| 摘要 |
<p>A means of detecting faults in the grooving of a band of corrugated carton or paper, on the rear face of which, on the crests of the corrugations, a band of flat paper has been glued, includes a curved, convex, supporting surface, on which the band rests with the open corrugations upwards as it is drawn over it. There is also a source of illumination directing a beam of light which is partially obscured by one of the corrugations in the zone of the band resting on the support. The convexity of the support and the position of the light source are such that the tip of the corrugation is not masked, either by the preceding or the following corrugation. The electrical equipment includes a light sensitive arrangement for receiving the partially obscured beam and for putting out a signal representing the degree to which the beam is obscured; a means of detecting and measuring the extreme value of the measurement corresponding to the maximal obscuring caused by each corrugation; a means of comparing and indicating the relationship between the extremes of value detected and measured as detailed. Supersedes the examination of samples cut from lengths already finished. The new control is contactless and takes place during mfr. so that quality is improved, output is increased and scrap is reduced considerably. Errors due to soiling of the optical system are eliminated by a reference beam from the same source.</p> |
