Lid placement and seating detector

Abstract

An inspection station for checking the correct placement of a lid on a filled plastic container that is traveling on a conveyor that includes: a detector plate assembly ( 16 ) that has a flat surface ( 32 ) and an inclined surface ( 44 ); a support assembly ( 18 ); a mounting assembly ( 22 ) for attaching the detector plate assembly ( 16 ) to the support assembly ( 18 ) for holding the flat surface ( 32 ) in a predetermined parallel relationship with a top or conveying surface ( 30 ) of the conveyor ( 12 ) while simultaneously allowing vertical displacement thereof; a first sensor ( 54 ) for detecting the presence of a plastic container ( 20 ) to be checked or inspected; a second sensor ( 56 ) for sending a signal when the detector plate is within a selected range of vertical displacement. In operation the plastic container traveling horizontally on the conveyor first contacts the inclined surface thereby vertically displacing the detector plate assembly ( 16 ) sufficiently for subsequently allowing the flat surface ( 32 ) to contact a top surface of the plastic container for allowing the second sensor ( 56 ) to cooperate with a notched bar ( 58 ) to determine whether the vertical displacement is outside of the selected range.

What is claimed is:  
     
         1 . An apparatus for checking the correct placement of a lid on a filled plastic container traveling on a conveyor including: 
 a). a detector plate assembly including a flat surface and an inclined surface;    b) support assembly;    c) a means for mounting the detector plate assembly to the support assembly whereby the flat surface of the detector plate being held in a predetermined parallel relationship with top surface of the conveyor while simultaneously allowing vertical displacement thereof;    d) a first sensor for detecting the presence of a plastic container to be checked;    d) a second sensor for sending a signal when the detector plate is within a selected range of vertical displacement; and    wherein the plastic container traveling horizontally on the conveyor first contacts the inclined surface thereby vertically displacing the detector plate assembly sufficiently for subsequently allowing the flat surface to contact a top surface of the plastic container wherein the second sensor determines and sends a signal whether the vertical displacement is outside the selected range.    
     
     
         2 . An apparatus as recited in  claim 1  wherein the area of the flat surface momentarily overlaps at least 80 percent of an area within a peripheral outline of the top surface of the plastic container as and when the plastic container is traveling horizontally on the conveyor.  
     
     
         3 . An apparatus as recited in  claim 1  wherein the means for mounting the detector plate to the support assembly includes a pair of elongated shafts that are selectively spaced in a predetermined parallel relationship on the support assembly.  
     
     
         4 . An apparatus as recited in  claim 2  wherein the means for mounting the detector plate to the support assembly includes a pair of elongated shafts that are selectively spaced in a predetermined parallel relationship on the support assembly.  
     
     
         5 . An apparatus as recited in  claim 3  wherein the means for mounting the detector plate to the support assembly further includes a pair of ball bushing assemblies that are selectively spaced in a predetermined parallel relationship on the detector plate assembly for vertical movement on the pair of elongated shafts.  
     
     
         6 . An apparatus as recited in  claim 4  wherein the means for mounting the detector plate to the support assembly further includes a pair of ball bushing assemblies that are selectively spaced in a predetermined parallel relationship on the detector plate assembly for vertical movement on the pair of elongated shafts.  
     
     
         7 . An apparatus as recited in  claim 1  that further includes at least one adjusting assembly for selectively aligning the flat surface with the top surface of the plastic container.  
     
     
         8 . An apparatus as recited in  claim 2  that further includes at least one adjusting assembly for selectively aligning the flat surface with the top surface of the plastic container.  
     
     
         9 . An apparatus as recited in  claim 3  that further includes a least one adjusting assembly for selectively aligning the flat surface with the top surface of the plastic container.  
     
     
         10 . An apparatus as recited in  claim 4  that further includes a least one adjusting assembly for selectively aligning the flat surface with the top surface of the plastic container.  
     
     
         11 . An apparatus as recited in  claim 5  that further includes a least one adjusting assembly for selectively aligning the flat surface with the top surface of the plastic container.  
     
     
         12 . An apparatus as recited in  claim 6  that further includes a least one adjusting assembly for selectively aligning the flat surface with the top surface of the plastic container.  
     
     
         13 . An apparatus as recited in  claim 1  wherein the second sensor is mounted on an adjusting assembly, the adjusting assembly being adapted for selectively aligning the flat surface with the top surface of the plastic container for sending the signal.  
     
     
         14 . An apparatus as recited in  claim 2  wherein the second sensor is mounted on an adjusting assembly, the adjusting assembly being adapted for selectively aligning the flat surface with the top surface of the plastic container for sending the signal.  
     
     
         15 . An apparatus as recited in  claim 3  wherein the second sensor is mounted on an adjusting assembly, the adjusting assembly being adapted for selectively aligning the flat surface with the top surface of the plastic container for sending the signal.  
     
     
         16 . An apparatus as recited in  claim 5  wherein the second sensor is mounted on an adjusting assembly, the adjusting assembly being adapted for selectively aligning the flat surface with the top surface of the plastic container for sending the signal.  
     
     
         17 . An apparatus as recited in  claim 1  wherein the second sensor is a proximity switch that detects a notched portion of the detector plate assembly. for sending the signal.  
     
     
         18 . An apparatus as recited in  claim 2  wherein the second sensor is a proximity switch that detects a notched portion of the detector plate assembly. for sending the signal.  
     
     
         19 . An apparatus as recited in  claim 3  wherein the second sensor is a proximity switch that detects a notched portion of the detector plate assembly. for sending the signal.  
     
     
         20 . An apparatus as recited in  claim 16  wherein the second sensor is a proximity switch that detects a notched portion of the detector plate assembly. for sending the signal.