DE69405076T2 - Method and device for sorting coins - Google Patents

Description

Background of the invention

The invention relates to a method and a device for electronically sorting genuine and counterfeit coins.

State of the art

Existing patents, such as German Patent No. 2 646 025 and European Patent No. 0 367 921, disclose methods of determining the characteristics of a coin as two-dimensional and three-dimensional coordinates, and then separating genuine from fake coins by checking whether they belong within a predetermined area bounded by these coordinates.

If the coins to be sorted are only of one kind or type, sorting out genuine from fake coins is possible in a simple and accurate manner using such a device for sorting genuine and fake coins.

Problem to be solved by the invention

Recently, however, vending machines are expected to be operated by at least two types of coins to sell different types of products and products with higher prices. to sell, and therefore it is not unusual in foreign countries for such machines to be able to be operated by six to eight different types of coins.

If many different types of coins are allowed, they are sorted by setting a predetermined coordinate range for each type of coin. This makes the details of sorting more complicated, and the sorting takes quite a long time.

An example of a known technique for handling many types of coins is given in U.S. Patent No. 5,078,252, in which one embodiment can handle four types of coins. This device is designed to check the coins entered in a checking section, take readings representing characteristics of those coins, sort genuine and counterfeit coins according to those readings, and then direct the coins by a mechanical diverter means to either a cash channel or a return channel depending on the sorting results.

This device must be able to distinguish genuine from fake coins in, say, twenty milliseconds in order to be able to measure the coins being tested and then direct them to the correct cash or return channel. If this time is exceeded, coins that have been determined to be genuine could be directed to the return channel.

To reduce the sorting time, a high-performance central processing unit (CPU) is required, but its cost is too high.

EP 0 219 574 A discloses a method for identifying coins in which the frequency spectrum of acoustic signals generated by the vibrations of a coin upon collision with a surface is analyzed. The frequency ranges of coins that are legal in a country are clearly distinguishable from those of other coins and are chosen so that the ranges used for identification do not cause a masking effect, taking into account the limiting frequencies of the vibration. A coin is identified by comparing it with standardized frequencies, while simultaneously measuring its diameter. The coin is accepted if the frequencies of the acoustic signal and the standardized frequencies corresponding to the measured diameter match, otherwise it is rejected.

Summary of the invention

The present invention has been made in view of the problem described above and aims to provide a method and an apparatus that can very quickly and accurately separate genuine from fake coins without a special high-performance CPU.

Means to solve the problem

To achieve this goal, a method and a device for sorting genuine and counterfeit coins according to the invention consist of the following:

Claim 1 of the present invention includes a method for sorting genuine and counterfeit coins travelling along a predetermined path, wherein a plurality of type identification means are arranged along the predetermined path along which a plurality of coin types to be sorted travel, the method comprising the following steps:

setting a plurality of mutually non-overlapping assumed ranges, each of which is associated with one of a plurality of identification factors of the type identification means and which correspond to the sizes of their values; determining whether an output of any of the type identification means falls within any of a plurality of assumed ranges for distinguishing between coin types, and on the basis thereof sorting whether outputs of said type identification means fall within a closed functional range in coordinates of a plurality of dimensions having axes on which the identification factors are plotted to sort in accordance with all of the identification factors of the plurality of types.

According to claim 2, in the method according to claim 1, the closed function is a circular function or a circular function of a symmetrical form.

According to claim 3, in the method according to claim 1, the closed function is a spherical function or a spherical function of a symmetrical shape.

According to claim 4 of the present invention, there is provided an apparatus for sorting genuine and counterfeit coins which pass through a predetermined path, wherein a plurality of type identification means are arranged along the predetermined path along which a plurality of coin types to be sorted pass. This apparatus comprises:

an assumed range setting means for setting a plurality of non-overlapping assumed ranges each associated with one of a plurality of identification factors of the type identification means and corresponding to the sizes of their values;

a first sorting means for determining whether an output of one of the type identifying means falls within one of the plurality of accepted ranges for distinguishing between coin types;

a functional area setting means for setting a closed functional area in coordinates of a plurality of dimensions with axes on which the identification factors are plotted, in accordance with to sort with all identification factors of the multitude of types; and

a first sorting means for sorting whether outputs of the type identification means fall within the closed functional areas, based on the coin type determined by the first sorting means, wherein

genuine and fake coins are sorted by an initial size of the sorting agent.

According to claim 5, in the device according to claim 4, the closed function is a circular function or a circular function of a symmetrical shape.

According to claim 6, in a device according to claim 4, the closed function is a spherical function or a spherical function of a symmetrical shape.

It should be noted that in this patent specification the term "coins" includes tokens (substitute coins), medals, paper money and cards.

How it works

In the method according to claim 1, a plurality of accepted areas are set beforehand to distinguish between coin types and sorting is carried out in dependence thereon. Coins passing along the predetermined path are identified by a plurality of identification means which are set to the characteristics to be identified and the coin type is determined by checking whether at least one output signal of the identification means belongs to one of the plurality of accepted areas. The output signals of the identification means are then used to sort the coins into genuine and fake by determining whether identification details set for each coin type fall within a closed functional area in coordinates of a multitude of dimensions with axes along which the identification details are plotted.

In the method according to claim 2, the coins to be checked are sorted to determine whether they belong to all closed functional areas by using a circular function having a symmetrical shape for a circle or an ellipse in two dimensions as the closed functional area.

In the method according to claim 3, the coins to be checked are sorted to determine whether they belong to all closed functional areas by using a spherical function of symmetrical shape for a sphere or a shape with elliptical cross-section in three dimensions as the closed functional area.

In the device according to claim 4, the separation of genuine coins from fake coins by the identification means after determining the coin type is carried out by sorting the output signals obtained from the coins to be checked using a plurality of assumed ranges set by the range setting means for each of the coin types to be checked. The separation of genuine coins from fake coins is carried out by checking whether the output signal of the coin to be checked obtained by the identification means belongs to a closed functional range by using closed functional ranges in coordinates with a plurality of dimensions for each of the coin types set by the setting means.

In the device according to claim 5, the coins to be checked are checked to determine whether they belong to all closed functional areas by using a circular function with a symmetrical shape for a circle or an ellipse in two dimensions as the closed functional area.

In the device according to claim 6, the coins to be checked are checked to see whether they fall within all closed functional areas by using a spherical function with a symmetrical shape for a sphere or a shape with an elliptical cross section in three dimensions as the closed functional area.

Effects of the invention

In the method according to claim 1, since each coin type is determined by using a plurality of assumed ranges set before the genuine-false sorting, the intended type is extracted once without repeating the functional calculation for genuine-false sorting, so that rapid sorting is possible. Since determination of each coin type is made by simply comparing the sizes of values, no time-consuming calculations are required, so that high-speed processing is possible. Moreover, the number of functional calculations to separate or distinguish genuine coins from fake coins is within the performance range of the CPU.

Since in the method according to claim 2 the coins to be checked are checked to see whether they fall into all closed functional areas by using a circular function of symmetrical form for a circle or an ellipse in two dimensions as the closed functional area, sorting can be carried out by comparatively simple calculations in a short time.

Since in the method according to claim 3 the coins to be checked are checked to see whether they fall within all closed functional areas by using a spherical function of symmetrical shape for a sphere or a shape with an elliptical cross-section in three dimensions as the closed functional area, the Calculation time is slightly longer, but more precise sorting is possible.

In the apparatus according to claim 4, since each coin type is previously determined using a plurality of assumed ranges set by the range setting means before the genuine-fake sorting is carried out, the intended type is extracted once without repeating the functional calculation for genuine-fake sorting, so that an apparatus can be constructed which enables rapid sorting without using an expensive CPU. Since the determination of each coin type is carried out by simply comparing the sizes of the values, no time-consuming calculations are required, so that high-speed processing is possible. Moreover, the number of functional calculations required to distinguish or separate genuine coins from fake coins is within the performance range of the CPU used.

Since in the device according to claim 5 the coins to be checked are checked to see whether they fall within all closed functional areas by using a circular function with a symmetrical shape for a circle or an ellipse in two dimensions as the closed functional area, the details of the sorting are comparatively simple, so that a comparatively inexpensive CPU can be used and would be sufficient.

Since in the device according to claim 6 the coins to be checked are checked to see whether they fall into all closed functional areas in which a spherical function with a symmetrical shape for a sphere or a shape with an elliptical cross-section in three dimensions is used as the closed functional area, the details of the calculation are somewhat more complex, but a more precise sorting device is possible.

Short description of the drawings

Fig. 1 is a characteristic diagram of operational details of the method according to the invention;

Fig. 2 is a schematic diagram showing the structure of a coin sorting device which is an application field of the present invention;

Fig. 3 is a block diagram of a circuit arrangement included in the coin sorting device according to Fig. 2;

Fig. 4 is a flow chart of the operation of the device of Figs. 2 and 3;

Fig. 5 is a flow chart of a coin type sorting subroutine from the flow chart of Fig. 4;

Fig. 6 is a flowchart of a sorting accuracy selection subroutine from the flowchart of Fig. 4.

Description of the preferred embodiment

Fig.1 shows a characteristic diagram of operational details of the method according to the invention. In this figure, the X-axis and the Y-axis each correspond to a characteristic or feature that can be used to separate or distinguish genuine from fake coins, e.g. the material, the outer diameter or the thickness of the coin.

If such factors are separated along the X-axis and the Y-axis as shown in the figure, then a first coin, which is provided with the reference number 1, has the largest value in the direction of the Y-axis, while the second to fourth coins, which are provided with the reference numbers 2 to 4 have values that decrease sequentially along the Y axis. The second coin has the smallest value plotted along the X axis, the first coin has the next largest value, followed by the third coin and then the fourth coin.

By looking at the different values in the X-axis and Y-axis directions, it is clear that the values of the first, third and fourth coins overlap slightly in the X-axis direction, while there is no overlap in the Y-axis direction. Sorting of the first to fourth coin types can therefore be done using the values in the Y-axis direction.

In this case, the values in the Y-axis direction are divided into four ranges, from a first assumed range in which the first coin belongs to a fourth assumed range in which the fourth coin belongs (O-a, a-b, b-c and c-d), and an identification means determines or checks whether a value Py in the Y-axis direction obtained from a coin to be tested belongs to one of these assumed ranges in order to sort or classify the coin types.

Specifically, a value Py detected by an identifying means in the Y-axis direction is compared with all the limit values a, b, c and d of the above four ranges in turn, and if the value Py is found to be larger than one limit value but smaller than the next, it is assumed to belong to or fall within the second assumed range.

In the example assumed in Fig. 4, the second coin belongs to the second assumed range (bc). This means that the coin entered can be classified as a type corresponding to the second assumed range. Since this sorting is done by determining whether the measured value falls into certain ranges falls, it can be carried out by means of a simple comparison circuit.

This type of sorting is also possible in a similar way with values in the direction of the X-axis or with values determined in the direction of a Z-axis (not shown in the figure) when three-dimensional coordinates are assumed. This procedure can also be extended to sorting that takes place in a variety of axes, e.g. by setting assumed areas at an angle of the coordinates shown in Fig. 1, although this would be somewhat more complicated.

Fig. 2 shows the structure of a coin sorting device to which the present invention is applied. A coin unit 11 receives a coin M through a coin slot 12 on one side of its upper end. The coin M falls down onto a rail 13. As the coin travels down the rail 13, electromagnetic properties of the coin M are measured by coin sensors 14 and 15. A genuine-fake coin separator 16 is arranged at the right end of the rail 13, and genuine and fake coins are guided along respective genuine-fake coin paths or channels (not shown in the figure) in accordance with the operation of a separating electromagnet 17.

Genuine coins are guided along different coin tracks A, B, C and D, which are shown by dot-dash lines in Fig. 2. This separation into coin types is carried out by a separating electromagnet 19 which actuates a separating element 18. The coins intended for tracks A and B are sorted by actuating the separating element 18. The coins are sorted into each track by a sorting mechanism provided in the tracks so that they fall down into the corresponding track A, B, C or D. The coins which have fallen into the track for fake coins are ejected through a rejection slot not shown in the figure.

The circuitry included in the coin sorting device of Fig. 2 is shown in Fig. 3. In the circuitry of Fig. 3, a CPU supplies a signal of a predetermined frequency to an excitation drive circuit 22 through a frequency divider circuit 21 so that excitation currents are supplied to excitation windings 14a and 15a of the coin sensors 14 and 15. The electromagnetic field generated by these excitation currents is measured by sensing windings 14b and 14b. The measured electromagnetic field changes depending on whether a coin has passed between the excitation windings and the sensing windings and whenever a coin passes.

The electromagnetic field measured by the measuring windings 14b and lsb is supplied to integration circuits 25 and 26 via measuring amplifier circuits 23 and 24, and its peak signal is digitized by an A/D converter circuit 27 and supplied to the CPU.

The CPU performs a sorting operation on the signal thus formed in accordance with a sequence previously programmed into a ROM (Read Only Memory) 30 and, if necessary, further separates a fake coin by operating the electromagnet 17 and the coin separator 16 and the electromagnet 19 and the coin separator 18 via the drive circuits 28 and 29.

It should be noted that pins P connected to the CPU are provided to enable connection to external circuitry, and in this embodiment five such pins are provided.

Fig. 4 shows a flow chart of the operation of the embodiment according to Figs. 2 and 3. The operation The mode of operation of this embodiment is described below with reference to Fig. 4.

The device is initialized by turning on the power supply in step S1. After an error check in step S2, sorting accuracy data is input in step S3 according to a program in the CPU.

Next, in a step S4, it is checked whether a switch, e.g., a reed switch not shown in the figure, has been turned on, for example, by bringing a magnet near it. If the switch is turned on, coin type sorting accuracy selection processing is carried out in a further step S5; if it is not turned on, genuine-fake sorting processing is carried out in a further step Sb.

First, consider the coin type sorting accuracy selection processing. In this processing, the sorting accuracy is determined according to the number of coins inputted, for example, according to the coin diameter as shown in Fig. 1. Then, in a step S5, it is checked whether coins have been inputted, and if coins have been inputted, coin type processing is carried out in a step S6. Details of this subroutine are shown in Fig. 5, after which coin type processing is carried out in steps S61 to S68.

In step S61, each coin is checked to see if it is a 10 yen coin. If it is a 10 yen coin, the total number of 10 yen coins is determined in step S65 and stored in a register in the CPU. If it is not a 10 yen coin, in step S62 it is checked to see if it is a 50 yen coin, and if it is a 50 yen coin, in step S66 the total number is determined as in step S65. If it is not a 50 yen coin, in step S67 the total number is determined as in step S68. In step S63, it is checked whether it is a 100 yen coin, and in step S64 it is checked whether it is a 500 yen coin. The number of coins of each coin type is determined and stored.

After these process steps, the system returns to the main program in Fig. 4, where in step S7 it is checked again whether the reed switch is switched off. If it is switched off, the sorting accuracy is selected in step S8.

In steps SS to S7, the coin types to be changed in the sorting accuracy are determined. Here, the coin type to be changed in the sorting accuracy can be selected simply by entering a predetermined number of coins after a magnet is brought into close proximity to the reed switch and coins are entered. For example, in the case of 10 yen coins, the coin diameter becomes smaller as shown in Fig. 1, thus making the sorting level narrower when two coins are entered than when only one coin is entered. When three coins are entered, the coin diameter becomes even smaller.

Once the number of coins required to change the accuracy has been entered for the coin type to change the sorting accuracy, the magnet is removed from the vicinity of the reed switch so that the operation proceeds from step S7 to step S8.

The operation in step S8 corresponds to the number of different types of coins inputted, as shown in steps S71 to S99 in Fig. 6. In other words, in step S71, it is checked whether there is a sorting accuracy change, and if so, then in step S99, through steps S72 to S77, the number of coins inputted is stored in a register (not shown).

The same operation is performed until the number of coins is stored in step S99, in steps S78 to S84 for 50 yen coins, in steps S86 to S91 for 100 yen coins, and in steps S92 to S98 for 50 yen coins.

At the end of this storage operation, it is checked in step S9 whether there is any change. If so, it returns to step S2 for error checking and then the sorting accuracy data is read in step S3.

Then, in step S4, it is checked whether the reed switch is on or off. If it is on, the subsequent coin type sorting accuracy selection processing starting from step SS is repeated; if it is off, the genuine-fake sorting processing is initiated with step S10.

In step Sb, the standby voltages detected by the coin sensors 14 and 15 are measured. These measured voltages are used to check whether threshold values have been exceeded; the threshold values have previously been set by decision processing in step S11, in which it is checked whether coins have been inserted. In this case, after executing step S10, the program executes decision processing in step S11 to check whether coins have been inserted.

If the decision processing in step S11 shows that the threshold values previously set by the measured standby voltages have not been exceeded, the program returns to step S2; if they have been exceeded, it proceeds to the peak voltage measurement in step S12.

In this peak voltage measurement, the inserted coin is measured according to the coin sensors 14 and 15, the peak values of these measurements, as supplied to the integration circuits 25 and 26 via the gain detector circuits 23 and 24, are determined and digitized by the A/D converter circuit 27 and then temporarily stored in the CPU.

In step S13, the voltages measured in this way are deductively processed. This deductive processing checks whether the measured peak values fall within one of the assumed ranges previously described with reference to Fig. 1. This deduces the type of coin to which the input coin to be detected belongs.

At this point, a calculation is made as to whether the coin is genuine or fake. In other words, the voltages detected by a plurality of coin sensors are used to calculate whether a plurality of identification factors lie on axes in coordinates of a plurality of dimensions. For example, suppose that the values Px and Py were detected by the coin sensors for sorting in coordinates of two dimensions along the X and Y axes of Fig. 1.

In this case, the following circle equation is used:

R² = (Px - Xb)² + (Py - Yb)²

When the Z axis is added to determine coordinates in three dimensions, a spherical equation can be used.

Using the calculation result from step S14, it is checked in step S15 whether it lies in a closed functional area in coordinates of a plurality of dimensions. In the case of two-dimensional coordinates, the closed functional area has a circular symmetrical shape, eg that of a circle or an ellipse. In three-dimensional coordinates, it has a spherical symmetrical shape, eg that of a sphere or that of a shape with an elliptical cross-section. The calculation determines whether the result lies inside or outside a circle or other closed shape or a sphere or other spherical shape. If it lies inside the corresponding shape, the coin is genuine; if it lies outside, the coin is counterfeit. If it is genuine, authenticity coin processing is carried out in step S16; if it is counterfeit, it returns to step S2.

In this way, coins are sorted with an accuracy set by the number of coins entered.

Claims (6)

1. Method for sorting genuine and counterfeit coins (M) that travel along a predetermined path (13), wherein a plurality of type identification means (14, 15) are arranged along the predetermined path (13) along which a plurality of coin types to be sorted travel, the method comprising the following steps: setting a plurality of mutually non-overlapping assumed ranges (0-a, a-b, b-c, c-d), each of which is assigned to one of several identification factors of the type identification means and which correspond to the sizes of their values; determining (S13) whether an output (Py) of any of the type identification means falls within any of a plurality of assumed ranges to distinguish between coin types, and on the basis of this, sorting (S14) whether outputs (Px, Py) of the mentioned type identification means fall within a closed functional range in coordinates of a plurality of dimensions with axes on which the identification factors are plotted, to sort in accordance with all identification factors of the plurality of types. 2. A method for sorting coins according to claim 1, wherein the closed function is a circle function or a circular function of a symmetrical shape. 3. A method for sorting coins according to claim 1, wherein the closed function is a spherical function or a spherical function of a symmetrical shape. 4. Device for sorting genuine and counterfeit coins (M) which pass through a predetermined path (13), wherein a plurality of type identification means (14, 15) are arranged along the predetermined path (13) along which a multiple types of coins to be sorted pass, the device comprising: an assumed range setting means for setting a plurality of non-overlapping assumed ranges each associated with one of a plurality of identification factors of the type identification means and corresponding to the sizes of their values; a first sorting means for determining whether an output (Px, Py) of one of the type identification means falls within one of the plurality of accepted ranges to distinguish between coin types; a functional area setting means for setting a closed functional area in coordinates of a plurality of dimensions with axes on which the identification factors are plotted, to sort in accordance with all the identification factors of the plurality of types; and a first sorting means for sorting whether outputs of the type identification means fall within the closed functional areas, based on the coin type determined by the first sorting means, wherein genuine and fake coins are sorted by an initial size of the sorting agent. 5. A coin sorting device according to claim 4, wherein the closed function is a circle function or a circular function of a symmetrical shape. 6. A coin sorting device according to claim 4, wherein the closed function is a spherical function or a spherical function of a symmetrical shape.