This technology is particularly applicable to banknote validation of coin changers and vending machines. This device discriminates transparent tape or opaque tape affixed on banknote by infrared (IR) LEDs (Light Emitting Diodes) and by optical IR sensors to make possible to produce more precise validation device with compact size at reduced production cost.

Background Art Banknotes with either adhesive transparent tapes or opaque tapes make jams very often in validation process for banknotes for coin changers and vending machines etc.

Therefore it is definitely needed to discriminate transparent taped or opaque taped banknotes from the banknotes without it.

Therefore, some developments have been made to detect taped banknotes either by measuring its thickness or by pattern recognition technology using optical sensors.

The conventional taped banknote detection devices adopting pattern recognition technology had been effective to some extent to detect opaque taped banknotes, however, it is not so much effective to detect transparent taped banknotes because they reflect very little amount of light fallen on banknote and reflect too little amount of light to be

measured by optical sensor.

On the other hand, the other taped banknote detection devices adopting very delicate thickness measuring sensors, should be produced with utmost care in production processes to avoid malfunction. On top of this, thickness measurement sensors are very expensive and eventually they increase production cost.

Disclosure of Invention The present invention is designed to solve above problems by employing low priced IR LEDs and IR sensors, which are installed with inclination to measure reflected amount of IR ray from banknotes to discriminate taped banknotes. With this device, more precise discrimination is possible by the optical IR sensors at lower production cost.

Brief Description of Drawings Fig 1 shows the side view of taped banknote detector with IR LEDs and IR sensors according to the present invention; Fig 2 shows the ground view of taped banknote detector with IR LEDs and IR sensors according to the present invention; Fig 3 is the side view of taped banknote detector according to the present invention showing interactive processes in operation; Fig 4 is the brief diagram showing taped banknote detecting processes using taped

banknote detector according to the present invention; and Fig 5 is the flow chart showing overall taped banknote detecting processes using taped banknote detector according to the present invention.

*** Explanation of Reference numerals designating the Major Element of the Drawings*** 1. 1'PCB (Printed Circuit Board) 2 IR LEDs (Light Emitting Diode) 3 Optical IR sensors 4 Hole in PCB for transmitting IR ray 5 Inlet of banknote 6 Outlet of banknote 7: Banknote Best Mode for Carrying Out the Invention Now, preferred embodiments of the present invention will be described in detail with reference to the annexed drawings.

Fig 1 shows the side view of taped banknote detector with IR LEDs and IR sensors according to the present invention, Fig 2 shows the ground view of taped banknote detector with IR LEDs and IR sensors according to the present invention, Fig 3 is the side view of taped banknote detector according to the present invention showing interactive processes

in operation, Fig 4 is the brief diagram showing taped banknote detecting processes using taped banknote detector according to the present invention; and Fig 5 is the flow chart showing overall taped banknote detecting processes using taped banknote detector according to the present invention.

The transparent taped banknote detector according to the present invention comprising: sets of tape detecting unit comprised of one or more IR LEDs emitting IR ray (2) and optical IR sensors (3) detecting IR ray reflected from banknote arranged in inclined angle and mounted on both sides of PCBs (1) (1') having several holes (4) through which transmittance of IR ray is made; and a control unit carrying out the comparison of the amount of the IR ray detected by IR sensors (3) to the stored data of authentic banknote and discriminating taped banknote from normal banknote, and transmitting the result of comparison to display unit and communication unit to display the result and either to validate or reject the banknote.

Now, the function of taped banknote detector according to the present invention is described below.

To operate this taped banknote detector, power supply should be made in order to activate several IR LEDs (2), optical IR sensors (3), and the other moving parts as well (S 10).

As shown in Fig 3, while a banknote (7) is incoming through inlet gate (not shown) of the detector housing (not shown) and passes through the inlet of banknote (5) and travels to

outlet of banknote (6) between PCBs (1) (1'), IR ray from IR LEDs (2) falls on the banknote (7) through the holes (4) in the PCBs (1) (1') and the amount of reflected IR ray from the banknote (7) is detected by optical IR sensor (3).

The optical IR sensor (3) transmits the measured data to the control unit (CPU) (S20), and the CPU compares it with the stored data of authentic banknote. (S30) and determines whether the measured data is smaller than the stored set-up data (S40) or not.

If the amount of measured IR ray is smaller than the stored set-up data, the CPU compares the other measured data with stored set-up data to validate the banknote (S50).

And in case of acceptance, CPU transmits a signal to display allowing further validation of new banknote (S60).

And in case the amount of measured IR ray is bigger than the stored set-up data, CPU transmits a signal to reject the banknote (S70).

It is possible because either transparent taped banknotes or opaque taped banknotes reflect almost all IR ray emitted from IR LEDs and the amount of IR rays detected by optical IR sensor is much bigger than the authentic banknotes do.

And we found that the best result comes when within 30 degree mounting angle between IR LEDs (2) and IR sensors (3) is made.

Accordingly, by employing several relatively low priced IR LEDs (2) and optical IR sensors (3), we can discriminate either transparent taped or opaque taped banknotes (7) from authentic banknotes more precisely with compact system and at lower production cost.

Industrial Applicability As explained above, this invention adopts tilted mounted relatively chip IR LEDs and IR sensors to measure the amount of reflected IR and consequently discriminate taped banknotes more precisely at lower production cost.