Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems
Patent
1985-11-06
1987-07-28
LaRoche, Eugene R.
Radiant energy
Photocells; circuits and apparatus
Photocell controls its own optical systems
250557, 250561, G01N 2186
Patent
active
046833803
ABSTRACT:
A photoelectric perforation sensor for accurately detecting a perforation in a moving web. The sensor comprises two large photodiodes in a bi-cell configuration. The photodiodes lie in the direction of web travel. As the perforation begins to pass between an LED source and the bi-cell, light from the LED illuminates one photodiode but not the other. As the perforation becomes centered over the photodiodes, both photodiodes receive equal amounts of illumination and a signal is generated indicating location of the perforation. The circuit for detecting the perforation includes a first comparator circuit for comparing the output of the photodiodes with each other, a second comparator circuit for comparing the sum of the two outputs with a peak detector to arm the first comparator circuit and to prevent false triggering, and a third comparator circuit which compares the output of the peak detector with a reference voltage to shut down the system when an insufficient amount of light is being received by the photodiodes.
REFERENCES:
patent: 3473035 (1969-10-01), Gardner et al.
patent: 3936650 (1976-02-01), Stenudd
patent: 3950652 (1976-04-01), Yamashita
patent: 4025186 (1977-05-01), Hunt, Jr. et al.
patent: 4118129 (1978-10-01), Grundherr
patent: 4142105 (1979-02-01), Erdmann
patent: 4207473 (1980-06-01), Nakatani et al.
patent: 4569584 (1986-02-01), St. John et al.
Electronics, Apr. 15, 1960, M. P. MacMartin, "Sensitive Flaw Detector Solves Noise Problems", pp. 64-66.
Lambeg Industrial Research Association, Research Disclosure, No. 17322, Sep. 1978, pp. 40-43.
Pearce Phillip W.
Shipkowski James P.
Eastman Kodak Company
LaRoche Eugene R.
Mis David
Rushefsky Norman
LandOfFree
Apparatus and method for detecting a perforation on a web does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for detecting a perforation on a web, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for detecting a perforation on a web will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2036067