Monitor system for coating apparatus

Abstract

A spray monitoring device analyzes images obtained from a beam passing through a spray pattern applying a spray to a substrate, and identifies discontinuities in the image as indicative of a discontinuity in a spray pattern. The spray pattern is produced by a plurality of nozzles spaced apart across the substrate for applying a suitable coating thereto. The beam is produced by a laser, that preferably has a collimator for distributing the beam intensity. The beam is imaged by a camera that provides a constant image to a computers where the scattering of beam light by the spray pattern is processed by image processing software and optionally provided to a user interface for analysis. Discontinuities detected by the user or software indicate faulty spray nozzles and may trigger remedial action.

1 - 13 . (canceled) 
     
     
         14 . A system for monitoring the application of coating to a surface of a substrate, the coating being applied as a spray from a plurality of nozzles spaced apart along at least one dimension of the substrate, the system comprising: a coherent radiation source arranged to direct a beam of coherent radiation through said spray; an imaging device for obtaining an image of said beam as it propagates through said spray, and a computing device having a processor to receive an input from said imaging device and process said image in order to determine variations in a characteristic indicative of the presence of said spray. 
     
     
         15 . A system according to  claim 14  further comprising an interface connected to said computing device, said interface permitting a user to interact with said image. 
     
     
         16 . A system according to  claim 14  wherein said processing identifies discontinuities in said characteristic. 
     
     
         17 . A system according to  claim 16  wherein said processing determines the lack of continuity of areas of said image in excess of a predetermined value, which are utilized to identify discontinuities in said characteristic. 
     
     
         18 . A system according to  claim 16  wherein said processing identifies the scattering of said radiation by said spray of coating, and isolates a region with scattering below a predetermined threshold to identify discontinuities in said characteristic. 
     
     
         19 . A system according to  claim 14  wherein said coherent radiation source is a laser beam generated by a laser. 
     
     
         20 . A system according to  claim 19  wherein said laser further comprises a collimator to produce a non-Gaussian, substantially uniform intensity line from said laser beam. 
     
     
         21 . A system according to  claim 14  wherein said imaging device is a camera. 
     
     
         22 . A system according to  claim 21  wherein said camera is a smart camera and said computing device and said processor are operated by said smart camera. 
     
     
         23 . A system according to  claim 14  wherein said imaging device is positioned with its field of view along an intended path of said substrate. 
     
     
         24 . A system according to  claim 14  wherein said imaging device is disposed to one side of said substrate with its field of view along an angle to an intended path of said substrate. 
     
     
         25 . A system according to  claim 14  further comprising a second coherent radiation source and a second imaging device, both of which are all arranged to monitor the application of a coating to a second surface of said substrate. 
     
     
         26 . A system according to  claim 14  wherein said plurality of nozzles are spaced along a plurality of sprayheads to produce a plurality of sprays, said system further comprises a coherent radiation source for each of said sprays to direct a beam of coherent radiation through each of said sprays, and wherein said imaging device is arranged to capture at least two of said beams as they propagate through respective sprays in the same image. 
     
     
         27 . A system according to  claim 26  wherein at least two of said plurality sprayheads are offset in a vertical direction with respect to each other and said imaging device is positioned with its field of view substantially parallel to an intended path of said substrate. 
     
     
         28 . A system according to  claim 26  wherein said plurality of sprayheads are arranged vertically coincident with each other and said imaging device is offset vertically therefrom. 
     
     
         29 . An apparatus for applying coating to a substrate, the apparatus comprising: a coating station having a feeder for continuously feeding said substrate through said apparatus; at least one spray head connected to said coating station and positioned a predetermined distance from said substrate, said sprayhead having a plurality of nozzles, said nozzles being connected to a source of coating to enable coating to be fed through said nozzles to produce a spray of coating, said spray of coating being applied to a surface of said substrate; at least one coherent radiation source arranged to direct a beam of coherent radiation through said spray as said spray is applied to said substrate; an imaging device for obtaining an image of said beam as it propagates through said spray; and a computing device having a processor for processing said image to determine variations in a characteristic indicative of the presence of said spray. 
     
     
         30 . An apparatus according to  claim 29  further comprising an interface connected to said computing device, said interface permitting a user to interact with said image. 
     
     
         31 . An apparatus according to  claim 29  having a pair of sprayheads each positioned on respective sides of said substrate, to spray at oppositely directed surfaces of said substrate; a pair of coherent radiation sources each arranged to direct respective beams of coherent radiation through respective sprays of respective sprayheads; and a pair of imaging devices, each imaging device being positioned to obtain respective images of respective beams as they propagate through respective sprays; wherein said processor processes a pair of images to determine variations in a characteristic indicative of the presence of respective sprays applied to each surface. 
     
     
         32 . An apparatus according to  claim 29  wherein said coherent radiation source is a laser beam generated by a laser. 
     
     
         33 . An apparatus according to  claim 32  wherein said laser further comprises a collimator, said collimator altering said laser beam to produce a non-Gaussian, substantially uniform intensity line. 
     
     
         34 . An apparatus according to  claim 29  wherein said imaging device is a camera. 
     
     
         35 . An apparatus according to  claim 34  wherein said camera is a smart camera and said computing device and said processor are operated by said smart camera. 
     
     
         36 . An apparatus according to  claim 29  wherein said imaging device is positioned with it field of view along the path of travel of said substrate. 
     
     
         37 . An apparatus according to  claim 29  wherein said imaging device is disposed to one side of said substrate with its field of view along a angle to the path of travel of said substrate. 
     
     
         38 . An apparatus according to  claim 29  wherein said plurality of nozzles are spaced along a plurality of sprayheads to produce a plurality of sprays, said system further comprises a coherent radiation source for each of said sprays to direct a beam of coherent radiation through each of said sprays, and wherein said imaging device is arranged to capture at least two of said beams as they propagate through respective sprays in the same image. 
     
     
         39 . An apparatus according to  claim 38  wherein at least two of said plurality sprayheads are offset in a vertical direction with respect to each other and said imaging device is positioned with its field of view substantially parallel to an intended path of said substrate. 
     
     
         40 . An apparatus according to  claim 38  wherein said plurality of sprayheads are arranged vertically coincident with each other and said imaging device is offset vertically therefrom.