JPS63136188A - Coin selector - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a coin sorting device for determining authenticity of coins.

[Prior Art] Generally, as a coin sorting device, a device is known in which a coil sensor is installed in a coin passage and the impedance change of the coil sensor is detected when the coin passes to determine whether the coin is genuine or fake.

FIG. 3 shows an example of the configuration of a sorting circuit in a conventional coin sorting device of this type.

In FIG. 3, a bridge circuit is constituted by a coil sensor Ll, a fixed coil 12, and two resistors R, and a sine wave of a frequency suitable for coin sorting is supplied from an oscillator 3.

The value of coil L2 is set to the value when there is no coin in coil L1, so that when there is no coin in coil Ll, voltage v, -voltage V
2 becomes zero. The voltage difference between voltage ■1 and voltage v2 is determined by the differential amplifier circuit 4. The comparator circuit 6 is powered through the rectifier circuit 5. Coin 1 in such a configuration is connected to coil sensor Ll.
Figure 4 shows the change in impedance when passing through.

In FIG. 4, when the coin 1 is not in the coil sensor Ll, the point is 0, and when the coins A, B, and C are inserted, the maximum change points are points A, B, and C, respectively. This is a coin, B,
C has different outer diameter, material, thickness, etc. Also A'
indicates the maximum change point of counterfeit money.

Next, FIG. 5 shows changes in the output voltage v3 of the rectifier circuit 5 when coins A, B, and C are inserted. Comparison circuit 6 to determine whether this voltage v3 is within a predetermined range. Coin 1 in AND circuit 7
The judgment is being made.

[Problems to be solved by the invention] However, in the conventional coin sorting circuit described above, for example, the fourth
As shown in the figure, when the counterfeit coin is located at the maximum change point A' and the genuine coin is located at the maximum change point A, the impedance difference from the zero point is almost the same value, so coin A and counterfeit coin A' can be distinguished. There were some drawbacks that I couldn't get over.

Therefore, the purpose of the present invention is to solve such problems,
The purpose of the present invention is to provide a coin sorting machine that can perform highly accurate authentication.

[Means for Solving the Problems] In order to achieve such an object, the present invention provides means for changing impedance due to passage of a coin, and detecting the change in impedance as a first voltage change. 1st
a detection means, a first comparison means for comparing whether the first voltage change detected by the first detection means is within a predetermined range, and detecting a change in impedance as a second voltage change. a second comparison means for comparing whether or not a second voltage change detected by the second detection means is within a predetermined range; The present invention is characterized by comprising a determining means for determining that the coin is a genuine coin when both the first and second voltage changes are within a predetermined range as a result of the comparison by the comparing means.

[Function] The present invention detects a change in impedance of the impedance changing means due to passage of a coin by first and second detecting means, and compares each voltage change with a predetermined threshold value. However, since the determining means determines that the passing coin is a genuine coin when each voltage change is within a predetermined range, higher identification performance can be obtained.

[Example] FIG. 1 shows an example of a configuration in an embodiment of the present invention.

The first bridge circuit includes a coil sensor L1, a fixed coil L2 . The second bridge circuit is made up of a coil sensor Ll, a fixed coil L3, and a resistor R. A sine wave is supplied from an oscillator 3 to this bridge circuit.

The value of coil 2 is set to the value when there is no coin in the coil sensor L1, that is, the value corresponding to the 0 point in FIG. 4,
The value of coil L3 is assumed to be a value below coil L2, that is, a value corresponding to point O' in FIG. The voltage difference V, -V2 passes through the differential amplifier circuit 4 and the rectifier circuit 5 to become the voltage v3, which is input to the comparator circuit 6.
In the case of A+, vA-1 coin B, VB+, VB-1 coin C
In this case, it is compared with vc+ and vc-.

The output voltage νl v 2/ from the second bridge circuit passes through the differential amplifier circuit 4 and the rectifier circuit 5 to the voltage v 3
1, and manually input it to the comparator circuit 6, and set the specified voltage range (for coin A, VA + Z A-°, for coin B, vN'+
vI,-'', and in the case of coin C, VC''Z v,-1) are compared. v when coin A and fake coin A' are immersed
Figure 2 shows the voltage change of 31.

In FIG. 2, coin A and counterfeit coin A' have different distances from position 0', so the peak values of voltage v3' are different. Therefore, the peak value of coin A is between vA+I and vA-', and the output of AND circuit 7A' becomes "1".

The counterfeit coin A' does not fall within this range, and the output of the AND circuit F' does not change to 1. This is because the output voltage from the second bridge circuit at the coin will be larger than the voltage change at the genuine coin.The reverse also occurs, but if the outputs of these AND circuits 78, 78' are The output of the circuit 8A makes it possible to reliably distinguish this type of counterfeit currency from genuine currency, thereby increasing the accuracy of sorting.

[Effects of the Invention] As explained above, according to the present invention, the impedance change value of the coil sensor due to the influence of a coin is detected as two types of voltage change values, and each of the detected voltage values is within a predetermined range. Since it can be determined whether the coin is present or not, it is possible to improve the accuracy of coin detection.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a configuration in an embodiment of the present invention; FIG. 2 is an explanatory diagram showing voltage changes in an embodiment of the present invention; FIG. 3 is a block diagram showing an example of a configuration in a conventional example; FIG. 5 is an explanatory diagram showing impedance changes in the conventional example, and FIG. 5 is an explanatory diagram showing voltage changes in the conventional example. DESCRIPTION OF SYMBOLS 1... Coin, 2... Coin path, 3... Oscillator, 4... Differential circuit, 5... Rectifier circuit, 6... Comparison circuit, 7... AND circuit. Figure 4 shows the sharpness of the dance support of the traditional dancer.

Claims (1)

[Claims] 1) means for changing impedance due to passage of a coin; first detection means for detecting the change in impedance as a first voltage change; a first comparing means for comparing whether or not the first voltage change is within a predetermined range; a second detecting means for detecting the change in impedance as a second voltage change; a second comparing means for comparing whether or not the second voltage change detected by the detecting means is within a predetermined range; and a comparison result of the first comparing means and the second comparing means; A coin sorting device comprising determining means for determining that the coin is a genuine coin when both the first and second voltage changes are within a predetermined range. 2) A coin sorting device according to claim 1, wherein the first and second detection means include first and second bridge circuits, respectively.