Patent Application
20130088708
1. Field of the Invention
The present invention relates to a detecting apparatus, in particularly to an apparatus for optically detecting a foreign object in a tunnel of a valuable document validator.
2. Description of Related Art
Since people require high efficiency and convenience in modern life, many kinds of automatic vending machines, such as ticket seller machine, money exchanger and teller machine are placed at many public locations. However, in some public locations some of the automatic vending machines are not under monitoring. For avoiding fraud, a validator is often installed in the automatic vending machine for identifying valuable documents. Beside that, an anti-stealing device is also installed in the automatic vending machines to prevent thieves from stealing the valuable documents in the automatic vending machines.
One of the stealing approaches is to attach a foreign object such as a wire to a valuable document and then insert the valuable document into the automatic vending machine. After identified by the validator and the credit was recorded by the automatic vending machine, the valuable document can be pulled out from the automatic vending machine by the wire. In order to prevent the stealing, a cutting device is installed in the automatic vending machine for breaking the foreign object attached on the valuable document. When the valuable document is pulled out, the cutting device can break the foreign object attached on the valuable document right away and prevent the valuable document from pulling out.
However, such a cutting device is activated by sensing the force to pull out the valuable document and has poor reliability. Therefore, there is a need to develop an effective and high-resolution detecting apparatus for the foreign object and to prevent such stealing of the valuable document.
Accordingly, the objective of the present invention is to provide an apparatus for detecting a foreign object in a tunnel of a valuable document validator.
For achieving the above mentioned objective, the present invention provides an apparatus for optically detecting a foreign object in a tunnel of a valuable document validator. The valuable document validator includes a first side and a second side opposite to the first side. The tunnel is formed between the first side and second side. The apparatus includes a light emitter, a light detector, a beam splitter, a beam combiner, a first light reflector and a second light reflector. The light emitter is located at the first side and emitting a light beam toward the second side. The light detector is located at the second side and faces the light emitter. The beam splitter is located at the first side for splitting the light beam into a first beam and a second beam. The beam combiner is located at the second side for combining the first beam and the second beam. The first light reflector is located at the first side for reflecting the second beam through the tunnel and to the second side. The second light reflector is located at the second side for receiving the second beam from the first reflector and reflecting the second beam to the light combiner.
The present invention also provides an apparatus for optically detecting a foreign object in a tunnel of a valuable document validator. The valuable document validator includes a first side and a second side opposite to the first side. The tunnel is formed between the first side and the second side. The apparatus includes a light emitted located at the first side and emitting a light beam toward the second side. The light detector is located at the second side and faces the light emitter. The light detector is a photodiode or a phototransistor for detecting the signal of the light beam.
The present invention also provides an apparatus for optically detecting a foreign object in a tunnel of a valuable document validator. The valuable document validator includes a first side and a second side opposite to the first side. The tunnel is formed between the first side and the second side. The apparatus includes a light emitter and a light detector. The light emitter is located at the first side and emitting a light beam toward the second side. The light detector is located at the second side and faces the light emitter. The light detector is a charge coupled device or a complementary metal oxide semiconductor image sensor for detecting the propagating direction and the signal of the light beam.
The present invention also provides an apparatus for optically detecting a foreign object in a tunnel of a valuable document validator. The valuable document validator includes a first side and a second side opposite to the first side. The tunnel is formed between the first side and the second side. The apparatus includes a light emitter, a light detector and a phase detector. The light emitter is located at the first side and emitting a light beam toward the second side. The light detector is located at the second side and facing the light emitter. The phase detector is located at the second side and electrically connected with the light detector for detecting the phase of the light beam.
The present invention also provides an apparatus for optically detecting a foreign object in a tunnel of a valuable document validator. The valuable document validator includes a first side and a second side opposite to the first side. The tunnel is formed between the first side and the second side. The apparatus includes a light emitter and a light detector. The light emitter is located at the first side and emitting a light beam toward the second side. The light detector is located at the second side and facing the light emitter. The light detector is a spectrum analyzer for detecting the wavelength of the light beam.
The apparatus of the present invention utilizes the light detectors for detecting the signal, the propagating direction, the phase and the wavelength of the light beam emitted from the light emitter and delivered through the tunnel. In addition, the apparatus also utilizes the beam splitter and the beam combiner for changing the propagating direction, which is a more effective way to find out if there is a foreign object in the tunnel of the valuable document validator.
A detailed description of the present invention will be made with reference to the accompanying drawings.
The valuable document validator includes a base 10 and an apparatus 20 for optically detecting a foreign object. The base 10 includes a first side 110 and a second side 120. A tunnel 130 is formed between the first side 110 and the second side 120 for delivering through a valuable document 1 such as a bill. In this embodiment, the first side 110 and the second side 120 are respectively located at two opposite sides of the tunnel 130. The front end of the tunnel 130 is used as a bill inlet 140. The rear end of the tunnel 130 is communicated to a storage device (not shown) for reserving the valuable document 1. The base 10 also includes a plurality of pulleys 150 used for guiding the valuable document 1 inserted from the bill inlet 140. Thus, the delivery of the valuable document 1 in the tunnel 130 can be more smoothly.
The apparatus 20 is used for detecting a foreign object attached on the valuable document 1. The foreign object includes opaque wire such as silk wire, linen wire or cotton wire, or transparent wire such as fishing wire or Mylar strip. The apparatus 20 includes a light emitter 210, a light detector 220, a beam splitter 230, a beam combiner 240, a first reflector 250 and a second reflector 260.
The light emitter 210 is located at the first side 110 and emits a light beam for detecting foreign object. The light emitter 210 can be light emitting diode (LED), laser diode (LD), light bulb or fluorescent tube. The light detector 220 is located at the second side 120 and faces the light emitter 210 for receiving the light beam.
The light detector 220 can be CCD, CMOS image sensor, photodiode, phototransistor or spectrum analyzer. The CCD, CMOS image sensor, photodiode and phototransistor are used for detecting the foreign object 2 in the tunnel 130 by the signal of the light beam. The spectrum analyzer is used for receiving the light beam and analyzing the spectrum of the light beam. For example, a fluorescent foreign object in the tunnel 130 can be detected by the spectrum analyzer. Therefore, when a foreign object is detected in the tunnel 130 by the light detector 220, a corresponding device can cut to the foreign object or shut down the electrical power or other measures to prevent a thief from pulling out the valuable document 1 in the valuable document validator.
The beam splitter 230 is located at the first side 110 and between the light emitter 210 and the light detector 220. The light beam emitted from the light emitter 210 is split by the beam splitter 230 into a first beam L1 and a second beam L2. One of the first beam L1 and the second beam L2 is directed through the tunnel 130 from the first side 110 to the second side 120. The apparatus 20 needs only one light beam existing in the tunnel 130. As
The beam combiner 240 is located at the second side 120 and between the beam splitter 230 and the light detector 220. The beam combiner 240 is used for combining the first beam L1 and the second beam L2 into a combined light beam and transmitting the combined light beam to the light detector 220. The beam combiner 240 can be a beam combiner plate or a beam combiner cube. In this embodiment, the beam combiner 240 is, for example, a beam combiner plate.
The first reflector 250 is located at the first side 110 for reflecting the second beam L2 through the tunnel 130 and toward the second side 120. The first reflector 250 can be a reflective mirror or a prism. In this embodiment, the first reflector 250 is, for example, a reflective mirror.
The second reflector 260 is located at the second side 120 for receiving the second beam L2 from the first reflector 250 and reflecting the second beam L2 toward the beam combiner 240. The second reflector 260 can be a reflective mirror or a prism. In this embodiment, the second reflector 260 is, for example, a reflective mirror.
When a valuable document 1 is inserted into the bill inlet 140, the valuable document 1 was delivered by the pulleys 150 through the tunnel 130. After the valuable document 1 passed through, if there is no foreign object in the tunnel 130, the light detector 220 will detect a steady light signal.
However, in case that a foreign object is attached on the valuable document 1, after the valuable document 1 passed through the tunnel 130, the foreign object will still exist in the tunnel 130. The foreign object will obstruct the second beam L2 and change the light distribution of the second beam L2. Consequently, the light detector 220 will detect the change of the light signal and judge that the existence of the foreign object in the tunnel 130.
It should be mentioned that the CCD or CMOS image sensor both have a plurality of image pixels each can sense light signal individually. The CCD and CMOS image sensor can measure the shift distance of the first beam L1 or the second beam L2 which is obstructed by the foreign object. Then the foreign object can be found in the tunnel 130. When no shift distance is measured between the first beam L1 and the second beam L2, there is no foreign object in the tunnel 130. When a shift distance of the second beam L2 caused by the foreign object 2 is measured, as shown in
Besides, the first beam L1 and the second beam L2 both from the light emitter 210 should have the same first wavelength. When the foreign object in the tunnel 130 has fluorescent substance, the fluorescent substance will convert the wavelength of part of the second beam L2 to a second wavelength. The spectrum analyzer can obtain the corresponding signals of the first wavelength and the second wavelength, and the foreign object 2 is found in the tunnel 130.
As
The light detector 420 is located at the second side 120 and faces the light emitter 410 for detecting the light beam. The light detector 420 can be CCD, CMOS image sensor, photodiode or phototransistor for receiving the light beam and analyzing the signal of the light beam.
It should be mentioned that the CCD and CMOS image sensor can measure the shift distance of the first beam L1 or the second beam L2 which is obstructed by the foreign object. Then the foreign object can be found in the tunnel 130.
Alternatively, the light detector 420 can be spectrum analyzer for detecting the wavelength of the light beam when the foreign object in the tunnel 130 has fluorescent substance. When there is no foreign object with fluorescent substance in the tunnel 130, the spectrum analyzer can obtain the corresponding band of the first wavelength of the first beam L1. When there is a foreign object with fluorescent substance in the tunnel 130, the spectrum analyzer can obtain the corresponding band of the second wavelength converted by the fluorescent substance from part of the first beam L1, and the foreign object 2 is found in the tunnel 130.
In conclusion, the apparatus utilizes the light detectors for detecting the signal, the propagating direction, the phase and the wavelength of the light beam emitted from the light emitter and delivered through the tunnel. In addition, the apparatus utilizes the beam splitter and the beam combiner for changing the propagating direction, which is a more effective way to find out if there is a foreign object in the tunnel.
Although the present invention has been described with reference to the foregoing preferred embodiments, it will be understood that the invention is not limited to the details thereof. Various equivalent variations and modifications can still occur to those skilled in this art in view of the teachings of the present invention. Thus, all such variations and equivalent modifications are also embraced within the scope of the invention as defined in the appended claims.
