JPH02171790A - Color copying device for preventing forgery of paper money or the like - Google Patents

Abstract

PURPOSE:To easily discriminate that a copied paper money or the like is forged by making the fixing ability of developer on the copied object worse when it is discriminated that an original is the paper money or the like. CONSTITUTION:Addresses (i) and (j) are set on an original platen glass 10. When it is recognized that the size of the original A is the same as that of the paper moneys at a stage that the original A is scanned, it is recognized that the original A is the paper money. When the original is conformed as the paper money, the surface temperature of a fixing roller 291, for example, is set <=100 deg.C, the image can be disturbed just by rubbing the image surface of a transfer sheet P which hands, etc. Thus, it can be easily discriminated that the copied object of the paper money is forged.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a color copying apparatus that prevents counterfeiting of banknotes.

(Prior Art) Conventionally, in order to identify the authenticity of banknotes used in vending machines, etc., and to prevent unauthorized use of counterfeit banknotes,
Various identification means have been invented and devised.

(Invention or problem to be solved) However, due to recent advances in color copying technology.

2. Description of the Related Art Banknotes, securities, and the like can now be easily and accurately copied, making it difficult to verify their authenticity.

The present invention has been made in view of the problem mentioned above, and its purpose is to provide a color copying device for preventing counterfeiting of banknotes, which can easily distinguish between copied banknotes and counterfeit banknotes. .

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a means for determining whether a banknote is a banknote, and a fixing property of a developer to the copy when the document is determined to be a banknote by the means. It is characterized by having means for worsening the condition.

(Function) When a document is determined to be a banknote, the image is not fixed sufficiently, so it is possible to disturb the image by simply rubbing your hand, etc. on the image surface of the copy. It is easy to tell that similar copies are fakes.

(Example) An example of the present invention will be described below based on the accompanying drawings.

! 1! Figure 1 is a side sectional view of the copying apparatus according to the present invention, Figure 2 is a block diagram showing the control concept of the apparatus, Figure 3 is a diagram showing banknotes placed on the document table glass, and Figure 4. 5 is a flowchart showing a banknote discrimination method, and FIG. 5 is a flowchart showing a control concept of the apparatus according to a modified embodiment.

First, an overview of the copying apparatus will be explained with reference to FIGS. 1 and 2. This copying device is a digital copying device that once converts the scanned original image into an electrical signal and stores it, and then reproduces this electrical signal as an image, and the printer section uses an electrophotographic method. This is a color copying machine.

In FIG. 1, reference numeral 10 denotes a document platen glass disposed on the upper surface of the main body l of the apparatus.
2. Short focus lens array 13, photoelectric conversion! An optical system unit 11 having a l11 element array 14 and the like is provided. The optical system unit 11 is movable along the original platen glass 10, illuminates the original A on the original platen glass loh with the illumination device 12, and converts the reflected light from the original A into a photoelectric converter via the short focus lens array 13. The document A is scanned by moving along the document table glass 10 while forming an image on the conversion element array 14 . The original image formed on the photoelectric conversion element array 14 is converted into an electric signal by the photoelectric conversion element array 14 to become an image signal, and then passes through a color processing circuit (not shown) to produce yellow (Y),
Separated into magenta (M), cyan (C), and black (K) colors, the storage device (RAM) shown in Figure 2 -
Once stored, the central processing bag is then shown in the same figure! (CP
The color-specific image signals are outputted as light emission signals of a laser (not shown) via U).

On the upper surface of the apparatus main body l below the optical system unit 11,
As shown in FIG. 1, a photosensitive drum 20 serving as an image carrier
A charger 21, a rotary developer 22, a transfer charger 23, and a transfer tram 24 are arranged around the photosensitive drum 20, and a polygon mirror 25. A mirror 26 is also provided. In addition, a cassette 27. Conveyor belt 28, fixing device 29. A paper discharge tray 30 is also provided.

That is, a light emitting signal for a predetermined color (for example, black) from the # marker is scanned by a rotating polygon mirror 25, and is imaged and exposed via a mirror 26 onto the photosensitive drum 20, which is uniformly charged by the charging lI21. Then, an electrostatic FII image corresponding to the specific color black is formed on the photosensitive drum 20. And the electrostatic latent image is developed by rotation! A specific color (black) developer 221 in the I22 converts the image into a JIl image and converts it into a toner image. On the other hand, the toner image is transferred from the photosensitive drum 20 to the transfer paper P taken out one by one from the cassette 27 and wound around the transfer drum 24 via the transfer charge s23. , if necessary, is also performed for other colors, ie, yellow (Y), magenta (M), and cyan (C), so that toner images of a plurality of colors coexist on the transfer paper P. The transfer paper P is sent to the fixing device 29 via the conveyor belt 28,
After the toner image is heated, pressurized, etc. by the fixing device 29 and fixed on the transfer paper P, the paper is discharged to the transfer paper P (l-ray 30):
It will be planted on.

The one-rotation developing device 22 includes four developing devices each having four colors of developer, namely, a black developing device 221, a magenta developing device 222. Cyan developer 223. Yellow development! ! 224
are installed, and these are connected to the central processing unit (shown in Figure 2).
are sequentially selected as necessary by signals from the CPU),
In the case of forming a full-color image, at least a magenta developer 222, a cyan developer 223 . Yellow developer 2
24 three developers are used.

First, a means for identifying banknotes, etc. (hereinafter limited to banknotes for ease of explanation) will be explained with reference to FIGS. 3 and 4.

In general digital copying machines, the optical scanning unit 11 does not store image signals during the first scan of the document, but only determines the size of the document. Identification is also made during this initial document scanning. That is, *If addresses i and j as shown in FIG. 3 are taken on the platen glass lO, and when the original A is scanned, it is recognized that the size of the original A is the same size as a banknote. This document A is recognized as a banknote.

Note that such banknote discrimination is performed using the storage device M (RAM) and central processing unit (CPU) of the digital color copying device.

Further explaining with reference to FIG. 4, i+J is the original platen glass l.
Indicates the addresses in the main scanning direction and sub-scanning direction (movement direction of the optical system unit 11) on O, and initial values are j=1, 1.
=lfJ(I) is obtained (step 2.3), N is the number that is added when it is sensed that there is a document A (in this case, a banknote) at address l and J, and the initial value is N=O or given (step 1), L (i, j) is address i,
is the signal value of the photoelectric change element array 14 at L
It is judged whether (i, j) is black, that is, a part that is not a manuscript (step 4), and if the answer is No and it is not black but a manuscript, N=N+1 and the number N is increased by one (step 5). ), the address in the main scanning direction is increased by one by setting i to i+l (step 6), and if L(i,j) is Yes and becomes black, i is set to i+1 (step 6).

It is determined whether the address i in the main scanning direction is at the end of the document table glass 10, that is, 1END (step 7).
, j) is black (step 4), and the process proceeds from step 5 to step 7. If it is i or i END, the answer is Yes, and j is set to j+1, and the address in the sub-scanning direction is set to one. Increase (step 8) 0 Next, address J in the sub-scanning direction or the edge of the original platen glass 10, that is, j
It is determined whether it is END or not (Step 9)
, if the result is No and it is not j END, i is set to 1 again (step 3) and the process proceeds from step 4 to step 9.

Also, if j is jEND, it becomes Yes and Nmi
It is determined whether n<N<Nmax (step 10). Nm1n and Nmax are given to a banknote of a predetermined size.

If the banknote falls between N or Nmin and Nmax, it is determined that it is a specified banknote, and the result is Yes, and FLAG=1 (step 11); otherwise, it is determined that it is not a banknote, and the result is No, and FLAG is =O (step 12).

Next, we will discuss countermeasures when it is determined that the document is a manuscript or a banknote.

To put it simply, the countermeasure means that the fixing state of the banknote image (developed image formed by the developer) to the transfer paper P (counterfeit copy) is deteriorated, and the developer falls off from the surface of the transfer paper P. It's about making it easier.

In order to fix the banknote image on the transfer paper P and permanently maintain the image, the above-mentioned fixing device 29 is used.
is used. The fixing device 29 is 1 as shown in FIG.
A pair of fixing rollers 291 and 2 transfer the transfer paper P bearing the image.
The image on the transfer paper ph is heated,
Alternatively, the developer is melted and fixed onto the transfer paper P by applying pressure, heating, or pressure.

First, a heat fixing type fixing device will be explained with reference to FIGS. 1 and 2. The fixing roller 29 of the fixing device 29
Out of 1,292, a heater is installed in 291 that contacts the image on the transfer paper P, and the surface temperature of this fixing roller 291 is detected with a thermistor or the like, and the temperature is controlled by the heater or a fixing temperature control unit based on the detected temperature. The surface temperature of the fixing roller 291 is 150 @ suitable for image fixing.
It is controlled to about C.

When the document is confirmed to be a banknote by the determining means shown in FIG. , the fixing temperature control unit of the fixing device 29 is controlled to control the surface temperature of the fixing roller 291, for example.
Set to 100°C or higher. Therefore, the fixing roller 29
The image of the banknote on the transfer paper P (counterfeit copy) that has passed through the 1°292 angle is not fixed sufficiently, and the image can be disturbed simply by rubbing the image surface of the transfer paper P, and the image of the banknote You can easily tell whether it is a copy or a forgery. Here, the fixing temperature control unit controls the heater of the fixing roller 291 during the second scan in which the optical system unit 11 stores the original image in the storage device t (RAM).

If it is not a document or a banknote, FLAG=O, and the image on the transfer paper is fixed at the normal fixing temperature.

Next, a pressure fixing type fixing device will be explained with reference to FIGS. 1 and 5. In pressure fixing, a pair of fixing rollers 291 and 292 of the fixing device 29 are applied to each other at a predetermined pressure through a fixing pressure control unit. (For proper fixing, the pressure is usually 10 to 20 kg/cm"), and by passing the transfer paper P carrying the image between the pressure fixing rollers 291 and 292, the image formed by the developer is transferred to the transfer paper. It is to be fixed on P.

When the document is confirmed to be a 5 banknote by the discriminating means shown in FIG. 4, a signal of FRAG=1 enters the central processing unit 1 (CPU),
), the constant pressure control of the fixing device 29 is controlled, and the pressing force between the fixing rollers 291 and 292 is set to, for example, tokg/cm2 or less. Therefore, the image of the banknote on the transfer paper P (counterfeit copy) that has passed between the fixing rollers 291 and 292 is not fixed within one minute, and the image can be disturbed by rubbing the image surface of the transfer paper P with your hand or the like. , it is possible to easily determine whether the banknote is a copy or a counterfeit.

Further, in the fixing device 29 that employs a heating and pressurizing method, the temperature and pressure may be controlled at the same time, or only one of them may be controlled.

As described above, it is determined whether it is a document or a banknote, and if it is identified as a banknote, the fixing properties of the developer are deteriorated. It is possible to easily determine whether a banknote is a duplicate or a counterfeit. In addition, the existing optical system unit 11, storage device (RAM), and central processing unit (CPU) can be used to distinguish between banknotes, and central processing is also possible for controlling the fixing device 29. Since tM (CPU) can be used, the device does not need to be large-sized and is inexpensive.

Incidentally, when it is determined that the document is a banknote, the same effect can be obtained by providing a means for changing the developer itself to one having a higher fixing temperature.

Further, in the above embodiments, prevention of counterfeiting of banknotes has been described, but it is not limited to banknotes, and of course, any type of banknotes for which counterfeiting is prohibited, such as Nankai Securities, may be used.

Further, in one or more embodiments, a digital type color copying machine has been described, but the present invention is not limited to this, and it goes without saying that an analog type color copying machine may also be used. However, in this case,
In order to separate banknotes, it is necessary to separately install a color photoelectric change element array that reads the image of the original.

(Effects of the Invention) As is clear from the above description, according to the present invention, a digital color copying device includes means for identifying banknotes, and when a document is determined to be a banknote by the means, developer Since the image forming apparatus has a means for deteriorating fixing performance, even if a banknote is copied using this copying apparatus, the image is poorly fixed, so that it is immediately recognized whether the copied banknote is a counterfeit.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a digital color copying apparatus according to the present invention, FIG. 2 is a block diagram showing the control concept of the apparatus, and FIG. 3 is a diagram showing banknotes placed on a document table glass.
FIG. 4 is a flowchart showing a banknote discrimination method, and FIG. 5 is a block diagram showing a control concept of the apparatus according to a modified embodiment. l... Copying apparatus main body, 29... Fixing device (having means for deteriorating the fixing properties of the developer), 291°292...
Fixing roller (having means to deteriorate the fixing properties of the developer)
, A... Manuscript. Patent Applicant Canon Co., Ltd. Agent Patent Attorney Ryo Yamashita Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A color for preventing counterfeiting of banknotes, characterized by having means for determining banknotes, and means for deteriorating the fixability of a developer to a copy when the document is determined to be banknotes by the means. Copying equipment.