초록 ▼

A method of inspecting wall thickness of blow-molded plastic containers includes providing a blow-molder having a plurality of molds and a plurality of associated spindles. The containers are inspected by impinging infrared light thereon and detecting the portion of the infrared light that passes th

A method of inspecting wall thickness of blow-molded plastic containers includes providing a blow-molder having a plurality of molds and a plurality of associated spindles. The containers are inspected by impinging infrared light thereon and detecting the portion of the infrared light that passes through the container and converting the same into corresponding electrical signals which are delivered to a microprocessor. The microprocessor compares the electrical signals with stored information regarding desired wall thickness of the container and emits output thickness information. The microprocessor receives signals from sensors associated with the blow-molder relating to the position of the molds, the identity of the molds and the identity of the spindles in order that the wall thickness information that is determined by inspection can be associated with specific molds and spindles. The wall thickness information may be averaged over a period of time or a number of containers. The information may be visually displayed so as to provide feedback regarding the inspection process. In a preferred embodiment wall thickness measurements are taken at several vertically spaced positions simultaneously. Corresponding apparatus is provided.

대표청구항 ▼

1. A method of inspecting wall thickness of blow-molded plastic containers comprisingproviding a plastic container blow-molder having a plurality of molds and a plurality of spindles, inspecting said container by impinging infrared light thereon from the exterior thereof and detecting the portion of

1. A method of inspecting wall thickness of blow-molded plastic containers comprisingproviding a plastic container blow-molder having a plurality of molds and a plurality of spindles, inspecting said container by impinging infrared light thereon from the exterior thereof and detecting the portion of said infrared light that passes through two walls of said container, converting said detected light into corresponding electrical signals which are delivered to a microprocessor, comparing in said microprocessor said electrical signals with stored data regarding desired wall thickness and emitting output thickness information regarding said container wall thickness, and delivering to said microprocessor signals received from sensors associated with said blow-molder relating to said mold and said spindle involved in making the container being inspected. 2. The method of claim 1, includingsaid microprocessor output thickness information having identification of said mold and said spindle employed in making said container and employing two distinct infrared wavelengths in said inspection method. 3. The method of claim 2, includingdelivering to said microprocessor signals from a sensor associated with said blow molder for determining the position of said molds and said spindles. 4. The method of claim 2, includingautomatically rejecting any container which does not pass said inspection by separating the same from adjacent non-rejected containers. 5. The method of claim 2, includingsensing within said blow-molder the position of said molds. 6. The method of claim 5, includingdelivering said sensor obtained mold position information to said microprocessor. 7. The method of claim 2, includingsaid sensors associated with said blow-molder being disposed within said blow-molder. 8. The method of claim 2, includingemploying said output thickness information to adjust operation of said blow-molder when undesired thickness variations occur. 9. The method of claim 2, includingemploying said output thickness information to initiate an alarm when predetermined conditions exist. 10. The method of claim 2, includinginspecting a plurality of vertically spaced portions of said container substantially simultaneously. 11. The method of claim 10, includingsaid microprocessor providing output thickness information for each said vertically disposed portion. 12. The method of claim 11, includingemploying a plurality of detectors in effecting said detecting, and employing a plurality of infrared light sources each operatively associated with a said detector. 13. A method of inspecting wall thickness of blow-molded plastic containers comprisingproviding a plastic container blow-molder having a plurality of molds and plurality of spindles, inspecting said container by impinging infrared light thereon and detecting the portion of said infrared light that passes through said container, converting said detected light into corresponding electrical signals which are delivered to a microprocessor, comparing in said microprocessor said electrical signals with stored data regarding desired wall thickness and emitting output thickness information regarding said container wall thickness, delivering to said microprocessor signals received from sensors associated with said blow-molder relating to said mold and said spindle involved in making the container being inspected, and employing two distinct infrared wavelengths in said inspection method. 14. The method of claim 12, includingproviding a reject station for physically removing rejected containers, and effecting said inspection after said container emerges from said blow-molder but prior to the container's reaching said rejection station. 15. The method of claim 13, includingeffecting said inspection on-line. 16. The method of claim 13, includingprior to initiating an inspection cycle confirming the presence of a container at the desired inspection position. 17. The method of claim 13, includingemploying a first said infrared wavelength which corresponds to an absorption band of said plastic, and employing a second said infrared wavelength which is only slightly absorbed by said plastic. 18. A method of inspecting wall thickness of blow-molded plastic containers comprisingproviding a plastic container blow-molder having a plurality of molds and a plurality of spindles, inspecting said container by impinging infrared light thereon and detecting the portion of said infrared light that passes through container, converting said detected light into corresponding electrical signals which are delivered to a microprocessor, comparing in said microprocessor said electrical signals with stored data regarding desired wall thickness and emitting output thickness information regarding said container wall thickness, delivering to said microprocessor signals received from sensors associated with said blow-molder relating to said mold and said spindle involved in making the container being inspected, inspecting a plurality of vertically spaced portions of said container substantially simultaneously, said microprocessor providing output thickness information for each said vertically disposed portion, and visually displaying at least a portion of said microprocessor emitted output thickness information. 19. The method of claim 18, includingin said output thickness information associating said container thickness information with identification of the mold and the spindle involved in the manufacture of said container. 20. The method of claim 19, includingin said output thickness information a thickness averaged for a time period. 21. The method of claim 20, includingupdating said output thickness information after each inspection of a said container. 22. The method of claim 20, includingsaid time period being about 30 seconds to 10 minutes. 23. The method of claim 19, includingincluding in said output thickness information a thickness averaged for a number of containers. 24. The method of claim 23, includingsaid number of containers being about 2 to 2500. 25. Apparatus for inspecting wall thickness of blow-molded plastic containers comprisinga blow-molder having a plurality of molds and a plurality of spindles, at least one source of infrared light for impinging said light on said container from the exterior thereof, at least one infrared detector for receiving infrared light passing through two walls of said container and converting the same into corresponding electrical signals, a microprocessor for receiving said electrical signals and comparing the same with stored data and determining the wall thickness of said container and whether it is within desired limits and emitting output thickness information, and blow-molder sensors preferably associated with said blow-molder to identify said molds and spindles and provide input to said microprocessor from which it can associate said container thickness information with the mold and spindle which made said container. 26. The apparatus of claim 25, includinga machine sensor associated with said blow-molder for providing information regarding the positions of said mold and delivering a machine position signal to said microprocessor, and said source of infrared light emitting infrared of two different wave lengths. 27. The apparatus of claim 26, includinga container position sensor for confirming that a container is present at the desired inspection position and emitting a signal to said microprocessor. 28. The apparatus of claim 26, includingsaid microprocessor thickness information including average container wall thickness over a predetermined time period. 29. The apparatus of claim 28, includingsaid predetermined time period being about 30 seconds to 10 minutes. 30. The apparatus of claim 25, includinga plurality of said infrared light sensors and infrared detectors to permit inspection of said wall thickness at a plurality of vertically spaced locations, a visual display unit for receiving output thickness information from said microprocessor and displaying the same, and said visual display unit providing separate information for each said mold and each said spindle. 31. The apparatus of claim 30, includingsaid visual display unit displaying information regarding average wall thickness over a period of time. 32. The apparatus of claim 30, includingreject apparatus for removing a container if said microprocessor determines that the wall thickness is not within a desired range. 33. The apparatus of claim 30, includingsaid microprocessor being structured to update said thickness information after each inspection of a said container. 34. The apparatus of claim 30, includingsaid microprocessor thickness information being an average thickness, and said visual display unit displaying said average thickness as related to specific said molds and spindles. 35. Apparatus for inspecting wall thickness of blow-molded plastic containers comprisinga blow-molder having a plurality of molds and a plurality of spindles, at least one source of infrared light for impinging said light on said container, at least one infrared detector for receiving infrared light passing through said container and converting the same into corresponding electrical signals, a microprocessor for receiving said electrical signals and comparing the same with stored data and determining the wall thickness of said container and whether it is within desired limits and emitting output thickness information, blow-molder sensors preferably associated with said blow-molder to identify said molds and spindles and provide input to said microprocessor from which it can associate said container thickness information with the mold and spindle which made said container, and said source of infrared light emitting infrared light of two different wave lengths. 36. The apparatus of claim 35, includingsaid apparatus being positioned for on-line inspection of said containers. 37. The apparatus of claim 35, includingsaid microprocessor thickness information including average container wall thickness for a number of containers. 38. The apparatus of claim 37, includingsaid number of containers being about 2 to 2500. 39. The apparatus of claim 34, includingsaid microprocessor average thickness information being for a specific period of time. 40. The apparatus of claim 34, includingsaid microprocessor average thickness information being for a specific number of containers.