JPS59221777A - 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 The present invention relates to a coin sorting device that sorts coins using a detection coil arranged in a coin orbit.

In public telephones, vending machines, etc., a detection coil is installed in the coin track to detect the thickness, diameter, etc. of the inserted coin.
It determines the authenticity and type of k'J. That is, the output voltage of the detection coil changes depending on the presence of a coin, and the amount of change corresponds to the thickness, diameter, etc. of the coin. Therefore, the thickness, diameter, etc. of the coin are detected based on the amount of change in the output voltage of this detection coil.

However, since the amount of change in the output voltage due to thickness, diameter, etc. is extremely small, if the output voltage of the detection tube changes due to temperature change, accurate discrimination becomes impossible. In particular, public telephones, vending machines, and the like are often installed outdoors, where temperature changes are significant, making highly accurate discrimination impossible.

As a countermeasure for this, conventionally, for example, the temperature compensation die A-
Attempts have been made to add a special temperature compensation circuit such as a card, but the circuit becomes complicated and sufficient temperature compensation cannot always be obtained.

The present invention solves and overcomes the above problems.
Of the multiple detection coils arranged in a melon shape, the output voltage of one of the detection coils that is not detecting a coin is used as a reference, and the output voltage of the other detection coil that is detecting a coin and the detection coil that is not detecting a coin are determined. It is an object of the present invention to provide a coin sorting device that removes temperature fluctuations that are equally heard in both signals by obtaining a voltage difference between the output voltage and the output voltage.

Hereinafter, the present invention will be described in detail with reference to the drawings.

In FIG. 1, the arrowhead 1 shows the coin trajectory.

As shown in Fig. 2.3, the coin track 1 has a cover 3 mounted on the top side of a base plate 2 which is inclined with respect to the vertical, parallel to the cover 3 at a predetermined distance apart, and a cover 3 on the bottom side of the cover 3. , the rail 4 for guiding coins is installed at an angle with respect to the horizontal line, and the coin C inserted from the slot 5
is in contact with the upper surface of the substrate 2, and the circumferential end surface C'' is in contact with the rail 4, and then falls onto the rail 4.

The coin track 1 (bent in the shape of a rectangle) is installed at the end of the upper half of the sorting track 1a to remove unsuitable coins from the track and drop them into the return slot 6. 1) A 1-exclusion lever 7 is provided.

At a position close to the input port 5 of the sorting track 1a, a thickness detection coil T is installed on the J2 surface side of the J bar 3 so that its detection surface faces the coin passage (as shown in FIG. 2). The coins are attached to the rails 4 and are placed close to the rail 4 so as to be covered by regular coins of the smallest diameter.

On the downstream side of the thickness detection coil T on the sorting track 1a,
As shown in FIG. 3, the diameter detection coil D is installed on the bottom side of the substrate 2 so that its detection surface faces the coin passage, and covers a part of the regular coin with the smallest diameter, and also covers a part of the regular coin with the largest diameter. It is installed at a position lζ slightly away from the rail 4 so that the entire □ is not covered by coins.

FIG. 5 is a block diagram of an electric circuit for sorting coins using detection coils T, .

In FIG. 5, 11 is an oscillator that outputs a rectangular wave oscillation signal of a predetermined frequency, and 12 is a frequency divider.

The one-wavelength detection coil T is excited by a rectangular wave signal of a predetermined frequency from a frequency divider 12 that divides the rectangular wave oscillation signal of the oscillator 11, thereby generating an alternating magnetic field. The thickness detection coil T forms a parallel resonant circuit with the capacitor I 13, and when no coin is present, the output voltage appearing at both ends of the coil is maximized in tune with the frequency from the frequency divider 12. . When a coin passes through the thickness detection coil T while covering it, the impedance of the thickness detection coil T changes and goes out of tune, causing the output voltage to drop. As shown in Fig. 2, this impedance change is larger as the distance from the surface of the coin C to the bottom of the thickness detection coil is smaller (that is, the thicker the coin C is). The output voltage decreases as the thickness increases.

The diameter detection coil D is similarly magnetized by a rectangular wave signal of the same frequency from the frequency divider 12 to generate an alternating magnetic field. , the diameter detection coil D forms a parallel resonant circuit with the concave coil 15, and the output voltage is similarly maximized when no coin is present. When a coin passes through the diameter detection coil D with part of it covered, the impedance of the diameter detection coil D changes as well, but as shown in Figure 4, the larger the diameter of the coin, the more the coin passes through the coil. Since the area covering D becomes larger, the change in impedance becomes larger, and the output voltage becomes lower.

Thickness detection coil T and diameter detection coil D1 Capacitor 13
The condensation method 15 has the same properties and characteristics.1. W
The coefficient is used.

In Fig. 5, 43.44 is a resistor, 17.1 is an AC amplifier that amplifies the output signal of the detection coils T and D, respectively, and 21.23 is the same frequency as the signal that drives the detection coils T and D. This is a DC conversion circuit that samples and holds the output signal of the AC amplifier 17 and 19 using the sampling pulse from the frequency divider 12.

25 and 27 are differential amplifiers, the output signal of the DC conversion circuit 21 is input to the non-inverting input terminal of the differential amplifier 25, and the output signal of the DC conversion circuit 23 is input to the inverting input terminal. Conversely, the output signal of the DC conversion circuit 23 is input to the non-inverting input terminal of the differential amplifier 27, and the output signal of the DC conversion circuit 21 is input to the inverting input terminal.

29 and 31 are peak hold circuits that detect the lowest values of the output voltages of the differential amplifiers 25 and 27, 33 are two peak hold circuits, and 31 is a peak hold circuit that converts the held analog voltage into a digital value. D converter, 34 is △/D
The two digital values from the converter 33 are compared with the two pre-stored digital values related to regular coins to determine the authenticity and type of the coin, and if the coin is a valid coin, the removal lever 7 is activated. emit a proper signal to allow the coin to pass]
This is a judgment circuit.

36 and 37 respectively receive the output signals of the differential amplifiers 25 and 27, and when the output signals have fallen below a predetermined level, the LrL I+ signal is outputted to the Schmidts 1.
The Schmitt trigger circuit 36 is a Heli Trigger circuit.
``At the falling edge of the signal, a reset signal is output to the two peak hold circuits and 31 via the differentiating circuit 38, and at the rising edge, the digital signal obtained by converting the voltage level of the two peak bold circuits is read into the judgment circuit 3/1. The Schmitt trigger circuit 37 triggers the determination circuit 3 at the rising edge of the “L” signal.
4 reads the digital value obtained by converting the voltage level of the peak hold circuit 31.

39 is a 1-transistor, /1. O is an electromagnet that is energized by conduction of the 1-transistor 39, and 41 is a protection diode.

As shown in FIG. 6, the removal lever 7 is rotatably attached (pull) to the lower surface of the base plate 2, and is attracted by the permanent magnet 42 so that the tip 7a protrudes into the coin track 1. When the electromagnet 40 is energized, its magnetic force is generated in a direction that cancels out the attractive force of the permanent magnet 42. Therefore, the coin is removed from the removal lever 7.
It pushes away the tip 7a and advances to the accumulation trajectory nlb.

FIG. 7 is a time chart showing the circuit operation of FIG. 5, and the circuit operation of FIG.
C.Explain.

(a) in FIG. 7 is a rectangular wave signal sent from the frequency divider 12 to the thickness detection coil T and diameter detection coil D, (+) >
These are sampling pulses of the same frequency sent to the Ij DC conversion circuits 21 and 23.

The high frequency component of the rectangular wave is removed from the thickness detection coil 7 by a common I-circuit with the condenser 13, and a sine wave (Fi) is output.The solid line in the figure (C) indicates the AC amplifier. 17.The amplitude of this sine wave signal varies depending on the thickness of the coin while the coin passes through the thickness detection coil T (indicated by the symbol [A] in Fig. 7). becomes smaller accordingly.

In the DC conversion circuit 21, this sine wave signal is converted to J as shown in (b).
Sample and hold with the limp link pulse, as shown in Figure 7 (
It is converted into a change in DC voltage as shown by the chain line in C).

The diameter detection coil [) l) 11 and others similarly output a sine wave signal, and while the coin passes through the coil D (indicated by the symbol "mouth" J-0 in Fig. 7), the amplitude of the signal changes depending on the diameter of the coin. becomes smaller according to

This sine wave signal is similarly sent to the DC converter circuit 23 as shown in FIG.
) is converted into a change in DC voltage as shown by the chain line.

When the coin passes through the thickness detection coil T, there is no coin in the nI diameter detection coil D, and therefore the DC conversion circuit 2
The output voltage of No. 3 does not decrease. Therefore, the variation in the output voltage of the thickness detection coil T when a coin passes is outputted as a differential voltage signal from the differential amplifier 25, using the unchanged output voltage of the diameter detection coil D as a reference voltage. Since the thickness detection coil T and the diameter detection coil D use coils and capacitors with the same characteristics and the same temperature coefficient, the amount of variation in output voltage due to the preparation is the same. Therefore, the differential amplifier 25 provides an output signal in which the temperature variation is removed from the common mode voltage.

7(1) shows the output of the differential amplifier 25.

While the coin is passing through the diameter detection coil D, there is no coin present in the thickness detection coil 1, and the output voltage of the 1ζ DC variable voltage circuit 21 does not decrease. Therefore, when a coin passes, the fluctuation in the output voltage of the J3 diameter detection coil D is outputted as a differential voltage signal from the differential amplifier 27 by using the unchanged output voltage of the J diameter detection coil T as the flu voltage. Temperature fluctuations are immediately removed. FIG. 7 ((1) shows the output signal of the differential amplifier 27.

Whenever the output voltage of the differential amplifier 25.27 falls below a predetermined level, the Schmitt trigger circuit 36.37
7 (i) and (j) respectively indicate the output signals of Schmidts 1 to 1 to Riga circuit 36 and 37.
[-"' At the falling edge of the signal, the differentiating circuit 38
Pulse (Figure 7 (1 ()) with two peak bold circuits,
31 and output the lowest value for the previous coin to Reren1~
and each lower value for the coin in transit. FIGS. 7(e) and 7(11) show the output j signals of the peak hold circuits 29 and 31, respectively.

At the rising of the "L" signal of the Schmidts 1-1-Riga circuit 36, the judgment circuit 34 converts △/D into the converter 33, J, which is held in two peak bold circuits, and converts the Iζ minimum voltage into a digital value. and read this digital value into the judgment circuit 34.Similarly, the Schmidts 1-trigger circuit 3) 7's ''
Rise of L°° signal 11. The judgment circuit 34 is an A/D
The lowest voltage held in the peak bold circuit 31 is converted into a digital value by the converter 33, and this digital value is read into the determination circuit 34. The determination circuit 34 presets these two types of digital values and compares them with the digital values of the Iζ2 scale to determine the authenticity and type of the coin.

As explained above, the coin of the present invention) is
The output type 1 of the detection coils T and D fluctuates by J in temperature, and the temperature fluctuation is differentially removed by the differential amplifier J, -), so a simple circuit is sufficient. 41 temperature compensation is realized, and highly accurate coin sorting becomes possible.

[Brief explanation of drawings]

FIG. 1 is a schematic front view showing the arrangement of the coin orbit (pull n - pull) in one embodiment of the present invention, and FIGS. It, l-111 sectional view, Fig. 4 is a diagram showing the relationship between the coin size and the installation position of the detection coil, Fig. 5 is a block diagram showing the circuit configuration, and Fig. 6 is a sectional view showing the tJ + removal lever configuration. 7 is a block diagram showing the operation of the circuit shown in FIG. 5. 1... Coin track, 2... Board, 3...
...Cover, 4...Rail, 5...
・Inlet, T...Thickness detection coil, D...
...Diameter detection coil, 7...Exclusion lever, 11
...Oscillator, 12... Frequency divider, 17.
19...AC amplifier, 21.23...
DC conversion circuit, 25.27...Differential amplifier, 2
9.31...Peak hold circuit, 33...
... A/D converter, 3/1 ... Judgment circuit, 3
6...Schmidts 1~: Heliga...Differential circuit, 37...Schmitts 1-1~Riga circuit. Patent Applicant Anritsu Electric Co., Ltd. Agent Patent Attorney Makoto Hayakawa Figure 1 / □ Figure 2 Figure 4 Figure 3

Claims (1)

[Claims] A plurality of detection coils are sequentially arranged at a certain distance along the coin trajectory to detect the presence of a coin in the coin trajectory, and an alternating magnetic field generating means for applying an alternating magnetic field to the detection coil; a plurality of DC conversion circuits each of which detects a change in the alternating magnetic field due to the presence of a coin and outputs a detection signal, and converts the signal into a DC signal; and a DC output signal of the DC conversion circuit. and a detection circuit for outputting a detection signal for coin sorting based on the detection circuit; wherein the detection circuit receives a detection signal from one detection coil during coin detection; The difference signal between the output signal of the DC conversion circuit and the output signal of the DC conversion circuit that receives the detection signal of the detection coil that is different from the detection coil that is not detecting a coin is converted to the DC conversion circuit of the detection coil that is not detecting a coin. A coin sorting device characterized by being a differential amplifier that outputs an output signal based on a circuit output signal.