JPS5816832B2 - Coin storage confirmation device in public telephones - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for monitoring the insertion and storage of coins into a public telephone.

Public telephones allow calls to be made by inserting coins, and are retractable after the charge, i.e., after the call ends or after a certain call time has elapsed, the coins are inserted and waiting in line based on the billing signal from the exchange. In a system in which coins are stored one by one in a charge storage safe by operating a storage lever, the coins must be in a standby position immediately before dialing, and it is necessary to detect this.

On the other hand, if a coin is stored in response to a billing signal, the coin disappears from the standby position, so it is necessary to detect this, but conventionally, the coin in the standby position is detected and then the storage operation is performed. This means that the coin is considered to have been stored, and if the coin stops at the standby position for some reason, this cannot be detected.

Conventionally, as a coin detection means, a mechanical contact operated by the coin's own weight or an interposition, or a reed switch driven by a magnet displaced by the coin's own weight has been used.

However, these methods are difficult to adjust, and can only be used when polarity inversion signals are used as billing signals, and cannot be applied to billing signals that use alternating current signals.
Moreover, it has drawbacks such as being susceptible to chuckling and cannot be used as is as an input to an electronic control circuit.Recently, coin monitors using a light emitting element and a light receiving element have been proposed.

However, since light-emitting elements require a large amount of power, when constantly monitoring coins like conventional mechanical contacts, it is not possible to use the line current from the exchange or the voltage between the lines as a power source due to power consumption. However, since it required a separate power source, it was extremely unsuitable for use in public telephones, and there were many obstacles to putting it into practical use.

In order to solve all of the above-mentioned drawbacks and problems of the conventional technology at once, the present invention aims to realize lower power consumption and higher reliability in checking the coin storage status, and has a part that holds the coin path of a public telephone. A coin monitor including a light emitting element and a light receiving element that receives the light emitted from the light emitting element facing each other is provided above the storage lever in the middle of the coin path, and
A signal generating circuit generates a signal synchronized with the leading edge and trailing edge of the charge signal, and the light emitting element of the coin monitor is instantaneously driven open by the synchronized signal.

The coin monitor includes a drive circuit and a gate circuit that individually gates the output obtained from the light receiving element of the coin monitor using a signal synchronized with the leading edge and the trailing edge, and confirms the coin storage status based on the billing signal. The present invention provides a highly reliable coin monitoring system that is extremely rational and has low power consumption, can be used in exchanges that use tone signals as billing signals, and is easy to manufacture.

Hereinafter, the present invention will be described in detail with reference to figures showing embodiments, and each circuit will also be described because it is related to other circuits.

Figure 1 is a cross-sectional view of the coin path in a public telephone;
A coin inserted from above the coin path 1 made of a flat metal tube or the like is concentrated by the storage lever 2 and waits directly above the storage lever 2. However, when a billing signal arrives from the exchanger, the coin is inserted into the storage lever 2. is the lever 4 centered on the fulcrum 3.
The shift causes the coin to slide to the right and drop the waiting coin into the storage safe below, and the inward protrusion of the stopper 5 prevents coins that are above the waiting coin from falling, ensuring that the coin is Assume that only one coin is dropped.

Therefore, immediately before a call is made from the telephone, it is necessary that a coin be present in the standby position, that is, directly above the storage lever 2, and at the same time, there must be no coins present directly below the storage lever 2. Both conditions must be met. For the purpose of checking, the light emitting elements EL, EL2 such as light emitting diodes and the light receiving elements PT1 . PT2 are provided facing each other, and the light beams emitted by the light emitting elements EL, , EL2 are directed to the light receiving elements PT1. PT, , are in the relationship of receiving light, and depending on the presence of a coin, the light receiving element p'r1゜P
The light receiving input of T2 is cut off, and the light receiving elements PT, , PT2
The impedance of PT rises, that is, becomes an OFF state, and the absence of a coin provides a light receiving input, and the light receiving elements PT,...
The impedance of PT2 decreases, that is, it becomes on-state, and coin detection at each position is performed based on this impedance change.

FIG. 2 is a circuit diagram showing the configuration of a control circuit to which this method is applied, in which a hook switch H3 and a dial impulse contact Di are inserted in series between the line terminal L2 and the telephone communication device. Furthermore, in order to prevent the intermittent sound of the current caused by the impulse contact D1 during dialing from being applied to the calling device, a shortening contact D of the dial is used to shorten the calling device.
s is connected in parallel with the telephone call device, and the shorting point Ds is turned on from the phase change of the dial until the end of the phase change.

The light-emitting element EIJ in FIG. 1 is inserted in series between the short-circuit contact Ds and the communication circuits TE and L in the column parallel to this short-circuit contact Ds, that is, the light-emitting element EIJ in FIG. When turned on, a loop current between the line terminal Lly L2 and the communication device emits light, and a light beam resulting from this light emission is received by the light receiving element supply PT2.

Note that the light receiving element PT2 is the same as that in FIG. 1, and the other light emitting elements EL1. The light-receiving element PT1 shown in FIG. 1 is also used.

Therefore, the loop current due to hook-off is
While the light is connected to L2, the light receiving element PT2 is on, and the voltage at the connection point with the resistor R7 is low potential (hereinafter referred to as ?+L +1), but the shorting contact Ds is turned on due to the phase change of the dial. Then, the light emitting element EL2 and subsequent elements are short-circuited, and the light emitted from the element EL2 disappears, the light receiving element PT2 is turned off, and the voltage pt2 becomes a high potential (hereinafter referred to as "H") almost equal to the voltage V.

G<Well, assuming that coins are staying between the light-emitting element EL2 and the light-receiving element PT2 in FIG.
The hook switch H8 in the figure is turned on, and the loop current causes the light emitting element EL2 to emit light, but the light receiving element PT
Since the voltage pt2 remains off and the voltage pt2 is H'', this is applied to the input 1 of the NAND gate 1-NANDl.

On the other hand, the diode D1. D2, Zener diode ZD
1 and the capacitor C1 are used to power each circuit using the line voltage from the exchanger, which is applied between the line terminals L1 and L2 with the line terminal L1 as the positive terminal.
The terminal voltage of the capacitor C1 is taken out from the terminal V and supplied to each circuit, and the loop current generates a voltage at the terminal V. Upon receiving this voltage, the initial reset circuit IR8 using a differentiating circuit etc. outputs continuous output and pulse output. is generated as "H", and the pulse output is given to the input 2 of the NAND gate NAND1.

Therefore, the output of the NAND gate NAND is "L".
This L'' is inverted by inverter 1N2,
The signal becomes "H" and is applied to the input 1 of the NOR gate N0R1, making its output "L".

By this L'', a flip-flop circuit (hereinafter referred to as FFC)
) FF1 is set, and its output "L" turns on the transistor Tr4 through the diode D3 and the resistor R12, and the semiconductor element SCR in parallel with the impulse contact Di.
Turn on to prevent dialing.

That is, for the impulse contact Di, a semiconductor element SCR such as a cyrisk having a gate terminal as a control float is used.
is inserted, and a capacitor C4 and a resistor R3 for gate pulse application are connected to this gate terminal.
Further, a transistor Tr5 is connected to this circuit, and when the transistor Tr5 is turned on, the semiconductor element SCR is turned on.
The direction is now turned eastward.

Note that if there is no coin staying between the light emitting element EL2 and the light receiving element PT2, the light receiving element PT2 is turned on, so that the voltage V
pt2 is L'', and the above-mentioned shorting of the impulse contact Di is not performed.

Also, when the coin is suspended in the standby position between the light emitting element EL1 and the light receiving element PT in FIG.
A short circuit of i is performed.

That is, as mentioned above, when the initial reset circuit IR8 generates a pulse-like output "Hjl" due to hook-off, this is applied to the input 4 of the NOR gate N0R2 and the output becomes "L", so when this is inverted by the inverter IN6, " H19, which is the capacitor C9,
It is differentiated by resistor R19 to become a differential pulse, and is inverted by inverter N7 to become "LH".
The transistor Tr6 is turned on only during this differential pulse.

As a result, the light emitting element E L is connected via the resistor R115.
1, and the element EL emits light; however, due to the presence of the coin, there is no light reception input to the light receiving element PT1, and the resistor 1 (i
The voltage Vpt1 at the connection point with a remains "H", therefore, the input 1 of the AND gate AND1 is 3 ft
At the same time, the output of the input 2 initial reset circuit IR8 of the same gate AND is given as "H", so the output of the AND gate AND1 becomes "H", which is NOR/7'-to-NOR3. It is applied to input 1 of , and its output is set to "L".

This results in two inputs (+?
When it changes to "L", the output of the gate NOR3 is "L" as well as the base of the transistor Tr6, so the output of the same gate NOR3 is
This becomes "H" and is applied to the input 2 of NOR1 (NOR game), and the output of the same game -1-NOR1 is set to "L", and the FFC
- In order to set FF1, the semiconductor element S
CR turns on and short-circuits impulse Di.

Then, there was no coin on the light emitting element EL2 side, and the light emitting element EL
When the dial is rotated in a state where there is no coin waiting between 1 and the light receiving element PT1, the light emitting element EL2 dims due to the short circuit contact Ds being turned on, and the light receiving element PT2 is turned off, so that the voltage vpt2 (" This change is differentiated by the capacitor C6 and the resistor R13, and a pulse signal is given to the inverter N3, and the inverted output "L" is applied to the resistor R1.
The transistor Tr6 is turned on via the transistor Tr4.

When the light emitting element EL1 emits light by turning on the transistor Tr6, the light receiving element PT1 receives the light and changes the voltage Vpt1 to 'L'', thereby setting FFC-FF2. Therefore, the output turns on the transistor Tr4, and the semiconductor element SCR is also turned on and impulse contact D
Short-circuit i and make it impossible to make a call.

Note that the light emitting element EL1 emits light only during the period of the pulse signal from the capacitor C6 and the resistor R13, and this check is made at the same time as the start of dial phase rotation, and the light emitting element EL
If there is a coin on the 1 side, FFC-FF2 will not be set and dialing will be possible.

In addition, since the shorting contact Ds is turned off by the end of the rotation of the dial, the voltage Vpt2 changes to L'', which causes F
FC-FF2 is reset, but FFC-FF1 is hooked off after performing hook-on once.) Only then does the initial reset circuit IR8 give a reset pulse, so it maintains the set state and dials until it hooks up again. prevent.

As described above, the presence or absence of a coin at a predetermined position is checked before the dial phase change and at the same time as the phase change starts, but a recheck is also performed during the dial rotation as described below.

First, when the hook switch H8 is turned on due to hook-off, the Zener voltage Vz1 of the Zener diode ZD
capacitor C1 is charged, and the voltage is applied to resistor R
g p applied to Rg and Zener diode ZD2, but Zener diode ZD.

Since the Zener voltage Vz2 is higher than vzl, the Zener diode ZD2 maintains the off state.

However, when the impulse contact Di of the dial is turned off by operating the dial, the line voltage between the line terminals and R2 is applied to the Zener diode ZD2, turning it on, causing the connection point between resistors R8 and R9 to become "L". This is inverted by the inverter IN1 and set to H, and the capacitor C6 is charged by a charging circuit consisting of a diode D6 and a resistor R11.

However, the time constant of this charging circuit and capacitor C6 is approximately equal to the normal off time of the dial pulse.

Furthermore, when the impulse contact Di turns on, the Zener diode ZD2 turns off again, setting the input of the inverter IN1 to "H", and the output is transferred to "LII", so that the output impedance of the resistor R1o and the inverter IN1 The electric charge of the capacitor C3 is discharged by the discharge circuit.

Note that the resistance value of resistors RIO and R11 is R10>R
11, and since the time constant of the discharging circuit and capacitor C5 is larger than that of the charging circuit, the terminal voltage of capacitor C6 reaches "Hll" immediately after the start of dial dispersion, and this is applied to the AND gate. AND2 input 2 and NOR
It is applied to input 3 of gate N0R2.

As a result, the output of the NOR gate N0R2 becomes "L", turning on the transistor Tr6 and causing the light emitting element EL to emit light as described above. Therefore, the voltage Vpt1 force f
The signal becomes "L" and is inverted by the inverter IN4 to become "H" and then applied to the input 1 of the AND gate AND.

At this time, the input 2 of the gate AND2 is also connected to the capacitor C.
5 "H" is given, and the output of the same gate AND2 becomes H'' and the NOR gate NOR
3, and the output of the same gate NOR3.
L? 1, FFC-FF1 is set via the NOR gates NOR, , NOR, and the transistor Tr4 is turned on in the same manner as described above, and the semiconductor element SCR is turned on to prevent dialing.

Note that if there is a coin next to the light emitting element EL, the light receiving element PT
1 remains off, and the voltage Vpt1 is 'H', so F
FC-Ff'1 is not set and dialing becomes possible.

As mentioned above, the presence of coins is checked during dialing, but in addition to this, a check is also made to see if the coin is in the specified position when the coin is stored when a billing signal arrives from the exchange. If so, the call circuit is forcibly disconnected.

That is, line terminal L1. The transistor T r 1 as a switching element inserted in series between L2 and the communication device operates as a disconnection circuit, and when the hook switch H8 is turned on by hook-off, the line terminal L1. At the same time, the line voltage between L2 is applied, and the transistor T r 2 connected to the base as a control terminal of the transistor T r 1 is forward biased by the resistor R2 and turned on, so that the transistor Tr 2 is turned on.
1 is also turned on and maintains this state.

Note that line terminal L1. by dial impulse. When the DC loop between L2 is cut off, the transistor Tr1 is kept in an on state by the charge of the capacitor C2 via the resistor R1.

In this state, a dial call is made and after the call starts, 16K
When a billing signal in the form of a tone signal such as Hz arrives, a billing signal receiving circuit PSR using a filter, an amplification detector, etc.
produces an "H" output between the start and end of reception, and capacitor C7 and resistor R1 differentiate the start of reception, synchronizing a relatively long-width differentiated pulse with the leading edge of the billing signal. H as a signal to input 2 of NOR gate N0R2
At the same time as given as 94, ANI) game 1 - AND 4
It is also given to input 2 of .

Therefore, until now all the inputs were "L" 91, so the output was "H"
The output of NOR gate N0R2, which was jt, becomes “L t
l, and the inverter IN6. Gondensa C
9. ``L t via resistor RIQ and inverter IN7
The differential pulse at t is applied to the transistor T r 6, causing the light emitting element EL to emit instantaneous light.

At this time, if there is no coin, the light receiving element PT is turned on and the inverter IN4 is turned on to set the voltage Vpt1 to L''.
The output of is changed to H'' and is applied to input 1 of AND game 1-AND4.

Then, the differential pulse from the aforementioned σ: capacitor C7 and resistor R1□ is given as "Hn" to the input 2 of the same gate AND4, so the output of the same gate AND4 becomes "Hll", which is NORed. Apply it to the input 2 of the gate N0R4, and set the output of the gate N0R4 as LI+,
The input 2 of the NOR gate N0R6 is given Ln along with the base of the transistor 1r6 to the input 1.
L+, the output is changed to T Hy'', drives a pulse generator PG such as a monostable multi-bi break, generates a pulse output H'' with a time width sufficient to restore the exchange, and resistor R3. The control transistor Tr3 is turned on via the control transistor Tr3.

Then, the transistor Tr2 is turned off because the emitter and base are short-circuited, and the transistor Trl is also turned off, forcibly cutting off the communication circuit during the above-mentioned signal output period, and making the communication less important. do.

However, if there is a coin next to the light emitting element EL, Vptl will be “
The line remains at "H", and this disconnection is not performed and the communication state is maintained.

In addition, the output of the billing signal receiving circuit PSR operates the coin storage magnet (not shown in the diagram) that shifts the lever 4 in FIG. Ru.

Next, when the charging signal ends, the charging signal receiving circuit PSR
Since the output disappears and the coin storage muck net etc. is restored, the next coin held by the stopper 5 falls to the standby position and is stopped by the protruding storage lever 2 again.

however. Since it takes some time for the next coin to reach the waiting position, we check to make sure there are no coins immediately after the charging signal ends, and confirm whether the waiting coins have been completely stored. .

For this purpose, an inverter IN5, a capacitor C8, and a resistor R18 are provided, and when the charging signal ends, the reception output of the charging signal receiving circuit PSR disappears.
At the point when it changes to L +1, it becomes H″ due to impark IN5.
In addition, it is converted into a differential pulse by capacitor C8 and resistor R18, and this differential pulse is designated as "Hll" by AN
Input 2 of D gate-1-AND3 and NOR gate N0
It is applied to input 1 of R2 as a signal synchronized with the trailing edge of the billing signal.

Therefore, the output of the NOR gate N0R2 becomes °L'', turning on the transistor Tr6 in the same way as described above, and causing the light emitting element EL□ to emit light only for an instant.At this time, if there is a coin, it will not receive light. Since the element PT1 remains off and the voltage V p t 1 remains at H'', which is applied to the input 1 of the AND gate AND3, the differential pulse of the input 2 causes the output of the gate AND, . H91, and drives the pulse generator PG via the NOR gates N0R4 and N0R6 in the same manner as described above, and the transistor T
Turn r1 off.

However, if there is no coin near the light emitting element EL, the light receiving element is turned on and the voltage Vpt1 becomes Ll+, so the transistor Trl is not turned off and the communication state is maintained.

Note that regular dialing should be performed after a dial tone is sent from the exchange, and the circuit shown in Figure 3 is provided to check this, and the circuits shown in Figure 2, which are indicated by the same numbers, are interconnected.

That is, dial tone receiving circuit DTR connects line terminal L1. The output of the frequency selection element FL using a high input impedance filter etc. bridge-connected between L2 is amplified by the amplifier A, and then converted into a pulse signal with a period corresponding to the frequency of the dial tone in the waveform shaping circuit WF. and
This is applied to input 1 of OR gates 0R4t and 0R12.

- On the other hand, the phase change of the dial turns on the short-circuit contact Ds, so as mentioned above, the light receiving element PT2 turns off and the voltage v
Transfer pt2 to ff H91.

This σH” is passed through the jump signal ■ to the NAND gate NAND1
Since the input 1 of the same game 1-NANDll is "Htj" due to the resistor R22,
Same gate NAND1. Converts the output to “L” and sets it to 0.
It is applied to input 3 of R11 to turn on the gate 0R11.

Then, the pulse signal from the dial tone receiving circuit DTR passes through the OR gate OR1, and the first pulse drives the pulse generator PG2, such as a monostable multi-bibreak, to start a specified period for counting the dial tone pulse signal. A pulse output of L'' having a time width T is generated for regulation.

At the start of this pulse output, the capacitor C2□ is instantaneously discharged, and only during this period is the NAND date NAND1. In order to set input 1 to "L 91", the same gate NAND, □
The output of is momentarily changed to "Hll", thereby resetting the counter CT.

On the other hand, the aforementioned pulse output is OR gate OR1□C input 2
is also given to the same gate t-O to set it as "L'".
The pulse signal given to input 1 can pass through R1□, and the pulse signal of the dial tone passes through the OR gate 0R12 only during a period of 1 time width T, which is counted by the counter CT1 and corresponds to the frequency of the dial tone. When counting the number of pulse signals, outputs B1 to B3 are set to H" at the same time only when the count is completed, and NAND/7" is output.
- Inverter ■N1 with the output of NAND1 as “L”
2 to H” through NAND gate NAND13
Give it to input 2 of

At this time, when the pulse output with the time width T ends and changes to "H", the output of the NAND gate NAND1 becomes "L", thereby resetting the FFC-FF3, and the output from the initial reset circuit IR8 sets it to the set state. The output of
r4, the transistor Tr4 is turned off, the on state of the semiconductor element SCR is changed to the off state, and dialing is enabled.

That is, if inputs 1 and 2 of the NAND gate NAND 1s become "H" at the same time, the output becomes "L - 1", and it is detected that a regular dial tone has arrived at the time of dial phase change. .

Note that if the dial tone is not a regular dial tone but has a different frequency, the outputs B1 to B3 of the counter CT1 will be 1 at the same time.
NA due to the timing of becoming H'' and the end of pulse output.
The input 1 of the ND gate NAND12 does not match the timing of switching to "H2S" and no detection output is generated, thereby preventing FFC-FF3 from being reset and preventing dialing.

In addition, the output of the NAND gate NAND1□ resets the counter CT2, and the output of the above-mentioned Zener diode ZD2
The counter CT2 counts the number of dial pulses generated by the dial scattering, even if it corresponds to a prohibited number such as "0". Counting output B2. B and NAND gate NA are set to "H" at the same time.
The output of ND14 is set as *L u, and this is given to the pulse generator PG1 to drive it, and the transistor Trl of the disconnection circuit is
turns off, forcibly disconnects the circuit and prevents transmission.

When the dial rotation is completed, the light emitting element EL2 emits light due to the shorting contact Ds being turned off, and the light receiving element PT2 is turned on. By setting the voltage vpt2 to ffLtt, the output of the NAND gate NAND1□ becomes "H". ”, the counter CT1 is reset, and its outputs B1 to B3
are all set to "L", the output of the NAND gate NAND12 becomes "H", and the counter CT2 is also reset.

In addition, when counter CT1 counts a specified number of times and detects a regular dial tone, inverter 1N1
The output of 2 makes the input 2 of OR gate 40R11 “H”.
', the gate 0R11 is set in a state where it cannot pass, and the pulse generator PG22 is prevented from being driven again by the dial tone pulse signal, but the pulse output of the six-pulse generator PG2 ends before counting the specified number. , When a regular dial tone cannot be detected, "H" due to the end of pulse output is impark IN, 1 is inverted and "L t
t, the charge in the capacitor C2□ is discharged through the resistor R2□ and the output impedance of the inverter N11, and after a certain period of time, the input 4 of the OR gate 0R11 is changed to "L", and the gate OR1, is in the passing state, and the pulse generator P is activated by the pulse signal of the dial tone.
After re-driving G2, the counter CT1 is caused to perform the counting operation again.

Note that the above circuit configuration can be modified in various ways depending on the characteristics of the logic circuit used, and it goes without saying that any combination can be used depending on the conditions.

As is clear from the above explanation, according to the present invention, since the coin monitor is activated only when it is needed, the power consumption is low and the power supply from the exchange is sufficient, and at the same time, the billing signal using the tone signal is Based on this method, the storage status of coins can be reliably monitored, and furthermore, it is easy to downsize and manufacture by using all semiconductors, so it has great effects in public telephones.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a sectional view of a coin path, FIG. 2 is a circuit diagram showing the configuration of a control circuit, and FIG. 3 is a block diagram of a dial tone detection circuit. 1... Coin path, 2... Storage lever,
E.L. EL2... Light emitting element, PT, , PT2...
・・・・Light receiving element, Ll, L2・・・・Line terminal,
Placement...One call circuit, H'S...Hook switch, Di...Impulse contact, Ds...
... Short circuit contact, Tr1 to Tr6... transistor,
SCR...Semiconductor element, ZDl, Zn2...
...Zener diode, PSR...Charging signal receiving circuit, PG, , PG2...Pulse generator, FF1-FF2...FFC (flip-flop circuit), IR8 ...Initial reset circuit, IN1 to IN7.1N11 to 1N14...
・・Inverter, NANDl, NANDl, ~NAND
1.・・・・・・NAND gate, N0R1~N
0R6...NOR gate, AND, ~AND
4...AND gate 0R11, 0R12...
...OR gate, CT1, CT,...
····counter.

Claims (1)

[Claims] 1. A coin monitoring device in which a light-emitting element and a light-receiving element that receives the light emitted from the light-emitting element are installed facing each other in a part sandwiching the upper part of the storage lever in the coin path of the public telephone, and the front and rear edges of the charging signal. a signal generation circuit that generates a signal synchronized with the leading edge and the trailing edge; a drive circuit that instantaneously drives a light emitting element of the coin monitor to open with a signal synchronized with the leading edge and the trailing edge; and a light receiving element of the coin monitor. a gate circuit that gates the output obtained from the leading edge and the trailing edge individually by a signal synchronized with the leading edge and the trailing edge, and the coin storage is confirmed by the output of the gate circuit. Coin storage confirmation device.