JPS6227955Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a coin passage monitoring device suitable for use in various coin processing devices.

[Conventional technology]

Conventionally, in a device such as a public telephone that performs a certain operation by inserting a coin, it is necessary to distinguish and sort whether or not the inserted coin is a specified genuine coin. , by focusing on the differences in the coin's material, outer diameter, etc., and converting it electrically.
Various magnetic sorting devices have been proposed. Since it is not known when coins will be inserted, these devices must be constantly powered on and in standby mode.
Power is always supplied during off-hook.

[Problem that the invention attempts to solve]

However, it is not desirable in terms of power consumption to keep such a coin sorting device in a constant standby state for coins that do not know when they will be inserted. This is especially inconvenient for public telephones that use central power supply and want to reduce power consumption as much as possible.
It is desirable to significantly reduce power consumption required for monitoring operations without reducing monitoring accuracy.

[Means for Solving the Problems] The coin passage monitoring device of the present invention has a light emitting element and a light receiving element placed opposite each other across a coin path, and a drive pulse with a small duty ratio is applied to the light emitting element at a constant cycle. and an output circuit that sends out a coin passage monitoring signal when the light-receiving element detects the passage of a coin, and a coin interrupts the period of the drive pulse between the light-emitting and light-receiving elements. The time is set to be one to several cycles.

〓〓〓〓〓
[Operation] When a coin passes between the light emitting and light receiving elements,
While the coin blocks the space between both elements, a driving pulse is supplied to the light emitting element at least once, and a coin passage monitoring signal is sent from the output circuit, but the driving pulse is supplied more than several times. Without a doubt,
Furthermore, since the duty ratio is small, the actual energization time is extremely short.

〔Example〕

FIG. 1 is a block diagram showing an embodiment in which the present invention is applied to a coin material sorting device. This example is an example when applied to a public telephone,
A local power source is used as the power source. In the figure, 10 is a public telephone circuit, 11 is a diode bridge circuit, 12 is a power supply circuit, 13a is a dial contact, 13b is a short-circuit contact, and 14 is a telephone call circuit. The power supply circuit 12 includes a power switch 15
When the power switch 15 receives the power signal i and is turned on, it supplies the power voltage V to the material selection circuit. Such a power signal i is generated in response to a coin passage monitoring signal sent from a coin passage monitoring section, which will be described later.

Note that the power supply circuit 12 is specifically configured as shown in FIG. 2, for example. In FIG. 2, 41 is a switch. In the on-hook state (the handset is put down, i.e. when there is no call),
Since the switch 41 is in the state shown in the figure, the voltage supplied from the exchange connected to the terminals L ₁ and L ₂ via the diode bridge circuit 11 is applied to the capacitor 44 via the high resistance 42 and the diode 43. A small current is applied to charge the battery. In this case, the Zener diode 45 is for stabilizing the voltage supplied to the capacitor 44. On the other hand, in an off-hook state (a state in which the handset is picked up, ie, in use), the hook switch 41 is connected in the opposite way as shown, so that the voltage supplied from the exchange side charges the capacitor 44 via the diode 46. together with diode 47
The capacitor 48 is charged via the capacitor 48. in this case,
Zener diode 49 stabilizes the voltage supplied to both capacitors 44 and 48. In this manner, since a voltage is generated in the capacitor 48 during off-hook, this voltage can be used for the material selection circuit. Note that a voltage is generated in the capacitor 44 regardless of whether it is on-hook or off-hook, and is used as a power source for something that requires a constant voltage supply, such as a RAM, for example.

Further, in FIG. 1, a diode bridge circuit 11 is used to keep the polarity of the voltage sent to the power supply circuit 12 constant regardless of the polarity of the DC voltage from the exchange. Furthermore, when the dial is turned, the dial contact 13a opens and closes the number of times corresponding to the number dialed, and sends and notifies the exchange of a dial signal indicating the subscriber number of the other party.
The short circuit contact 13b is closed at this time and the communication circuit 14 is closed.
to prevent the dial signal from affecting the communication circuit 14.

In FIG. 1, 16 is a stabilizing circuit that stabilizes the power supply voltage V, 17 is an oscillation circuit, and 18 is a detection coil. The detection coils 18 are arranged to face each other across the coin passage and are electromagnetically coupled to each other.
It consists of a pair of transmitting coil 18a and receiving coil 18b. The receiving coil 18b includes an amplifier circuit 19,
A rectifier circuit 20 and a comparison circuit 21 are connected to each other, and detect the output voltage of the receiving coil 18b, which changes depending on the magnetic permeability of the coin passing between both coils, and compare this with a reference value to obtain a comparison output e. Send out. On the other hand, an amplifier circuit 22, a rectifier circuit 23, and a comparison circuit 24 are connected to the transmitting coil 18a, and detect the eddy current loss caused by the coin, and compare it with a reference value to obtain a comparison output f. Send. These comparison outputs e and f are both input to the gate circuit 25, which determines the logic thereof and sends an output signal g to the monostable circuit 26. As a result, the discrimination signal h is obtained as the Q output of the monostable circuit 26.

In this case, if the inserted coin is a ferromagnetic material, there will be almost no signal induced in the receiving coil 18b, but the eddy current loss on the transmitting coil 18a side is also used as a detection element, and the logical outputs of both are detected. By using the discrimination signal h, it is possible to distinguish the materials of coins made of ferromagnetic materials such as iron and nickel.

There is a coin monitoring unit 27 that supplies the power supply voltage V to such a material selection circuit and controls the timing of outputting the discrimination signal h. As shown in FIG. 3, this coin currency monitoring section 27 is located above the detection coil 18 in the coin passage 50.
〓〓〓〓〓
1 arranged oppositely across the coin passage 50.
It has a photoelectric detector 28 consisting of a pair of light emitting element 28a and light receiving element 28b, and the light emitting element 2
When the coin 51 passes between 8a and the light receiving element 28b, a coin passage detection signal j is outputted as the Q output of the monostable circuit 29. Further, the light emitting element 28
A drive pulse generation circuit 30 is provided to drive the signal a. The drive pulse generation circuit 30 includes an oscillation circuit 31 that generates clock pulses, a binary counter 32, and a gate circuit 33, and as described later, a drive pulse signal a having a predetermined period and a small duty ratio is applied to the light emitting element. 28a and input to flip-flop 35 via inverter 34. flipflop 35
sends out a Q output signal c to the monostable circuit 29 and the gate circuit 25 by inputting the inverted output of the drive pulse signal a and the detection output of the light receiving element 28b. In response to this, the monostable circuit 29 sends an output signal d to the gate circuit 25 and the gate circuit 36. The gate circuit 36 receives the output signal d and the discrimination signal h, and sends an output signal at the L level to the power switch 15 as the power signal i when both inputs are at the L level.

Next, iron and nickel coins were selected.
When there are two types of genuine coins, both made of ferromagnetic material, to determine the authenticity and type of coins,
The operation of the coin material sorting device having the above configuration is as follows.
This will be explained using the time chart shown in the figure.

In FIG. 1, the drive pulse generation circuit 30 is
As mentioned above, the clock pulses generated by the oscillation circuit 31 are sent to the binary counter 32 and the gate circuit 3.
3 to generate a driving pulse signal a as shown in FIG. 4a, and send it to the light emitting element 28a. As shown in FIG. 4b, the period _T1 of this driving pulse signal a is determined by the period T1 between the light emitting element 28a and the light receiving element 28b when the inserted coin passes between the light emitting element 28a and the light receiving element 28b while rolling. The time T _{2 for blocking the optical path, that is, the time T 2 required} for the coin 51 to move from the solid line position to the broken line position in FIG. 3, is set to be one to several cycles. Further, the pulse width τ is extremely small, that is, in this example, it is set to 0.1 ms for the period _T1 of 3 ms so that the duty ratio is sufficiently small.
Therefore, the Q output signal c of flip-flop 35
As shown in FIG. 4c, after the coin begins to pass, that is, after it begins to block the space between the light emitting element 28a and the light receiving element 28b, it becomes H level when the first driving pulse is sent out, and the monostable circuit 29 is triggered. the result,
The output d of the monostable circuit 29 becomes L level as shown in FIG. 4d. At this time, the output signal g of the gate circuit 25 is at H level, and the Q of the monostable circuit 26 is
The discrimination signal h as an output remains at L level. Therefore, both inputs of the gate circuit 36 become L level, and as a result, the power supply signal i becomes L level and the power switch 15 is turned on, as shown in FIG. Supply begins. At the same time, the coin passage detection signal j as the Q output of the monostable circuit 29 becomes H level, confirming the passage of the coin.

In this way, when the coin 51 is inserted, it is detected that the coin 51 is inserted into the detection coil 1 that constitutes the material selection circuit.
8, the coin is detected by the coin passage monitoring section 27, and the power switch 1 is activated by the monitoring signal.
5 is turned on, and the power supply voltage V is supplied to the material selection circuit. Therefore, it is not necessary to keep the material selection circuit in a constant standby state. Furthermore, since the light emitting element 28a as the coin passage detection means is driven by a pulse with an extremely small duty ratio,
Power consumption can be further significantly reduced. In this case, the period T ₁ of the drive pulse signal a
As mentioned above, is the time during which a coin rolling in the coin passage blocks the space between the light emitting element 28a and the light receiving element 28b.
Since T ₂ is set to be one to several cycles, the coin will not pass between both elements while not a single pulse is being sent out, and the passage of the coin is certain. However, the pulse is generated only a few times at most, and the light emitting element is not operated more than necessary. That is, compared to the case where the monitor is kept in a constant monitoring state, power consumption can be significantly reduced by intermittent driving without reducing the monitoring accuracy at all.

Next, the coin is connected to the light emitting element 28a and the light receiving element 28b.
When the first drive pulse is sent out after passing between , the Q output signal c of the flip-flop 35 returns to the L level. During this time, the operation of the material selection circuit that was powered on first stabilizes.
A highly accurate sorting operation is now possible. Therefore,
〓〓〓〓〓
The coin 51 is connected to the transmitting coil 18a and the receiving coil 18b.
The material is sorted while rolling between the two. That is, when a coin passes between both coils, the receiving coil 18
The voltage induced in b changes. Therefore, this voltage output is amplified by an amplifier circuit 19, and the amplified output is rectified by a rectifier circuit 20, and the obtained DC voltage level is compared with a predetermined reference voltage level band by a comparator circuit 21. In this case, if the coin is made of a material with low magnetic permeability such as copper or lead, a relatively large induced voltage will be obtained in the receiving coil 18b, but if the material is made of a ferromagnetic material such as iron or nickel. There is almost no induced voltage mentioned above. As a result,
In the former case, the comparison output e remains at H level, whereas in the latter case, it becomes L level as shown in FIG. 4e. Therefore, by using this comparison output e, counterfeit coins made of non-ferromagnetic materials can be excluded.

On the other hand, the output taken from the transmitter coil 18a changes due to eddy current losses. Therefore, this voltage output is amplified by an amplifier circuit 22, this amplified output is rectified by a rectifier circuit 23, and the obtained DC voltage level is compared with a predetermined reference voltage level band by a comparison circuit 24. In this case, if the material of the inserted coin is iron, the eddy current loss is large, so a relatively large output can be obtained from the transmitting coil 18a, whereas if the coin is made of nickel, only a small output can be obtained. . As a result, in the former case, the comparison output f maintains the H level, whereas in the latter case, it becomes the L level as shown in FIG. 4f. Note that the comparison output f is also at the H level when the coin is made of copper, lead, or the like.

Therefore, only when the coin is a nickel, both comparison output e and comparison output f become L level. During this time, the Q output signal c of the flip-flop 35 and the output signal d of the monostable circuit 29 are both low.
level, all four inputs of the gate circuit 25 are at the L level, and as a result, the output signal g is at the fourth
As shown in Figure g, it becomes L level. As a result, the discrimination signal h as the Q output of the monostable circuit 26 is
As shown in Figure h, the level is H, and it can be determined that the inserted coin is a genuine coin made of nickel. At the same time, this H level discrimination signal h is applied to the gate circuit 3.
As a result, the power signal i becomes H level, the power switch 15 is cut off, the supply of power voltage to the material selection circuit is stopped, and the selection operation is completed. The Q output as the coin passage detection signal j and the output signal d of the monostable circuit 29 automatically return to their original states after a certain period of time has elapsed.

The reference level bands of the comparison circuits 21 and 24 are both set to the level band with the best resolution, and when a predetermined coin is inserted, the input level of each comparison circuit 21 and 24 becomes the corresponding level. The amplifier circuit 19,
The gain of 22 is adjusted. However, the amplifier circuit 22 mainly functions only as a matching circuit, and its gain is usually less than 1.

In this way, the power switch 15 is automatically turned off when the output of the discrimination signal h starts, and the supply of power voltage to the material selection circuit is cut off, so power consumption can be kept to the necessary minimum. .

Further, after the output signal d of the monostable circuit 29 becomes L level and the power switch 15 of the material selection circuit is turned on, after the coin has passed between the light emitting element 28a and the light receiving element 28b, The first drive pulse is sent and the Q of flip-flop 35 is
Until the output signal c reaches the L level, regardless of the levels of the comparison outputs e and f of the material selection circuit,
The output signal g of the gate circuit 25 becomes L level,
The H level discrimination signal h is never output.
The reason why a certain time interval is set between the power-on and the transmission of the H-level discrimination signal h is to take into account the transient state immediately after the power is turned on. That is, the operation of the material sorting circuit is sufficiently stabilized during this prohibition time, and as a result, after the first driving pulse is sent and the prohibition is canceled, the coin is not transferred between the transmitting coil 18a and the receiving coil 18b. The sorting operation when passing through is performed accurately.

[Effect of the invention]

As explained above, according to the present invention, in the coin processing device, only the coin passage monitoring device according to the present invention is operated at all times, and other various sorting devices, etc., receive coins from the output circuit of the coin passage monitoring device. By supplying power only when a signal indicating passage is sent, it is possible to significantly reduce power consumption during standby. In addition, the coin passage monitoring device according to the present invention sets the driving cycle so that the time during which the coin interrupts the light emitting element and the light receiving element is one to several cycles, and also uses pulses with a small duty ratio.
By driving the sensor with 200 MHz, the power consumption of the sensor itself can be extremely low while preventing a drop in monitoring accuracy. In particular, the present invention is extremely useful for public telephones using a central power supply system in which it is desired to suppress power consumption as much as possible.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention.
FIG. 2 is a circuit diagram showing a specific example of the configuration of the power supply circuit.
FIG. 3 is an explanatory diagram showing the arrangement of a detection coil and a photoelectric detector, and FIG. 4 is a time chart of each output pulse of the coin passage monitoring device shown in FIG. 1. 27... Coin passage monitoring unit, 28... Photoelectric detector, 28a... Light receiving element, 28b... Light receiving element,
29... Monostable circuit, 30... Drive pulse generation circuit, 31... Oscillation circuit, 32... Binary counter,
33...Gate circuit, 34...Inverter, 35
...Flip Flop, 50...Coin aisle, 51
……coin. 〓〓〓〓〓

Claims (1)

[Scope of utility model registration request] a photoelectric detector consisting of a light emitting element and a light receiving element arranged oppositely across a coin passage; a pulse generating circuit that supplies a drive pulse with a small duty ratio to the light emitting element at a constant cycle; and an output circuit that outputs a coin passage monitoring signal when passage is detected, and the period of the drive pulse generated by the pulse generating circuit is adjusted so that the coin passes between the light emitting element and the light receiving element when the coin passes. A coin passage monitoring device characterized in that the interruption time is set to correspond to one or several cycles.