Abstract: The apparatus is used for detecting the proper conductivity of a conductive film enclosed within a nonconductive substrate or envelope such as a fluorescent lamp without requiring physical contact with the fluorescent lamp. The conductive film detector comprises a capactive proximity switch mounted close to but spaced from the lamp as the lamp passes the inspection station. At the inspection station there is also provided a feeler switch for sensing lamp presence and a cam switch for inspection initiation when the lamp is instantaneously properly positioned. A control unit powers the capacitive proximity switch and receives the proximity switch output to control a lamp rejection mechanism for rejecting lamps having resistance that is too high. The set up procedure involved adjustment of the capacitive proximity switch sensitivity by using test lamps of alternately acceptable resistance and unacceptable resistance, along with adjustment of lamp-to-proximity switch spacing.

Abstract: The apparatus is used for detecting the proper conductivity of a conductive film enclosed within a nonconductive substrate or envelope such as a fluorescent lamp without requiring physical contact with the fluorescent lamp. The conductive film detector comprises a capacitive proximity switch mounted close to but spaced from the lamp as the lamp passes the inspection station. At the inspection station there is also provided a feeler switch for sensing lamp presence and a cam switch for inspection initiation when the lamp is instantaneously properly positioned. A control unit powers the capacitive proximity switch and receives the proximity switch output to control a lamp rejection mechanism for rejecting lamps having resistance that is too high. The set up procedure involved adjustment of the capacitive proximity switch sensitivity by using test lamps of alternately acceptable resistance and unacceptable resistance, along with adjustment of lamp-to-proximity switch spacing.