| 摘要 |
A label inspection system automatically inspects print on labels carried seriatim on a web. The system comprises a photoelectric sensing system including a light inspection sensor sensing reflected light and an electrical control circuit providing an output at a select first or second electrical state dependent upon sensed reflected light being above or below a select level. The sensor is mounted at a select transverse position in a path of movement of the web to sense reflected light along a select longitudinal path of the web, the select longitudinal path including a portion of the labels carried on the web intended to have print, the print acting to minimize reflected light. A detect sensor sense proximity of the inspection sensor relative to a select longitudinal portion of each successive label and provide an enable signal relative thereto. A control circuit is operatively coupled to the sensing system and the detect sensor including a logic circuit for analyzing the sensing system output only when the enable signal is received, and an output circuit for indicating the presence or absence of print on each label dependent upon if reflected light is above or below the select level when the logic circuit is analyzing the sensing system output.
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