JPS6286960A - Tariff receiving telephone set - Google Patents

Abstract

PURPOSE:To detect unjust operation by providing a light emitting element inserted in series to a detection contact that operates responding to coins put in and closes a loop circuit and a light receiving element that receives emitted light of the light emitting element and gives dial transmission check information when loop current of the loop circuit is cut off. CONSTITUTION:A tone ringer 1 is connected in parallel between line terminals L1, L2 to which general subscriber circuits are connected through a capacitor C1 and a resistor R1, and thereby incoming is reported. Further, a hook-switch HS<1>, a contact ans<3> of a relay ANS, a contact CC1 as a coin detecting contact, a light emitting diode of a photo-coupler PC, a resistor R2, a diode D5, a contact ang<0>, and a switching circuit 2, a power source circuit 3 and a speaking circuit 4 including transmitter and receiver are connected through a diode bridge consisting of diodes D8-D11 between the line terminal L1, L2. When a coin is put in after making the hook switch HS<1> on by off-hook, the contact CC1 operates and closes a loop circuit via TKC 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a self-employed toll telephone that is connected to a general subscriber line and allows outgoing calls and telephone calls in accordance with the collection of charges.

[Conventional technology]

Such telephones determine the distance from the ground to the destination according to the dialed number, and charge the charges sequentially as the corresponding unit call time elapses. When storing coins, there is a need for a function that can detect unauthorized operations using string-hanging coins or the like and prevent dialing due to this.

For this reason, various countermeasures have been adopted in the past. The simplest and cheapest countermeasure is the CC1 contact, which detects coins that have been sorted and are waiting to be stored, and closes the loop circuit. It has been proposed to add a spring to the coin detection contact and use this additional spring contact to detect loop opening due to the absence of a coin after the loop is closed0 [Problems to be solved by the invention] However, CC1 If a spring is added to the contact point, it becomes difficult to operate the contact point reliably with a single coin, resulting in a problem of deterioration of reliability in practical use.

[Means for solving problems]

In order to solve the above-mentioned problem, the misfiring EA is constructed by the following means.

In other words, a light emitting element is inserted in series with a detection contact that operates according to the inserted coin and closes a loop circuit, and when the light emitted from this light emitting element is received and the loop current in the loop circuit is disconnected, a dial signal is sent. A light-receiving element that provides blocking information to a control circuit is provided.

[Effect]

Therefore, if the loop circuit is once closed and then opened due to unauthorized manipulation of a threaded coin, etc., the light emitted from the light emitting element will be dimmed, and the light receiving element will respond to this by transmitting the dialing prevention information to the control circuit. This prevents unauthorized dialing.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to a circuit diagram showing an embodiment.

In the figure, a tone ringer (hereinafter referred to as TRG) 1 is connected in parallel between line terminals L1 and 2 to which a general subscriber line is connected via a capacitor C1 and a resistor R1, and this notifies the incoming call. Furthermore, a hook switch I (S') is installed between line terminals L1 and L2.
, contact A1n53 of relay ANS, contact CC1 as a coin detection contact, light emitting diode of photocoupler pc',
Resistor R2, diode D5, contact ans°, and
Through a diode bridge made up of diodes D8 to D11, a switch circuit (hereinafter referred to as 5WC) 2, a power supply circuit (hereinafter referred to as PS) 3, and a communication circuit (including /'C1 handset)
Hereinafter, when the TKC) 4 is connected and a coin is inserted after turning on the hook switch H8' by off-hook, the contact CC1 is activated in response to this, and a loop circuit via the TKC 4 is closed.

Note that before the called party responds, a line voltage is applied to the line terminal L1 as a positive terminal, and when a loop current passes through the loop circuit in response to contact CC1 being turned on, a photocoupler inserted as a forward direction is applied to the line terminal L1. When the PCI's light emitting diode emits light, 5WC2 automatically turns on and allows loop current to flow. This loop current charges the capacitor in PS3, and supplies the terminal voltage of this to each part as the power supply VD. Become something.

In addition, a control circuit (hereinafter referred to as CNT) 5 consisting of a microprocessor, memory, etc. is provided, and in response to the power supply from the PS3, when the voltage of the power supply VD reaches a predetermined value, it performs an initial reset and then starts control operations. Then, when the dial key (hereinafter referred to as DK) 6 is operated according to the number of the other party, the CNT 5 controls the 5WC 2 and turns it off and on in accordance with the number operated on the DK 6. A dial pulse is sent out and a dial call is made in response to the operation of the DK6.

As a result, the exchange responds, an exchange connection is established, and when the called party answers, the exchange reverses the polarity of the applied line voltage, making the line terminal L2 positive, which also reverses the flow direction of the loop current. , the loop current blocked by diode D5 passes from terminal 1 to terminal 4 to response detection relay ANS via diode D6 and hook switch H8', and self-holding relay ANS
In addition to operating, self-preservation is performed.

In addition, 5WC2, PS3 and TKC4 are connected to diodes D8 to Dll! Regardless of the polarity of the line voltage, a loop current always flows in a fixed direction.

Depending on the operation and holding of the relay ANS, a contact anlI0 inserted to one side of the contact CC1, a contact ans'' inserted to the other side of the contact CC1, and a contact ans'
.

ans' respectively operate, contact ins' causes contact CC
While bypassing the diodes 1 to D5 and disconnecting them from the loop circuit, the contact ans3 connects the contact CC1 to CNT5 through the resistor R3, and the contact ins' connects the other side of the contact cci. Connect to the common circuit.

However, contact anB' is connected to the inverter (
Hereinafter, the power supply VD applied to the IN)70 input via the pull-up resistor r is connected to the common circuit, and this is set to "S" (low level), and the INγ output is set to "H" (high level). level) and then apply it to CNT 5 via resistor R4. If contact &nB' operates, the input of INV
In response to this output becoming rLJ, CNT5 recognizes the called party's response, starts determining the presence or absence of coins by contact CC1, and makes a unit call based on the number of the other party in response to the operation of DK6. The system calculates the time, monitors the call time using an internal timer, controls a coin storage circuit (not shown), and stores coins.

Therefore, the first coin is stored in response to the callee's response, but if there are any more waiting coins, contact CC1 is turned on and rLJ is applied to CNT5 via resistor R3.
According to this, the CNT 5 determines that the call should still be allowed.

On the other hand, when all the coins are stored, the contact CC1 is turned off, and "H" is applied by the power supply VD via the resistor r via the resistor R3, and in response to this, CNT5 is changed from the previous coin storage point to the unit CC1. During a call.

When the time has elapsed, the 5WC2 is controlled and turned off to forcibly disconnect the call.

Also, before the called person answers, use a string hanging coin etc.
Once contact CC1 is turned on, a local dial call is made, this is stored in CNT5, the exchange is restored and reacquired by turning contact CC1 off and on, and then contact CC1 is turned off and on again. If you perform unauthorized operations such as reversing and making long-distance calls, each contact ans
Before ~&n8' operates, the light emitting diode of the photocoupler PCI emits light in response to the flow of the loop current, and the light receiving transistor of the photocoupler PC1 receives the light and turns on, causing rLJ to flow through the resistor R3. However, if the loop current is cut off by turning off the contact CC1, the light receiving transistor turns off due to the dimming of the light emitting diode.
In order to apply rHJ through resistor R3, CNT5 receives this as dialing prevention information, determines unauthorized operation on the assumption that DK6 is not in operation, controls 5WC2 to turn it off, and restores the exchange. Disables subsequent dialing.

Note that the constant voltage diode ZD in parallel with the light emitting diode and the resistor R2 is provided to limit the voltage applied to the light emitting diode and the resistor R2 by Zener voltage, and to regulate the current flow value of the light emitting diode.

If the relay ANS goes on-hook after the end of the call, the line terminal L1 will be connected again when the exchange is restored.
becomes the positive terminal, so the hook switch H8' during restoration,
The relay ANS is energized from the terminal 4 to the terminal 1 through the operating contact ansffi and the diode Dγ, thereby restoring the system.

On the other hand, in the case of an incoming call, a 16H2 ringing signal with a DC component superimposed with the line terminal L2 as the positive terminal arrives, and if you go off-hook in response to the TRGI ringing, the diode D6 and hook switch H8 The current in the operating direction passes through the relay ANS, and the relay ANS
maintains the operation and bypasses the contact CC1 by the contact ans', so that answering calls can be made freely without inserting coins.

Therefore, contact CC1 closes the loop circuit in response to coin insertion, and after the called party answers, the waiting coin is detected. The contact CC1 can be used for both purposes.

In addition, a light-emitting diode is inserted in series with the contact CC1, and a light-receiving transistor that receives the light emitted from the light-emitting diode detects the disconnection of the loop current, and provides dialing prevention information to the CNT5. Therefore, while using the conventional contact CC1, Unauthorized operations can be reliably prevented.

However, other light-emitting elements may be used instead of the light-emitting diode, other light-receiving elements may be used instead of the light-receiving transistor, and the contact ins' is not particularly used for the common circuit connection of the contact CC1, The same effect can be obtained even if the photocoupler PCI side of the contact CC1 is connected to the common circuit using a high resistance value resistor or the like.

In addition, to obtain the power supply vn, the commercial power supply may be rectified and stabilized, and it can also be applied to the case of the forward loop method.
Various modifications are possible.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, unauthorized operation by a string-hanging coin, etc. can be detected without adding a special spring for the coin detection contact, and the simple and inexpensive configuration allows dialing based on unauthorized operation. Since outgoing calls can be reliably blocked, a remarkable effect can be obtained in various chargeable telephones.

[Brief explanation of drawings]

The figure is a circuit diagram showing an embodiment of the present invention. 2...SWC (switch circuit), No. 3...PS (
[source circuit), 4...TKC (communication circuit), 5...
・CNT (control circuit), 6...DK (dial key), Ll, Ll... line terminal, H8, H8@--
・Hook switch, ANS...Relay (response detection relay), ans'~ans3...Contact, CC1...
・・Contact (detection contact), PCl・φe・Photocuff "U, D5~D11...Fist・Diode, R1~R4...
·Resistor.

Claims (1)

[Claims] A light emitting element inserted in series with a detection contact that operates in response to an inserted coin to close a loop circuit, and a dial transmission block when the light emitted from the light emitting element is received and the loop current of the loop circuit is disconnected. What is claimed is: 1. A charge-storage telephone characterized by being equipped with a light-receiving element that provides information to a control circuit.