JPS5887689A - Coin material separator - 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 electromagnetically sorts coins.

2. Description of the Related Art Conventionally, various devices have been used, for example, in public telephones, etc., to electrically or magnetically sort coins based on differences in outer diameter, material, etc.

FIG. 1 shows an example of this type of coin sorting device that is conventionally used. In the figure, 1 is a stabilization circuit, 2 is an oscillation circuit, 3 is a detection coil, 4 is an amplifier circuit, 5 is a rectifier circuit,
Reference numeral 6 denotes a comparison circuit, to which a power supply voltage V is applied by inputting the power supply signal a. The detection coil 3 includes a pair of transmitter coil 3a and receiver coil 3b, which are arranged opposite to each other across the coin path and are electromagnetically coupled to each other.

In the coin sorting device having the above configuration, the transmitting coil 3
When a coin T is placed between the receiving coil 3b and the receiving coil 3b, since the magnetic permeability differs depending on the material, the receiving coil 3b
The induced voltage changes.

Therefore, this voltage signal is amplified and rectified by the amplifier circuit 4 and the rectifier circuit 5, and the comparison circuit 6 determines whether the obtained DC voltage level falls within the reference voltage level band preset according to each coin type. The materials can be selected based on the output discrimination signal.

However, in such a coin sorting device, since the judgment level band in which the comparator circuit 6 has good resolution is limited, one set of sorting circuits having the above-mentioned configuration is used to distinguish between multiple types of coins having different magnetic permeabilities. It is difficult to sort all coins with high accuracy, and in order to obtain high sorting accuracy for various coins, it is necessary to use similar sorting circuits that have amplification circuits and comparison circuits with corresponding amplification factors and judgment level bands. It is necessary to prepare as many coins as there are types of coins to be sorted.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a coin sorting device that uses a set of sorting circuits and is capable of extremely highly accurate material sorting regardless of the luster of the coin. It is about providing.

In order to achieve such an object, the present invention provides an amplifier circuit that amplifies the receiving coil output with a variable gain circuit that changes the gain, and a coin type signal from a coin identification circuit that identifies the shape or weight of the coin. The profit is determined according to the

Hereinafter, the present invention will be explained in detail using Examples.

FIG. 2 is a block diagram showing a coin material selection circuit in one embodiment of the present invention. This embodiment is an example in which the present invention is applied to a public telephone set, and a central office power supply is used as the power supply. That is, in the figure, 10 is a power supply section, 11 is a diode bridge circuit, 12 is a power supply circuit, 13a is a dial contact Di, 13b is a shorting contact Ds, 14 is a communication circuit,
15 indicates a power switch, and the switch 15 receives the power signal a.
When the material selection circuit is activated, the power supply voltage V is supplied from the power supply circuit 12 to the material selection circuit. Note that the diode bridge circuit 11 has terminals L1. This is to keep the polarity of the input to the power supply circuit 12 constant regardless of the polarity of the DC voltage from the exchange connected to the IJ. Further, when the dial is turned, the dial contact 13a opens and closes the number of times corresponding to the dialed number to send a signal and notify the other party's number to the exchange, and the shorting contact 13b closes at this time to short-circuit the communication circuit 14. Dial pulses are prevented from entering the communication circuit 14.

In FIG. 2, 16 is a stabilizing circuit that stabilizes the power supply voltage, 17 is an oscillation circuit, 18 is a detection coil, 19 is an amplifier circuit, 20 is a rectifier circuit, 21 is a comparison circuit, and the detection coil 1B is a coin It consists of a pair of transmitting coil 18a and receiving coil 18b which are arranged opposite to each other with 22 passages in between and are electromagnetically coupled to each other. Their basic structure and operation are similar to those shown in FIG.

Here, the amplifier circuit 19 includes an analog switch 231 and a variable resistor 2 to select, for example, three types of coins.
411 Three series circuits of an analog switch 231 and a variable resistor 243, and an analog switch 238 and a variable resistor 243 are connected in parallel. These series circuits receive a coin type signal d1+ from an outer diameter identification circuit 2T, which will be described later, via level conversion buffers 251, 2511, and 258, respectively.
dB and d8 are selectively input. The gain of the amplifier circuit 19 changes depending on which of the analog switches 231, 231, and 238 is turned on. FIG. 3 shows a specific example of the configuration of such an amplifier circuit 19. In the figure, A is an amplifier, R1-R6 are resistors, and CI-CB are capacitors. Resistors R1 and H3 are bias and impedance adjusting resistors, respectively, and capacitor CI is a coupling capacitor for the rectifier circuit 20 in the next stage. Each analog switch 2 is connected between terminals TI and T3.
31.23g, 23B and variable resistance 241, 241.2
A parallel circuit of three series circuits consisting of 411 is connected.

In FIG. 2, the coin type signals di, dl, and da from the coin outer diameter identification circuit 2T are also input to the gate circuit 26 at the same time. This gate circuit 26 sends out the power signal a to the switch 15 when any one of the coin type signals di, dB, and dl is input.

In the coin material sorting device having the above configuration, when material sorting is performed, first, the outer diameter identification circuit 2T determines which of the three predetermined outer diameters the inserted coin 22 has. Identification is performed. Such a coin outer diameter identification device is configured as follows using, for example, two sets of photoelectric detectors.

FIGS. 4 and 5 are a photoelectric detector arrangement diagram and an identification logic circuit block diagram in an example of such a coin outer diameter identification device. In FIG. 4, each coin passage 30
A pair of light emitting element 31a and light receiving element 32 facing each other with
First and second photoelectric detectors each consisting of an a1 light emitting element 31b and a light receiving element 32b are mounted at regular intervals.

The outputs of the light receiving elements 32a and 32b mounted in this manner are input to the identification logic section shown in FIG.

In FIG. 5, the light receiving element 32a sends out to the timer 33 a pulse with a pulse width - corresponding to the time during which the coin 22 falling down the passage 3o is detected by the light receiving element 32a. Further, the light receiving element 32b is configured such that the coin 22 is detected by the light receiving element 32b.
The pulse width 1. corresponds to the time detected by 2b. pulses are sent to timers 33 and 34. The rising timings of the pulse outputs of both the light receiving elements 32a and 32b have a time difference of tl corresponding to the interval between the two light receiving elements. The timer 33 starts operating at the rising edge of the output of the light receiving element 32a and stops operating at the rising edge of the output of the light receiving element 32b.
is measured and sent to the arithmetic circuit 35 as a pulse output.

On the other hand, timer 34 indicates time t! is measured and sent to the arithmetic circuit 35 as a pulse output. The arithmetic circuit 35 receives the outputs of both timers 33 and 34 as inputs. /1. The ratio is calculated and the result is sent to the discrimination circuit 36. In the discrimination circuit 36, the ratio of coins with a regular outer diameter is preset as 鵞/ls, and this preset ratio t
= /ls and the ratio 'h/l input from the arithmetic circuit 35
Comparison and determination with s are performed.

Here, the falling speed of the coin 22, and hence the time 1 s required to fall a certain distance, does not change depending on the outer diameter of the coin 22. On the other hand, since the output pulse width 1t of the light receiving element 32b changes in proportion to the outer diameter of the coin 22, the ratio 'h/ls changes if the outer diameter changes. By comparing the ratio tt/ll for the outer diameter, the outer diameter of the coin can be easily identified. In this case, even if dust or the like accumulates in the passageway 30 and the falling speed of the coin 22 slows down, the output pulse width is 1. As t3 becomes larger, t3 also becomes longer, so the value of the ratio t*/ls remains unchanged. Therefore,
Accurate identification is also possible with such a force field stand.

If the result identified by the coin outer diameter identification circuit 2T in this way corresponds to any of the three predetermined outer diameters of coins, a coin type signal d is sent according to the type.
i, dB, dB each has a pulse width of 5
It is input as a pulse signal of about 0 m8 to the material selection circuit shown in FIG. Incidentally, the coins that do not correspond to the above fall into the ejection port.

In FIG. 2, the switch 15 is activated by a pulse input of one of the coin type signals di, dB, and d8, for example, dl.
is activated, and power supply voltage is supplied to this material selection circuit.

During this time, the coin 22 is transferred between the sending coil 18a and the receiving coil 1.
8b. On the other hand, this coin type signal d1
is converted to a voltage at a predetermined level by the buffer 251, and turns on the analog switch 231. At this time, the other analog switches 238 and 238 output the coin type signal d.
B, dll remains closed because there is no input. As a result, the amplifier circuit 19 has a gain determined by the variable resistor 241.

Therefore, the output voltage of the receiving coil 18b is amplified by the gain determined as described above in the amplifier circuit 19, and after being converted into a DC voltage in the rectifier circuit 20,
It is input to the comparison circuit 21. The comparison circuit 21 compares this input voltage level with a predetermined reference voltage level band,
If the coin 22 falls within the level range, it is determined that the coin 22 has a predetermined material and a determination signal is output. coin 22
If the receiving coil 18b is not made of a regular material, the output voltage of the receiving coil 18b will not be at the predetermined level, and the above-mentioned screening system will not operate normally and will not output the predetermined discrimination signal. It is possible to eliminate currency.

Here, the value of the variable resistor 241 is
1 is amplified by the amplifier circuit 19 and input to the comparator circuit 21 via the rectifier circuit 20 when the coin 22 is a regular coin of the type corresponding to the coin type signal di. The voltage level is adjusted so that it falls within the level band where the comparator circuit has the best resolution. In this case, the comparison circuit 21
Of course, the reference voltage level band is also set to a level band with good resolution. Therefore, it is possible to determine with high accuracy whether or not the coin 22 is made of a regular material.

Similarly, when the coin type signal dl or dB is input according to the outer diameter identified by the coin outer diameter identification circuit 2T, only the analog switch 231 or 238 is turned on, respectively, and the gain of the amplifier circuit 19 is 24 variable resistors each
The value is determined by 8 or 24 dollars. Also in this case, the values of the variable resistors 24m and 243 are determined by the amplifier 19 determined by the variable resistor 241 or 248, respectively.
When the coin 22 is a genuine coin of the type corresponding to the coin type signal dll or dB, the gain is amplified by the amplifier circuit 19 and passed through the rectifier circuit 20 to the comparison circuit
Since the level of the voltage input to the comparator circuit is set to a value that falls within the highest resolution level band of the comparator circuit, it is possible to confirm that the coins 22 have the proper material for coins with the respective outer diameters. It is possible to determine with high accuracy whether or not there is.

That is, the level of the voltage input from the receiving coil 18b to the amplifier circuit 19 changes depending on the type of coin 22 and the material of the coin 22. Therefore, depending on which of the coin type signals di, dl, and dB is input from the coin outer diameter identification circuit 2T, the input voltages have different levels. However, each variable resistor 241124!1
As described above, the value of 24B is set according to the materials of the three types of coins to be sorted, and these are connected to the amplifier circuit 19 according to the coin type signals di, dll, and dB. By changing the gain of
The voltage input to the comparator circuit 21 via the rectifier circuit 20 can always be at a constant level in the level band with the highest resolution of the comparator circuit 21. Therefore,
For all three types of coins having different magnetic permeabilities, it is possible to determine with high precision whether the inserted coin is a genuine coin or not.

Furthermore, the coin material sorting circuit having the above configuration is not always on standby, and the coin outer diameter identification circuit 27 determines which of the three types of coins the outer diameter of the inserted coin corresponds to. Only when the coin type signal dl, dm, or dB is sent out as a pulse with a width of 50m5, the switch 15 is turned on and the power supply voltage is changed. is supplied.

Therefore, power consumption can be significantly reduced. This is extremely useful in public telephones using central power supply.

In addition, in the above-mentioned embodiment, only the case where a circuit for identifying the outer diameter of a coin is used as the coin identification circuit has been described, but the present invention is not limited to this, and the coin identification circuit may be, for example, A circuit that identifies the weight, thickness, contour pattern, etc. of a coin may be used.

As explained above, according to the present invention, it is possible to perform material selection with extremely high accuracy for any of a plurality of types of coins using one set of material selection circuits. Further, by turning on the power switch of the material selection circuit in response to the coin type signal from the coin identification circuit, various excellent effects such as being able to significantly reduce power consumption are achieved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a conventional coin sorting device,
Fig. 2 is a block diagram showing a material selection circuit in an embodiment of the present invention, Fig. 3 is a circuit diagram showing a specific configuration example of the amplifier circuit section, and Fig. 4 is a photoelectric detector arrangement of the outer diameter identification device. FIG. 5 is a block diagram showing the identification logic circuit. 15...Power switch, 17...Oscillation circuit, 1
8a... Transmission coil, 18b... Receiving coil,
19... Amplifier circuit, 20... Rectifier circuit, 21...
... Comparison circuit, 22 ... Coin, 231, 231,
231...Analog switch, 241.241,2
48...Variable resistance, 26...Gate circuit, 2T
... Coin outer diameter identification circuit, 30 ... Coin passage, 3
1a, 31b... Light emitting element, 32a, 32b...
・Light receiving element, 33.34... Riima, 35...
Arithmetic circuit, 36...Discrimination circuit. Patent applicant: Tamura Electric Co., Ltd. Agent Masaki Yamakawa (1811 people) Figure 1 Figure 2

Claims (1)

[Claims] In a coin sorting device that identifies the shape or weight of a coin by a coin identification circuit, and then sorts the material of the coin by a coin material sorting circuit, the coin material sorting circuit includes a transmitter arranged opposite to each other across a coin passage. a coil and a receiving coil, an amplifier circuit that amplifies the output of the receiving coil, a rectifier circuit that converts the amplified output into a DC voltage, a comparison circuit that compares the rectified output with a reference value and outputs a discrimination signal; A coin sorting device comprising a variable gain circuit that changes the gain of the amplifier circuit, and configured to control the variable gain circuit in accordance with a coin type signal sent from the coin identification circuit.