Radiant energy – Photocells; circuits and apparatus – Optical or pre-photocell system
Patent
1993-06-21
1995-05-09
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Optical or pre-photocell system
250214B, 356429, G01N 2186
Patent
active
054142695
ABSTRACT:
A print paper detecting circuit for installation on a printer, to detect whether a print paper is supplied at a predetermined position along a paper path by using an optical sensor composed of a light emitting diode and phototransistor. The circuit detects the existence of the print paper according to the detection of light which is emitted from the light emitting diode, which is reflected from the print paper, and which arrives at the phototransistor. According to one embodiment, circuit has a current amplifier and a gain reducing circuit. The current amplifier feeds a pulse current which is greater than the normal constant current to the light emitting diode while the gain reducing circuit reduces the output of the output voltage. From the phototransistor during the time that the pulse current is supplied with this circuit arrangement any external light entering the printer does not affect the detection of the presence of the printer paper since the quantity of the light from the light emitting diode is greater than the quantity of the external light.
REFERENCES:
patent: 4372672 (1983-02-01), Pries
patent: 4737649 (1988-04-01), Naruse
patent: 4778296 (1988-10-01), Takahashi
patent: 4851689 (1989-07-01), Hasegawa
patent: 4983854 (1991-01-01), Mizuno et al.
patent: 5004901 (1991-04-01), Yoshimoto et al.
patent: 5008532 (1991-04-01), Ono et al.
patent: 5084627 (1992-01-01), Ucki et al.
patent: 5117119 (1992-05-01), Schubert et al.
patent: 5289011 (1994-02-01), Wong et al.
J. C. McKenney "Printer Paper Top of Form and End of Form Sensor", IBM Technical Disclosure Bulletin, vol. 27, No. 28, Sep. 1984, pp. 2535-2538.
"Mechanism on a Serial Printer", IBM Technical Bulletin, vol. 30, No. 4, Sep. 1987, pp. 1894-1895.
Le Que T.
Nelms David C.
OKI Electric Industry Co., Ltd.
LandOfFree
Circuit for detecting a paper at a desired position along a pape does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Circuit for detecting a paper at a desired position along a pape, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Circuit for detecting a paper at a desired position along a pape will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1707982