There has been proposed in prior art an identification device which identifies the denomination of a bank bill from the numerical figures thereon; however, it is of a simple type which recognizes the numerical figures by the variation of the light level reflected from the portion of a note having such numerical figures printed thereon by means of a sensor to thereby identify the denomination thereof. The device is detrimental in that a note is erroneously identified due to stains on the note. It is not quite practically usable as it is necessary to convey a note with one of the edges thereof placed under a strict control so that the numerical portion thereof should be surely passed through the sensoring position. According to this invention, one-dimensional image sensors are provided over the numerical portion on both sides of a note, signals output from the image sensors in time serial are encoded and characteristic signals for the numerical figures on the note are formed. The characteristic signals are stored for each scanning of the image sensors, thus stored data is computed to be compared with the reference data which has been stored corresponding to the denomination of notes, thereby identifying the denomination of the note.

A bill counting machine includes a holder for supporting bills thereon and suction heads for turning over the bills, one at a time, to count them. A projector is provided for emitting a ray of light onto the surface of each bill. A receptor is provided for detecting a ray of light reflected from the surface of the bill and for rectilinearly reading the surface pattern of the bill. The rectilinear reading allow judgments as to the denomination and obverse/reverse side of the bills.

Provided adjacent to the passageway for the bill 14 is an image sensor 17 which converts symbols printed on the bill 14 into electric signals during movement of the bill 14 along a passageway by a conveyer 15. Printer 19 records on printing paper the symbols based on output signals of the image sensor 17. Thus, the symbols printed on the documents may automatically be recorded.

A monitoring system, particularly for use with document sorting apparatus, comprises a sensor assembly including a sensor for sensing a respective characteristic of an article and for generating a corresponding first output signal, and a detector controller for applying at least one of a predetermined set of algorithms to the first output signal from the sensor, in conjunction with data supplied to the detector controller, to generate one or more second output signals. A detector processor common to each of the sensor assemblies supplies the data and algorithm selection information to the detector controllers to control which of the set of algorithms is applied by the detector controller and to generate in response to the or each second output signal and reference data a third output signal representative of the characteristic of the article being monitored.

A currency validator for testing both the magnetic and electrically conductive properties of a currency note in which core legs of magnetic and conductive material form spaced first and second gaps. Windings carried by the legs produce signals indicative of the magnetic property of a note moving across the first gap. A detector connected across the second gap indicates the presence of conductive material bridging the first gap.