US 4,046,469 A · Photocopy machine having photoelectric paper cut-off sensor

Abstract

A reciprocating carrier-type photocopy machine having a photoelectric sensor for controlling a copy paper cut-off knife, to conform automatically the size of the copy paper to the size of the original document. A light emitter and photoelectric sensor are mounted beneath a glass platen over which a carrier, which contains the original document, moves for exposing the document to the reproducing mechanism contained beneath. An elongated rectangular mirror is mounted on the bottom surface of the carrier lid for reflecting the emitted light back to the sensor. The original document, when placed in the carrier, blocks the emitted light from being reflected from the mirror to the sensor until the trailing edge of the document passes the emitted light. The reflected light, upon passage of the document, then actuates the photoelectric sensor, which in turn actuates a solenoid of a copy paper cut-off knife to sever the copy paper from its supply roll. The emitted light preferably is infrared and is modulated at a predetermined frequency to which the sensor is tuned to prevent premature actuation of the cut-off knife by an extraneous light source.

Claims15

Dependent claims

A photocopy machine of the type having an original document carrier mounted for reciprocating movement on the top of a housing for moving the document across an external exposure station for reproduction of the document on a traveling web of copy paper fed from a supply roll of said paper located within the housing, said carrier having a lid and a transparent platen between which the document is placed;

knife means for cutting the traveling web from the supply roll;
and means controlling the reciprocating movement of the carrier and for controlling operation of the knife means;
the improvement including:
a. photoelectric means mounted beneath the transparent platen of the carrier rearwardly of the external exposure station and having light emitting means and light sensing means;
b. a reflecting surface provided on the bottom of the carrier lid in alignment with the photoelectric means and adapted to pass over said photoelectric means upon forward movement of the carrier;
c. electrical circuit means operatively connecting the photoelectric means with the knife means operating control means;
and
d. the light emitting means adapted to project a beam of light upwardly through the transparent platen of the carrier toward the carrier lid, with said light beam being blocked by a document in the carrier until passage of the trailing end of the document whereupon said light beam is reflected by the reflective surface of the lid and sensed by the light sensing means to actuate the knife means through the electrical circuit means to cut the traveling copy paper web to a length in direct relationship to the length of the original document.

5 more elements

A photoelectric paper cut-off sensor for a photocopy machine of the type having an original document carrier mounted for reciprocating movement on the top of a housing for moving the document across an external exposure station for reproduction of the document on a traveling web of copy paper supplied from a roll of said paper located within the housing, and means for severing the traveling web of copy paper from the roll, wherein the improvement includes:

a. light emitting means and light sensing means mounted in close priximity to each other beneath the document carrier rearwardly of the external exposure station;
b. reflecting means mounted above the light emitting means and light sensing means, with a document being movable by the carrier between said light emitting and sensing means and the reflecting means;
c. the light emitting means being adapted to project a light beam upwardly toward the reflecting means, with the light sensing means sensing said light beam when reflected by the reflecting means;
and
d. means operatively connected between the light sensing means and copy paper severing means for actuating said severing means upon the light sensing means sensing the reflected light beam, whereby a document in the carrier blocks the light beam from the reflecting means until passage of the document trailing edge, whereupon the light beam is reflected by the reflecting means to the light sensing means to actuate the copy paper severing means.

2 more elements

Dependencies are inferred from the claim text.

Photocopy machine having photoelectric paper cut-off sensor

Life of this patent

Photocopy machine having photoelectric paper cut-off sensor

Life of this patent

Abstract

Claims15