JPS6357835B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a coin inspection device used in a coin sorting device such as a vending machine or a money changer.

BACKGROUND ART Conventionally, coin inspection devices using an oscillating coil and a receiving coil are disclosed in, for example, Japanese Patent Publication No. 57-35510, Japanese Patent Publication No. 57-35511, Japanese Patent Publication No. 55-17998,
Japanese Patent Publication No. 54-26200, Japanese Patent Publication No. 15756-1975, Japanese Patent Publication No. 57-557, Japanese Utility Model Publication No. 17257-1987, etc. are already known. However, in these conventional techniques, even if it is possible to detect differences in the materials and diameters of coins, it is extremely difficult to detect differences in the uneven pattern between the center of the coin and its periphery. Figures 2-a and 2-b are examples of such a conventionally known coin detection device, and Figure 2-a shows a coin inspection device 2 for detecting the material of a coin, in which an oscillating coil 2a and a Two receiving coils 2b and 2c are arranged facing each other between the coin passages formed between the side plates P1 and P2, and the center point of the oscillating coil 2a is placed at a position through which the center of the coin to be inspected passes. The center point of the oscillating coil 2a is the center point of the two receiving coils 2.
It was arranged to coincide with the midpoint between b and 2c. Fig. 2-b shows a coin inspection device 3 for detecting the diameter of a coin, in which an oscillating coil 3a and two receiving coils 3b, 3c are arranged facing each other on both sides of the coin passage 1, and two Receiving coils 3b, 3c
and the center point of the oscillation coil 3a,
In addition, it was placed at a position where the periphery of the coin to be inspected passed through. Coin inspection devices 2 and 3 shown in FIG. The oscillation coil 3a of the coin inspection device 3 that inspects the diameter as well as the low frequency is
A high frequency of about 100KHz is applied, and when the coin passes, the material and diameter of the coin are inspected and determined based on the peak values of the voltage waveforms obtained from each receiving coil 2b, 2c, 3b, 3c, and the authenticity of the coin is determined. I was identifying the type. However, it is very difficult to sort out two or more coins that have almost the same diameter, are made of almost the same material, and differ only by the uneven pattern on the surface of the coin or the presence or absence of holes.
The voltage waveforms obtained from voltages b, 2c, 3b, and 3c were almost the same and could not be separated.

Problems to be Solved by the Invention The purpose of the present invention is to improve the drawbacks of the above-mentioned prior art,
To provide a coin inspection device capable of sorting coins based on the uneven pattern and the presence or absence of holes, even for two or more coins in which the only difference is the uneven pattern on the surface of the coin or the presence or absence of holes.

Means for solving the problem: An oscillating coil is placed on one side of the coin passage, and a receiving coil is placed opposite the oscillating coil on the other side to inspect and determine whether the coins passing through the coin passage are genuine, false, or of different types. In order to detect and distinguish coins that differ only by the uneven pattern on the coin surface or the presence or absence of holes, we have repeatedly conducted various experiments using a coin inspection device that detects the material of coins (Second Edition). Figure a)
discovered that if the center point of the oscillating coil and the midpoint of the two receiving coils are offset from each other, even this type of coin inspection device can determine whether there are uneven patterns or holes, and the present invention is based on this. Basically, two receiving coils connected in series and in reverse phase are arranged opposite to the oscillating coil within the radius of the coin to be inspected, separated from the oscillating coil by the coin passage, and arranged in a straight line with the oscillating coil. The above problem was solved by arranging the two coils, the point and the receiving coil, with their midpoints slightly shifted from each other.

Effect When a low frequency is applied to the above oscillation coil and a coin is caused to flow down the coin path, voltage waveforms with different peak voltages are generated in the above two receiving coils depending on the coin's material, uneven pattern, and presence or absence of holes. From this voltage waveform, it is possible to determine the type of coin and whether it is genuine or false.

Embodiment FIG. 1 is a sectional view showing an embodiment of the present invention.
is a coin passage, and the coin passage 1 is formed by side plates P1, P2 and bottom plate P3, and these side plates P1, P
2. The bottom plate P3 is made of a non-magnetic material, and the coin passage 1 is inclined so that coins fall down the coin passage according to the inclined bottom plate P3. 4a
is an oscillation coil disposed on one side of the inclined coin passage 1 in the coin thickness direction, and is arranged in line with the coin to be inspected so that the magnetic flux density is maximized at the center of the passing coin to be inspected. Coils 4b and 4c constitute a receiving coil arranged on the other side of the coin passage 1, and the two coils 4b and 4c are arranged in a straight line above the oscillation coil 4a, and the coil 4
The midpoint between b and 4c and the center point of the oscillating coil 4a are arranged offset from each other, and the two receiving coils 4b and 4c are located within the approximate radius of the coin to be inspected. The coils 4b, 4c may be positioned in any direction within 360 degrees around the coils 4c, 4b as long as they are within the approximate radius of the coin to be tested from the coils 4c, 4b.

The two coils 4b of this receiving coil,
4c has substantially the same coils connected in series with opposite phases.

In this embodiment, coins are selected based on the coin's material and surface pattern, and the center of the falling coin is made to match the center of the oscillation coil 4a. If coins are to be sorted based on the difference in the number of coins, the oscillation coil 4a may be placed around the falling coins.

The two coils 4b and 4c, the oscillating coil 4a and the receiving coil described above, are connected in the same manner as in the conventional example as shown in FIG. That is, the oscillation coil 4
a is connected to an oscillator, and a discriminator circuit 7 is connected to the two receiving coils 4b and 4c via an amplifier circuit 6.
is connected to. The discrimination circuit 7 detects the voltage level of the waveform detected by the two coils 4b and 4c and discriminates the test coil as in the conventional example.

When the oscillator 5 oscillates at a frequency of about 25 KHz and the oscillation coil 4a is excited, the two receiving coils 4b and 4c are almost the same coils connected in reverse phase in series, so normally a constant low level output is sent to the coil. It is output from 4b and 4c. However, when a coin that has fallen down the coin path 1 passes through the coin inspection device, this constant low level output state is disrupted, and the voltage generated at the output terminals of the coils 4b and 4c is amplified by the amplifier circuit 6, and the coin is discriminated. The measured voltages generated at the output terminals of the two receiving coils 4b and 4c are input to the circuit 7, but differ depending on the magnetic permeability, shape, and pattern of the material of the passing coin, and this is discriminated by the discriminating circuit 7. Distinguish between genuine coins, counterfeit coins, and coin types.
Compared to conventional coin testing devices of this type, the coin testing device of this embodiment not only measures different voltage levels depending on the material of the coin, but also can detect coins that are difficult to detect with conventional coin testing devices. It has become easier to detect the unevenness of the surface and the presence or absence of holes. In particular, it has become very easy to detect the difference between the presence and absence of holes. Figure 4 shows the measured voltage waveform (output of the amplifier circuit 6) of two coins made of almost the same material and the same outer diameter, but with or without a hole, and the waveform W
1 is a coin with a hole, and waveform W2 is a waveform of a coin without a hole. In a conventional coin inspection device that inspects materials, both waveforms W1 and W2 are almost the same, making it difficult to distinguish them.However, it is possible to shift the center point of the oscillating coil 4a and the midpoint between the two receiving coils 4b and 4c. It has now become possible to noticeably detect the difference between the presence and absence of holes. In addition, Fig. 5 shows the measured waveforms W3,
W4, and in this case as well, although almost the same waveform was obtained with the conventional coin inspection device, the peak voltage of the waveform was different as shown in FIG. 5, making it easier to distinguish. Therefore, the coin inspection device of this embodiment is used in place of the conventional coin inspection device shown in FIG. 2-a for inspecting the material of the coin, and the coin inspection device for inspecting the outer diameter of the coin shown in FIG. 2-b. When used together, it becomes possible to distinguish and detect the material of the coin, the outer diameter, the uneven pattern on the coin surface, the presence or absence of holes, etc.

Further, as described above, by arranging the oscillation coil 4a around the falling coin, it is possible to distinguish between the coin's outer diameter and surface pattern.

Effects of the Invention The present invention can be used to inspect coins made of different materials by simply arranging the conventional oscillating coil and receiving coil for inspecting the material of coins by shifting the center point of the oscillating coil and the midpoint of the two receiving coils. material,
With the same outer diameter, it is possible to distinguish between uneven patterns on the surface of coins and the presence or absence of holes, and with a simple structure, it can easily make distinctions that were previously impossible, making it extremely effective. be.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the arrangement of an oscillating coil and a receiving coil of a coin inspection device according to an embodiment of the present invention, and Fig. 2-a
Figures 2-b are diagrams showing a conventional coin inspection device for inspecting the material and outer diameter of coins, Figure 3 is a block diagram of an embodiment of the present invention, and Figure 4 is an embodiment of the present invention. Figure 5 shows the detection waveforms of two coins that are made of the same material and have almost the same outer diameter, but have holes or not. The figure which shows the detection waveform of two coins. 1... Coin passage, 4a... Oscillation coil, 4b,
4c... Coil of receiving coil, P1, P2... Side plate, P3... Bottom plate.

Claims (1)

[Claims] 1. A coin inspection device comprising an oscillating coil on one side of a coin passage and a receiving coil facing the oscillating coil on the other side, wherein the receiving coils are connected in series and in reverse phase. The two coils are arranged within the diameter of the coin to be inspected and linearly opposed to the oscillation coil, and the midpoint between the two coils and the center of the oscillation coil A coin inspection device characterized in that the dots are arranged in a staggered manner. 2. The coin inspection device according to claim 1, wherein the center point of one of the receiving coils is arranged to coincide with the center point of the oscillating coil. 3. The oscillation coil is disposed at a position through which the center of the coin to be inspected passes.
Coin inspection device according to item 1 or 2.