JPS584393B2 - Sorting oscillation circuit for coin sorting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for automatically sorting coins, a vending machine,
This relates to a selective oscillation circuit in a device that sorts and sorts various coins in coin handling devices such as automatic currency exchange machines and automatic accounting machines, rejects counterfeit coins, and identifies only genuine coins.

Conventionally, in this type of coin sorting device, different types of coins have been sorted and sorted based on the external dimensions and weight of the coins.

The method of sorting coins by measuring their outer dimensions does not have the ability to sort out fake coins with the same outer dimensions, making it impossible to distinguish them from regular circulating coins.

Furthermore, the method of sorting coins by measuring their weight does not have the ability to sort pseudo coins of the same weight.

Therefore, a coin selector that uses both external dimensions and weight is generally used.

However, with the gravimetric method, increasing the speed of the sorting process makes it difficult to sort with high precision, and there was a runner-up in which the sorting accuracy decreased.

In addition, artificially created pseudo coins with the same external dimensions and weight were mechanically indistinguishable from officially circulating coins.

Therefore, it has been proposed to use a unique mechanical frequency based on the physical characteristics of a coin as an identification means.

That is, a speaker and a pressure-sensitive sensor are provided in an inclined coin passage across the passage, a stopper that collides the inserted coin sliding in the passage and holds the inserted coin between the speaker and the pressure-sensitive sensor, and a speaker and a pressure-sensitive sensor. An oscillation circuit with a positive feedback path is connected in series with the sensor, and a mechanical filter consisting of an inserted coin, a speaker, and a pressure sensor is inserted into the feedback path to detect the mechanical natural frequency of the inserted coin. The oscillation signal is feedback-amplified and oscillated at approximately the same frequency as the coin, and the oscillation signal at the mechanical vibration frequency of the coin is frequency-selected by a resonant circuit and extracted as a single-mode signal to separate different types of coins.

Therefore, in this type of sorting device, when the inserted coin hits the stopper and is located between the speaker and the pressure sensor, the positive feedback path of the oscillation circuit is closed.

When the coin hits the stopper, the impact vibration or noise in the circuit is amplified and appears in the output of the oscillation circuit, which energizes the speaker, and the acoustic output from the speaker causes the coin to vibrate, and the vibration is transmitted to the pressure sensor. is sensed.

Therefore, if the vibration of the coin and the vibration of the speaker are in opposite phases at this time, the vibration of the coin will be attenuated and will not vibrate after all.

This phenomenon may occur even between coins of the same type due to differences in physical quantities such as size, shape, and weight of the coins.

An object of the present invention is to prevent this phenomenon and ensure that the oscillation circuit oscillates.

The object of this invention is to provide an astable multi-by-break which operates simultaneously with the detection of the insertion of coins to be sorted, thereby inverting the feedback phase of the oscillation circuit sequentially and continuously, while increasing the magnitude of the output of the oscillation circuit. is detected through a rectifier circuit, and when the value reaches a certain value, the astable multi-byte break is locked.

The present invention will be described below with reference to embodiments shown in the accompanying drawings.

In FIG. 1, coins 4 inserted through the input port 2 of the coin sorting machine 1 are temporarily stopped by an arcuate stopper 5 in the inclined passage 3.

A pressure sensor 7 and a speaker 6 are provided in the passage 3 so as to face each other with the temporarily stopped coin 4 interposed therebetween.

The pressure-sensitive sensor T consists of a piezoelectric element 7' made of, for example, barium titanate, a hemispherical plastic chip 8 placed on top of the piezoelectric element 7', and a base 9 having a certain mass placed on the bottom of the element 7'. , is fixed in the holder 10, and the space between the holder 10 and the base 9 is filled with an elastic material.

In this case, the pressure sensor 7 is arranged so that its tip 8 protrudes into the passage 3 and its head supports approximately the center of one side of the coin 4 that has been stopped.

On the other hand, the speaker 6 is arranged so that it can effectively apply sound waves to the opposite side of the coin 4 placed obliquely on the tip 8 of the piezoelectric element 7'.

Reference numerals 11 and 12 denote a light emitting diode as a light source and a phototransistor as a light receiving element, respectively. As is well known, when the coin 4 blocks the light-heat path, a coin passage detection pulse is generated in the phototransistor 12.

If the passing coin is a perforated coin, the pulse is 2.
One occurs.

This coin passage detection pulse is amplified by the amplifier 14, and then sent to the Schmitt trigger circuit 15 at 1 and 4 in FIG.
The discrimination start signal S1 is waveform-shaped as shown in 15 in the figure.
This activates the monostable multi-by-break 16 as a waiting time setting circuit.

At this time, the output pulse S5 (third
As shown in the figure, the power to the astable multi 17 is turned on, and the astable multi 17 begins to operate.

On the other hand, the piezoelectric element T' of the pressure sensor 7 is connected to the input terminal of an amplifier 18, and the speaker 6 is connected to the output terminal of a second amplifier 23 following the amplifier 18, forming one oscillation circuit. ing.

In this case, the pressure sensor 5, the speaker 6, and the coin 4 interposed between them constitute one type of mechanical filter.

That is, the coin 4 that is acoustically driven by the speaker 6 has a steep filtering characteristic that vibrates only at the same vibration frequency as the coin's natural vibration frequency and hardly vibrates at other frequencies.

A gate 19 and a limiter 2 are connected between the amplifiers 18 and 23.
A series circuit consisting of a phase inverter 20 and a gate 21 is connected to the gate 19 in parallel.

The above-mentioned astable multi 17 is connected to these two gates 19 and 21.
It is provided to control the opening and closing alternately.

A phase changeover switch circuit consisting of gates 19 and 21 and a phase inverter 20 extracts output signals having a phase difference of 180 degrees from each other from the collector and first transistor sides of the transistor in the previous stage, which is used for example with the emitter grounded, and This can be configured such that the output of the astable multiplier 17 is applied to the control input terminals of the transistors that are respectively switched.

When the inserted coin hits the stopper 5 and is positioned as shown in FIG. 1, the positive feedback path of the oscillation circuit is closed.

That is, when the coin 4 hits the stopper 5, the impact vibration or noise in the circuit is amplified and appears in the amplifier 23, which energizes the speaker 6, and the acoustic output from the speaker causes the coin 4 to vibrate, and the vibration is It is sensed by the pressure sensor 7.

At this time, if the vibration of the coin 4 and the vibration of the speaker force 6 are in opposite phases, the vibration of the coin is attenuated and does not vibrate after all.

This phenomenon may occur even between coins of the same type due to differences in physical quantities such as size, shape, and weight of the coins.

To prevent this phenomenon, the astable multiplier 17 operates for a certain period of time to switch the phase and positive feedback is locked at such a stable point or state.

This is done as follows. First, as mentioned above, the astable multi 17 starts operating when the phototransistor 12 detects a passing coin, and gates 19 and 21 are alternately opened and closed while the monostable multi 16 has an output. .

Then, when the coin 4 comes to the position shown in Fig. 1, the gate 19.2
1 is opened, positive feedback is applied and oscillation occurs.

At this time, a relatively large output appearing in the amplifier 23 is converted into a bias potential by the rectifier circuit 24 and applied to the astable multi 17, thereby locking the astable multi 17 to the operating state at that time, that is, the stable point on the oscillation side. .

In this way, the gate that matches the oscillation condition is opened continuously, and the oscillation circuit causes selective oscillation at the coin's natural frequency.
An oscillation output signal S2 of a constant voltage is taken out at the output terminal of the amplifier 23.

As mentioned earlier, this oscillation frequency is determined by the type of coin, and is approximately 13 KHz for a 10 yen coin and approximately 1 kHz for a 100 yen coin.
You can get a frequency of about 19 to 20 KHz with 8 KHz and 50 yen.

In FIG. 2, the oscillation output signal S2 (drawn as a pulse in FIG. 3 for ease of drawing) is waveform-shaped by a Schmitt trigger circuit 27, and then sent to a one-cycle selection circuit 30. Added.

In that case, the Schmitt trigger circuit 27 includes a rectifier circuit 25
A continuous wave/shock wave sorting circuit oscillation confirmation circuit consisting of a The circuit 27 is configured not to operate.

That is, the oscillation output signal is rectified by the rectifier circuit 25 (the third
83) in the figure, the AND circuit 26 is opened only when the DC potential reaches a certain value.

When the output signal S2 is a continuous wave, the AND circuit 26 has approximately 50
Opens after a delay of 0 μSeC, Schmitt trigger circuit 27
An oscillation pulse signal S4 shown at 4 in FIG. 3 is taken out from.

On the other hand, the monostable multi 16 (first
) is the waiting time as shown in 5 of Fig. 3, for example 200
After μsec, it is inverted and triggers the monostable multi 28 as a processing time setting circuit, whereby the monostable multi 28 generates the processing time setting signal S12.

This processing time setting signal S12 passes through an AND circuit 29 and operates a one-period selection circuit 30.

The one-period selection circuit 30 consists of a main flip-flop 32 and an auxiliary flip-flop 33 connected in series, and an AND circuit 31 placed in front of the main flip-flop 32. It has a configuration in which it is connected to one input terminal, and both flip-flops 32 and 33 are set at the rising edge of the above-mentioned processing time setting signal S12.

The reset output terminal of the auxiliary flip-flop head knob 33 has a high potential in this state, and is applied to the AND circuit 31.

The AND circuit 31 is opened by the output of the flip-flop 33 and the output from the aforementioned Schmitt trigger circuit 27, and receives the oscillation pulse signal S from the Schmitt trigger circuit 27.
4 are added to the main flip-flop 32 in sequence.

The flip-flop 32 is inverted at the first input pulse pulse and enters the reset state, and then at the second input pulse S''
Return to normal at 4.

This one-time set/reset operation of the main flip-flop causes the auxiliary flip-flop 33 to invert, close the AND circuit 31, and latch the flip-flop 32.

It is the signal at the set output terminal of main flip-flop 32 that is taken as the output of the one period selection circuit.

Therefore, the one-cycle selection circuit 30, as shown at 6 in FIG.
1 which operates for exactly one period of the input oscillation pulse signal S4 and has a pulse width corresponding to one period of the oscillation pulse signal S4.
A periodic pulse S6 is generated at terminal 34.

This pulse S6 is applied to one input terminal of the AND circuit 41.

The other input terminal of the AND circuit 41 has, for example, approximately 10M
A Hz crystal oscillator 40 is connected, and the output pulse train S7 of this oscillator 40 is extracted by an AND circuit 41 by a width corresponding to the pulse S6.

This extracted pulse train S8 is counted by a 1000-decimal counter composed of a counter unit composed of three periodic counters 42, 43, and 44 and a decoder 45.

This count value is determined by the ratio between the natural vibration frequency of the coin and the oscillation frequency of the oscillator 40.

However, even if coins of the same type are actually correct, there is some deviation in the natural vibration frequency of each coin.

According to actual measurement results, the natural vibration period of each coin is 51.5 to 53.5 μsec for 50 yen. 542-55 for 100 yen
．． 7 μsec, 73.5 to 77.5 μsec for 10 yen,
It turns out that there is a margin of margin.

Therefore, when the oscillation frequency of the oscillator 40 is 10 MHz, the counts are 515-535, 542-557, 735-
Correct coins between 775 and 50 yen, 100 yen,
There will be a value indicating 10 yen.

For convenience, the smallest numerical value representing each margin will be referred to as the leading value, and the largest numerical value will be referred to as the trailing value.

OR circuits 46, 47, and 48 formed by combining three NAND gates are connected to each output terminal of the decoder 45 that displays the first value and the last value of each margin. The output terminals are AND circuits 50 and 5, respectively.
In the drawing, it is connected to one input terminal of 1.52.
The decoder 45 and each OR circuit are connected by two solid lines, but since the number displayed on the decoder is three digits, they are actually connected by three lead wires depending on the digit of each digit. .

The AND circuit 50 and AND circuits 51 and 52 are opened and closed depending on whether or not there is a hole for an inserted coin.

That is, a flip-flop 56 for determining the presence or absence of holes is provided, and its input terminal is connected to the output terminal of the Schmitt trigger circuit 15 shown in FIG. The other inverse output terminal Q is connected to the other input terminal of the AND circuit 50.

When there is only one output pulse of the Schmitt trigger circuit 15 in FIG. In the case of a perforated coin, two output pulses are generated in the Schmitt trigger circuit 15, flip-flop 56 is inverted and AND circuit 50 is opened.

Therefore, depending on whether the inserted coin has a hole or not, the flip-flop 53 will operate or the flip-flop 54.5 will operate.
5 will be activated.

Since they are connected as described above, each OR circuit 46, 47 .
48 is the first count when the counter starts counting from 0 and reaches the first value, and the corresponding signal appears in the decoder 45.
The output pulse (leading value pulse is produced and the flip-flop 53 or 54.55 is inverted via the subsequent AND circuit 50 or 51, 52, respectively, while the count further advances and a signal corresponding to the decoder 45 appears at the trailing value. then a second output pulse (trailing value pulse) is produced which respectively inverts the flip-flop 53 or 54, 55 again and returns it to its previous state.

Therefore, the number of pulses of the pulse train S6 extracted by the AND circuit 41 corresponding to the period width of the natural vibration frequency of the inserted coin (pulse width of one period pulse S6) is now determined by the decoder 45.
Let us assume that the value is within the set margin defined by , that is, between the first value and the last value.

For such a coin, when the count reaches the first value, a first value pulse is generated in the OR circuits 46, 47, and 48, but a last value pulse is not generated, so the output pulse of the OR circuit is as shown in 9 in Figure 3. Only one shot per day.

Therefore, the flip-flops 53, 54, and 55 remain inverted at the leading value pulse, indicating that the inserted coin is a true coin.

Conversely, if the number of extracted pulses is not within the set margin, that is, less than the leading value or greater than the trailing value, neither the leading value pulse nor the trailing value pulse appears, or both appear (the 18) in Fig. 4, the flip-flops 53, 54, and 55 either do not flip or flip, but even if they flip again, they flip again and return to their original state, indicating that the inserted coin is a fake coin.

As an example, the case where a real 50 yen coin is inserted will be explained as follows.

In this case, it is assumed that the number of pulses extracted corresponding to the period width of the natural vibration frequency of the inserted 50 yen coin is 525.

Since the 50 yen coin is a coin with a hole, only the AND circuit 50 is opened by the reverse output of the flip-flop 56.

The counter starts counting from 0, passes the initial value 515 for the 50 yen coin, and ends counting up to 525.

Therefore, the OR circuit 46 which receives the leading value 515 and the trailing value 535 generates only the leading value pulse S6 (FIG. 3) when the counter reaches 515.

Therefore, the flip-flop 53 remains inverted, and 5
An output signal SB is generated at the output terminal B belonging to 0 yen, indicating that the inserted 50 yen coin is a real coin.

As a second example, a case where a fake 10 yen coin is inserted will be explained.

In this case, it is assumed that the number of pulses extracted corresponding to the period width of the natural vibration frequency of the inserted 10 yen coin is 780.

Since the 10 yen coin is a non-perforated coin, AND circuits 51 and 52 are opened by the output of flip-flop 56.

Leading value 735 and trailing value 77 for a true 10 yen coin
The OR circuit 48 which receives 5 as an input outputs a leading value pulse S13 (
4) to invert the flip-flop 55,
Then, when the count further advances and reaches 775, a trailing value pulse S//8 is generated and the flip-flop 54 is output.
The counter that returns to the previous state continues to count to 78.
Ends with 0.

Therefore, no output signal is generated at output terminal 0, which belongs to 10 yen.

In addition, while the counter counts up to 780, the count number is 5.
At 42, the flip-flop 54 is reversed, but at count number 557, it is reversed again and returns to its original state, so 10
No output signal is generated at the output terminal A that belongs to 0 yen either.

The advantage of the above method of sorting out genuine and fake coins is that when the number of extracted pulses is within or outside the set margin width, and even if the number is larger than the leading value, the leading pulse and trailing pulse will appear, so 7 flip-flops will occur. Flip again and return to the original state,
The point is that it indicates that the coin inserted is a fake coin.

The outputs of flip-flops 53, 54, and 55 are connected to 50 yen and 10 yen through AND circuits 57, 58, and 59, respectively.
Sorting output signals SB, S representing true coins of 0 yen and 10 yen
It is taken out as A, SC.

This sorting output signal is sent as an input to a coin counter in a vending machine, for example.

The AND circuits 57, 58, and 59 function to remove the pulse SIQ caused by the leading value pulse and trailing value pulse before oscillation.

There is some time delay after the coin is inserted until the oscillation of its natural vibration frequency occurs, and while the number of pulses due to this oscillation is being counted, the pulse S19 appears at the sorting output terminals A, B, and C. This is because it is necessary to make sure that there is no such thing.

Therefore, AND circuits 57, 58, and 59 are all opened when an output is generated in AND circuit 35.

One input terminal of the AND circuit 35 is connected to the one-period selection circuit 30
The other input terminal is connected to the output terminal of the monostable multi-function 28.

Therefore, the AND circuit 35 operates for about 200 msec after the monostable multi 16 shown in FIG. A signal (processing end signal) is generated only during the period until the elapse of , that is, the period when the signal appears at the reset output terminal of the flip-flop 32, and each AND circuit 57, 58, 59 is opened.

More specifically, it is within the pulse width of the one-period pulse S6 that the leading value and the trailing value may actually occur as pulses to be determined.

This one-period pulse S6 is generated immediately after the waiting time of 200 msec generated by the monostable multi 16, that is, the monostable multi 2
occurs within the processing time made in 8.

Therefore, the AND circuits 57, 58, 59 operate during the remaining period of the 200 msec processing time excluding the period in which the one-period pulse 869 is occurring, that is, during the period in which the reset output signal of the main flip-flop 32 is occurring. The output signals of each flip-flop 53, 54, and 55 are prohibited from appearing outside, thereby eliminating the above-mentioned disadvantage.

As mentioned before, the output terminals of the flip-flops 53, 54, and 55 connected to the AND circuits 57, 58, and 59 are true coin sorting output terminals, so the other inverse output terminals are used to output coins other than those to be sorted. gives an output signal representing .

These output signals pass through an AND circuit 60 and an amplifier 61
After that, the sorting solenoid 62 is energized.

In this case, the AND circuit 60 is similarly configured to open when the AND circuit 35 outputs a processing end signal.

Further, the processing end signal output from the AND circuit 35 is amplified by the amplifier 63 and energizes the unmooring solenoid 64.

Therefore, at the same time an output is generated in the AND circuit 35, the solenoid 64 causes the stopper 5 of the coin passage of the coin sorting machine 1 to
is pulled against a spring (not shown), causing the coin 4 to fall from the position shown in FIG. , return the inserted coins to the return slot.

In the case of a true coin, the path switching plate is not activated and the input coin enters the coin separation mechanism.

Now, if the counter 44 overflows, it will immediately become 900.
When the th counter value is calculated, the AND circuit 29 is closed via the inverter 36, thereby resetting the flip-flops 32 and 33.

Therefore, the AND circuit 41 is closed and the input of the counter becomes zero.

This prevents the counter from malfunctioning.

The sorting device is thus ready to sort the input coins again.

Note that the portion S'14 remaining in front of the signal 814 shown at 14 in FIG. 3 does not actually affect the operation of the solenoid;
Since these solenoids are installed near the pressure sensor 7, integrating circuits etc. are provided in the amplifiers 61 and 63.
I'm jealous of how they prevent sled interference.

In the decoder 45 shown in the embodiment, the 1st, 10th, and 100th numbers are taken out from the three decimal decoders, and an AND circuit is used to read out only the necessary numerical codes.

Therefore, the width of the sorting natural vibration period can be arbitrarily changed later depending on the type of coin to be sorted.

Part or most of the coin sorting device described above can be made into an LSI.

In that case, it is advantageous to be able to change the connections of the decoder part.

As described above, according to the present invention, the phase of the oscillation circuit is automatically switched by the astable multiplier 17, and the oscillation circuit is locked to the side that meets the oscillation conditions, so that oscillation occurs reliably.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a sorting oscillation circuit and a coin vibration drive unit of a coin sorting device according to the present invention, and FIG. 2 is a block diagram of a coin vibration cycle sorting circuit of a coin sorting device using a sorting oscillation circuit according to the present invention. FIG. 3 is a time chart showing the operation of each part when the coin sorting device of FIG. 2 sorts coins with holes;
FIG. 4 is a drawing similar to FIG. 3 in the case of sorting non-perforated coins. 3... Inclined passage, 4... Coin, 5... Stopper,
6... Speaker, γ... Pressure sensitive sensor, 12... Light receiving element, 14.18, 23, 61.63... Amplifier,
15, 27... Schmitt trigger circuit, 16.28.
... Monostable multi-bi break, 17... Astable multi-bi break, 19.21... Gate, 20...
Phase inverter, 24.25... Rectifier circuit, 26, 29,
31, 35, 41... AND circuit, 3o... 1 period selection circuit, 40... Oscillator, 42, 43.44...
Counter, 45... Decoder, 46, 47.48...
・OR circuit, 50, 51.52 and 5γ, 58, 59,
6o...AND circuit, 32, 33, 53, 54, 55
...Flip-flop, 62.64...Electromagnetic cable/
Id.

Claims (1)

[Claims] 1. A speaker force and pressure-sensitive sensor provided in an inclined coin passage across the passage, a stopper that collides the inserted coin sliding in the passage and holds the inserted coin between the speaker and the pressure-sensitive sensor, and a speaker and a pressure-sensitive sensor. It has a positive feedback path connected in series with the pressure-sensitive sensor, and a mechanical filter consisting of the inserted coin, a subica, and the pressure-sensitive sensor is inserted into the feedback path, and the frequency is approximately the same as the mechanical natural frequency of the inserted coin. In a coin sorting device having a selective oscillation circuit that performs feedback amplification and oscillation at A selective oscillation circuit, characterized in that the magnitude of the output of the oscillation circuit is detected through a rectifier circuit, and when the value reaches a certain value, the astable multi-byte break is locked.