 330 stops the sequence, and, as indicated by arrow 100, proceeds to signal the alarm 82 or other device 86 to call the operator. However, if the number of tries has not exceeded the number, such as five (5), the analyzing means 330 returns the sequence to state C, as indicated by arrow 102, by signaling the ejector actuator via the machine controller 72 to again fire or cycle the ejector rods 56, 58 to hit or push the part 22 once again. The analyzing means 330 then continues the sequence again as indicated by arrow 90 to state D where another IR or near IR image of the mold half 16 is acquired with IR sensor 310 and compared again at 92 to the ideal image of how the mold half 16 should appear with the part cleared. If the part 22 was successfully cleared by the last extension or cycle of the ejector pins 56, 58, the sequence proceeds as indicated by arrow 94 to state A. However, if the comparison at 92 indicates the part 22′ is still stuck or not cleared, the analyzing means 330 checks the number of tries at 98 and, if not more than the number, e.g., five (5), returns the sequence to state C again. The maximum number of tries set in decision 98 can be any number, but it is preferably set at a number, for example five (5), that is deemed to allow enough cycles or extensions of ejector rods 56, 58 to reasonably be expected to dislodge and clear the part 22 without becoming practically futile. Thus, multiple cycles of extensions and retractions of the ejector rods 56, 58 are available and used when the part 22 gets stuck, but the invention prevents unneeded repetitive cycles of the ejector rods 56, 58 when the part 22 has been dislodged and cleared from the mold.
It should be noted that although the above IR sensor system is described in combination with a skip-eject system, the IR sensor system may be utilized with any part-forming machine. It should also be noted that any number of IR sensors may be utilized.
It should be further noted that an IR emitting source, known within the art, may be utilized, wherein the source emits IR or near IR frequencies to assist in imaging the mold/part. An IR filter may also be utilized, wherein non-IR frequencies are blocked from entering the IR sensors, thus allowing IR frequencies to pass.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS33035377 Apr 196414 Feb 1967Systems Matrix IncSafety ejection control for casting machinesUS3642401 *15 Jul 196915 Feb 1972Gillette CoMolding machine monitoring systemUS423618120 Apr 197825 Nov 1980Ituo ShibataDefect detecting deviceUS4358186 *31 Dec 19799 Nov 1982Polaroid CorporationMethod and apparatus for controlling exposure by selective use of blocking visible filterUS460332912 Oct 198329 Jul 1986National Molding CorporationDevice and method for sensing the presence or absence of newly formed parts in conjunction with parts forming equipmentUS484136415 Apr 198820 Jun 1989Kawaguchi, Ltd.System for confirming the release of a molded article in an injection molding apparatus and for determining the quality of the articleUS506205220 Jun 198929 Oct 1991Cincinnati Milacron, Inc.Logic controlled plastic molding machine with programmable operator interfaceUS50620537 Nov 198929 Oct 1991Toshiba Machine Co., Ltd.Fully automatic operation system for injection molding machinesUS522319130 Jul 199129 Jun 1993Nissei Jushi Kogyo Kabushiki KaishaData processing method of injection molding machineUS524366522 Jan 19927 Sep 1993Fmc CorporationComponent surface distortion evaluation apparatus and methodUS54702187 Jul 199328 Nov 1995Wheaton Inc.Graphical interface driven injection blow molding apparatusUS556736629 Jun 199422 Oct 1996Inax CorporationMethod of finishing a green bodyUS5768138 *29 Jun 199416 Jun 1998Root Electro-Optics, Inc.Automatic tooling inspection systemUS581539724 Oct 199529 Sep 1998Fanuc Ltd.Method of analyzing factors affecting product quality and adjusting molding conditions for injection molding machineUS58913835 Jun 19966 Apr 1999Joseph; Daniel R.Method and apparatus for cooling extruded film tubesUS589859112 Aug 199627 Apr 1999Hettinga; SieboltArticle of manufacture having computer readable program code for molding an article and method of molding an article by providing computer readable program codeUS592857826 Mar 199727 Jul 1999Avalon Imaging, Inc.Skip-eject system for injection molding machinesUS59401391 Oct 199617 Aug 1999Bell Communications Research, Inc.Background extraction in a video pictureUS597857830 Jan 19972 Nov 1999Azarya; ArnonOpenbus system for control automation networksUS605117017 Feb 199718 Apr 2000Fanuc Ltd.Method of collecting molding data and obtaining molding condition for injection molding machineUS62263951 Apr 19971 May 2001Malcolm T. GillilandMethod and apparatus for determining the configuration of a workpieceUS62583031 Jun 199910 Jul 2001Kabushiki Kaisha Meiki SeisakushoApparatus and method of monitoring injection molding operation wherein sprue gate closing point of time is indicated together with displayed parameter waveforms* Cited by examinerReferenced byCiting PatentFiling datePublication dateApplicantTitleUS6810303 *18 Jun 200226 Oct 2004Ricoh Company, LtdInjection mold, a production method thereof, a production system thereof, a designing apparatus and a designing computer program thereof, an injection method, a molded component, and an optical system therewithUS703315920 May 200325 Apr 2006Avalon Vision Solutions, LlcMethod for part-forming machine having an in-mold integrated vision systemUS713431614 Oct 200414 Nov 2006Kuhman Investment Co., LlcApparatus and method for determining feedscrew and barrel wearUS716829112 Jan 200630 Jan 2007Glycon CorporationApparatus and method for determining feedscrew and barrel wearUS7175408 *11 Apr 200313 Feb 2007Nissei Plastic Industrial Co., Ltd.Mold monitoring apparatus for injection molding machineUS740977530 Aug 200612 Aug 2008Kuhman Investment Co., LlcApparatus and method for determining feedscrew and barrel wearUS748893929 Apr 200510 Feb 2009Alcoa Closure Systems International, Inc.Process monitoring of molded closuresUS758544919 Nov 20048 Sep 2009Nicol William ASensory system and method thereofUS80709939 May 20086 Dec 2011Shiloh Industries, Inc.Composite component and method of manufacturing the sameWO2006118931A2 *25 Apr 20069 Nov 2006Alcoa Closure Systems Int IncProcess monitoring of molded closures* Cited by examinerClassifications U.S. Classification425/169, 425/139, 425/137International ClassificationB22D17/22, B29C45/40, B29C45/76, B29C33/44, B22D17/32Cooperative ClassificationB29C45/7626European ClassificationB29C45/76DLegal EventsDateCodeEventDescription15 Jul 2011FPAYFee paymentYear of fee payment: 815 Jul 2011SULPSurcharge for late paymentYear of fee payment: 721 Feb 2011REMIMaintenance fee reminder mailed12 Jan 2007FPAYFee paymentYear of fee payment: 412 Jun 2002ASAssignmentOwner name: AVALON VISION SOLUTIONS, LLC, GEORGIAFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KACHNIC, EDWARD;PRYHODA, BENJAMIN;REEL/FRAME:013003/0507Effective date: 20020611Owner name: AVALON VISION SOLUTIONS, LLC 422 THORNTON ROAD, SUFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KACHNIC, EDWARD /AR;REEL/FRAME:013003/0507RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google