BRIEF DESCRIPTION OF THE DRAWINGS
The invention will become apparent from the following accompanying drawings which illustrate, in accordance with the mandate of the patent statutes, a presently preferred embodiment.
FIG. 1 is an elevational view of a glass inspection machine for inspecting for wire edges made in accordance with the teachings of the present invention;
FIG. 2 is a view of the top surface of as bottle as imaged by the camera shown in FIG. 1;
FIG. 3 is cross sectional view through the finish portion of the glass bottle
FIG. 4 is a view similar to FIG. 2 showing the presence of a wire edge.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The inspection machine has a belt type conveyor made up of opposed pairs of belts 10 which feed a glass bottle 12 to the disclosed inspection station. Beneath the glass bottle is a light source 14 which directs light axially through the bottle. The light passes through the bore 16 of the glass bottle, through a beam splitter 18, through a field lens 20 and into a camera 22, where the light will be imaged on the camera matrix. The image will be transferred to a computer 30 where it will be evaluated and a picture of the image will be displayed on a screen 32. A vertically oriented LED panel 26 directs light horizontally to the beam splitter 18 which reflects a portion of the light vertically, axially, downwardly at the top (sealing surface) 28 of the glass bottle.
FIG. 2 is an in image of the top of the glass bottle when the LED light source is turned off. The vertical hole in the finish of the glass bottle appears bright (white) while the rest of the image is black.
FIG. 3 shows the top of a bottle which has a flat sealing surface 24 and a very small inside step 26 which is slightly inclined (For purposes of clarity, this step is shown much larger than it would be). Projecting vertically upwardly is a “wire edge” 40 which can extend along a portion of the interior edge of the step. A wire edge is very undesirable since it may break off.
FIG. 4 shows an image of the top of the glass bottle shown in FIG. 3 with the bottom 14 and LED 26 light sources “on”. The hole in the finish continues to be bright or white. Enough light reflects upwardly from the sealing surface to make the sealing surface to appear gray. The annular Black area 42 between the Gray and Bright areas defines the annular step 26 with the wire edge 40 appearing Gray. The wire edge is highlighted and the lighting defines a well-defined annular black ring 42 in which a wire edge will be located.