JPH0115251Y2 - - Google Patents

Description

[Detailed explanation of the idea]

This invention relates to a public telephone that can be used even when the commercial power supply is on or during a power outage, and can switch between 10 and 20 yen rates.In particular, it controls the reminder sound oscillation circuit that generates the reminder sound for inserting coins. The present invention relates to a reminder sound control device for a public telephone set. Generally, in public telephones, when the called party responds, the in-office equipment sends out a polarity reversal pulse (charging signal) as a coin storage signal after cutting off the communication current, and the telephone side receives this and operates a coin storage relay. Accordingly, the coins stored in advance are stored one by one in the safe. When the last coin that has been delivered in advance is stored during a call, the oscillator inside the phone generates a sound (for example, around 250 Hz) reminding the user to insert the coin, and the accumulated coins run out. , is configured to notify you that there is only one call time left. The basic configuration _of the reminder sound control device used in conventional general public telephones will be explained with reference to _FIG . A hook switch that operates when the handset is raised and remains in operation until it is returned, CCL is a contact for detecting coin insertion, L ₀ is a part of the induction coil that forms the sidetone prevention circuit, T is the transmitter,
R is a receiver. P is activated by a polarity reversal pulse sent from the station equipment, and is restored by the loop of the office line terminal L ₁ (+) after the end of this polarity reversal pulse, and also by returning the handset. The coin storage relay to be restored, CC ₁ , monitors the presence or absence of the first coin among the coins previously stored in the coin storage mechanism. That is, the first coin operated
The contact point is connected between the relay P and the induction coil L ₀ . Similarly to the first contact CC ₁ , CC ₂ is a second contact that monitors the presence or absence of a second coin among the accumulated coins, that is, it is operated by a coin, and is a reminder sound oscillation circuit that generates a reminder sound. Connected in parallel with the TG terminals. The anode side of Th is connected to one end of the coin storage relay P, the cathode side is connected to one end of the reminder sound oscillation circuit TG, and the gate is connected to the resistor.
A thyristor element is connected to the connection point between resistor R ₁ and resistor R 2 of a series circuit having R _{1 ,} R ₂ and diode D ₁ , and a polarity reversal pulse is transmitted to central line terminal L _2.
(+) and the station line terminal L ₁ (-), it is configured to conduct by a drive signal created by the series circuit. Note that D ₁ and D ₈ are diodes for detecting the current direction. In the reminder sound control device configured in this way, when the handset is raised to make a call and multiple coins are inserted into a coin storage mechanism (not shown), the hook switch HS, the coin insertion sensing contact CCL, and the first contact
CC ₁ and the second contact CC ₂ are closed, and the coin storage relay P is operated by the polarity reversal pulse that arrives from the station side at the same time as the called party's response to store the coin, and the diode D ₁ and the resistor The thyristor element Th becomes conductive due to the drive signal formed by the series circuit of R ₁ and the resistor R ₂ , but since the second contact CC ₂ is closed, the reminder sound oscillation circuit TG is short-circuited. Therefore, no driving voltage is supplied and no reminder sound is generated. However, if the polarity reversal pulse arrives when the second contact CC ₂ is open, that is, when only one coin is accumulated in the coin storage mechanism,
Since the first contact CC ₁ is closed, the thyristor element Th becomes conductive in the same way as above, and the reminder sound oscillator
A predetermined voltage is supplied to the TG, and the oscillator TG generates a reminder tone and calls the user's handset R.
It informs you that you have run out of coins and can only talk for one more time. On the other hand, public telephones need to be able to update the charge per call in preparation for future rate changes, and generally there are phones that can be switched to charge 10 or 20 yen per call. Proposed. However, when changing from storing one 10 yen coin to storing two coins, for example, in a central power supply type public telephone, a third contact CC ₃ must be provided at the fourth coin position, or a second It is necessary to relocate the contacts to form a control circuit for the reminder sound and a control circuit for the DC loop, resulting in a problem that the circuit configuration becomes complicated and uneconomical. On the other hand, public telephones that use commercial power and have a central control circuit count the accumulated coins and perform DC loop control and reminder sound control based on the accumulated coins, which simplifies the circuit configuration, but does not stop service in the event of a power outage. I had a problem with it. Therefore, it is an object of the present invention to provide a public telephone capable of changing the number of coins stored, which has a simple circuit configuration and which does not stop service even in the event of a power outage. For this reason, in the present application, the photodetection element provided at the position of the fourth accumulated coin is shared for counting accumulated coins and controlling the reminder sound during power on and during power outage.
In the event of a power outage, the reminder sound is selectively controlled by the second contact CC ₂ and the changeover switch. Hereinafter, embodiments of the present invention will be described in detail based on the drawings. FIG. 2 is a circuit diagram showing an embodiment of a reminder sound control device for a public telephone set according to the present invention, and only the parts necessary for explanation are shown. In Fig. 2, the same numbers as in Fig. 1 indicate corresponding parts, and D ₂ , D ₃ ...D ₇ are diodes, and the diodes D ₂ , D ₃ , D ₆ , D ₇ form a bridge circuit. There is. nv ₁ , nv ₂ ... nv ₈ are contacts of a relay NV (non-latching relay) not shown that operates while energized, R ₃ , R ₄ ... R ₇ are resistors, and Tr is a switching transistor for the reminder sound oscillation circuit TG. , LD is a light emitting diode, PT is a phototransistor which together with the light emitting diode LD constitutes a photodetector, TF is a reminder sound output transformer, C is a capacitor for coupling the reminder sound output, and T.OUT is a reminder sound output. ZD is a constant voltage diode that supplies power to the reminder sound oscillator circuit from the central office line during a power outage, and TS ₁ , TS ₂ , and TS ₃ are mechanical switches that change the charge for one call from 10 yen to 20 yen, respectively. It shows the yen hour, and the side shows the 20 yen hour. KP is a polarity reversal signal detection relay, and VR is a varistor CUT connected in parallel to the input side of the reminder sound oscillation circuit TG, which is a control circuit that counts the output of the transistor PT and sends out a reminder sound control output. It is mainly composed of LSI. One side of the polarity reversal detection relay KP is connected to the pole line terminal _L2 via a diode _D6 , and the other is a diode whose anode side is connected to the station line terminal _L1 via diodes _D4 and _D5 in series. It is connected to the cathode side of D ₃ and to the common contact of contact nv ₁ of relay NV, the normally closed contact of this contact nv ₁ is connected to the station line terminal L ₂ via diode D ₆ ,
Its normally open contact is connected to the junction of diode D ₃ and diode D ₅ . The anode side of the light emitting diode LD is a non-latching relay NV.
is connected to the common contact of contact nv ₁ through the normally closed contact of contact nv ₂ and resistor R ₃ in series, and the cathode side is connected to the transmitter through the normally closed contact of contact nv ₃ of non-latching relay NV. Connected to T. Further, the normally open contact of this contact nv ₂ is connected to the positive pole side (+) of the power supply via a resistor R ₄ , and the normally open contact of the contact nv ₃ is grounded. On the other hand, the normally closed contact (on the 10 yen side) of mechanical switch TS ₁ for changing the rate of 10 yen/20 yen per call is connected to the connection point between resistor R ₃ and the normally closed contact of contact NV ₂ . ₁ normally open contact (20 yen side) is the central line terminal
It is connected to L ₂ and also to the normally closed contact (10 yen side) of mechanical switch TS ₃ . and,
The common contact of the mechanical contact TS ₁ is connected to the second contact CC ₂ which monitors the presence or absence of the second coin among the accumulated coins.
connected to the common contact of mechanical contact TS ₂ via
The normally closed contact of this mechanical contact TS ₂ (10 yen side) is connected to the normally closed contact of contact NV ₃ of the non-latching relay NV, and the normally open contact of mechanical contact TS ₂ (20 yen side) is connected to the mechanical contact. It is connected to the normally open contact (20 yen side) of TS ₃ , and the common contact of this mechanical contact TS ₃ is the first one that monitors the presence or absence of the first coin among the coins stored in advance in the coin storage mechanism. Contact CC ₁ and diode
The cathode side is connected via _D7 in series to the anode side of a diode _D2 whose cathode side is connected to the central line terminal _L1 . One input end of the reminder sound oscillation circuit TG is connected to the connection point of the transmitter T and the constant voltage diode ZD via the normally closed contact of the contact nv ₄ of the non-latching relay NV, and the normally closed contact of the contact nv ₄ of the non-latching relay NV is The open contact is connected to the positive side (+) of the power supply via a resistor _R5 , and the other input end of the reminder tone oscillation circuit TG is connected to the collector of the switching transistor Tr. Also,
The emitter of this transistor Tr is connected to the common contact of contact nv ₈ of non-latching relay NV, and the base is connected to the emitter via resistor R ₆ , as well as the common contact of contact nv ₆ of non-latching relay NV.
is connected to the common contact piece. The collector side of the phototransistor PT is connected to the transmitter T via the normally closed contact of the contact _nv5 of the non-latching relay NV.
is connected to the connection point between and constant voltage diode ZD,
The emitter side is the contact point of the non-latching relay NV.
Non-latching relay via NV ₇ normally closed contacts
NV contacts are connected to the normally closed contacts of NV ₆ . In addition, the normally open contact of contact nv ₅ of non-latching relay NV is connected to the positive side (+) of the power supply, and the contact
The normally open contact of nv ₆ is connected to the output end of the control circuit CUT, the normally open contact of contact nv ₇ is connected to the input end of the control circuit CUT and is grounded via resistor R ₇ ,
In addition, the normally closed contact of contact NV ₈ is a constant voltage diode ZD
The normally open contact is grounded. The output of the reminder sound oscillation circuit TG is configured to be sent to the reminder sound output T.OUT via the reminder sound output transformer TF. Next, the operation of the embodiment shown in FIG. 2 will be explained with reference to FIG. 3. In Fig. 3 a, b, and c, the same reference numerals as in Fig. 2 indicate corresponding parts.
CN indicates accumulated coins and TK indicates coin trajectory. and,
The shaded area in FIG. 3a shows the installation point of a light detection section consisting of a light emitting diode LD and a phototransistor PT provided at the position of the fourth accumulated coin. First, during power supply, if the charge per call is 10 yen or 20 yen, the switching is performed by mechanical switches TS ₁ to TS ₃ for switching between 10 yen and 20 yen, respectively.
Here, 10 yen hour means that the charge for one call is in units of 10 yen, and 20 yen hour means that the charge for one call is 20 yen.
This shows the case in yen units. Then, the non-latching relay NV is in an operating state while energized, and its contacts nv ₁ to _{nv 8} are respectively switched to the normally open side as shown by dotted lines in the figure. When contacts NV ₁ to _{NV 8} switch to the normally open side shown by the dotted line, the light emitting diode
Current flows through the LD through the (+) - resistance R ₄ - contact nv ₂ - light emitting diode LD - contact nv ₃ - ground path, so it emits light, and the phototransistor PT receives the light and transfers it between its collector and emitter. becomes conductive, and the output of phototransistor PT becomes the counting input of control circuit CUT. This counting input is counted by the control circuit CUT, the number of accumulated coins is memorized, and when the accumulated coins reach zero,
A reminder sound control output is sent from the counting circuit CUT.
Based on this reminder sound control output, the transistor Tr is switched to control the reminder sound oscillation circuit TG, and the reminder sound oscillation circuit TG is connected to the reminder sound output T/OUT.
You can get a reminder sound from. The reminder tone thus obtained is sent to the telephone receiver, and by listening to this reminder tone, the user can know that the coin is missing. On the other hand, when a polarity reversal pulse (charging signal) that arrives from the office at the same time as the called party's response is supplied to the office line terminal L ₂ (+) and office line terminal L ₁ (-), the polarity reversal detection relay KP operates. The accumulated coins are stored by a coin storage magnet (not shown). In this case, if the charge for one call is 20 yen, one billing signal (office line terminal L ₂
Two 10 yen coins are stored in succession, one for each (+)). Next, the charge for one call during a power outage is 10
During the yen period, if there is a power outage, the non-latching relay NV will be in the recovery state. Then, by inserting two coins, the first contact CC ₁ is opened as shown in Fig. 3a.
and the second contact CC ₂ respectively operate. During the power outage, relay KP is short-circuited, so the first polarity reversal pulse (billing signal) (station line terminal L ₂
(+)) is held in the second position, and the second contact
CC ₂ then connects the station line terminal L ₁ after the end of the polarity reversal pulse.
(+) and the next coin falls to the position of the first contact CC ₁ , and then the operation is restored. At this time, the path of the polarity reversal pulse (charging signal) is

This is done through a loop of [Table]. At this time, a current flows through the light-emitting diode LD, which has been released from the short circuit, so that it emits light, and the phototransistor PT that receives this light emission is turned on as shown in FIG. 3b. When this phototransistor PT turns on,
A base current flows through the switching transistor Tr, turning it on, and accordingly flows through the reminder tone oscillation circuit TG, generating a reminder tone and sending it to the receiver from the reminder tone output T.OUT. Therefore,
As in the case of energization described above, the user can know that the coin is missing by listening to this reminder sound. Next, when it is 20 yen, that is, when the charge for one call is 20 yen, the mechanical switch TS ₁ to switch between 10 yen and 20 yen is activated.
Switch TS ₃ to the 20 yen side (). Then, the non-latching relay NV is restored and each of its contacts nv ₁ ~
nv ₈ are each switched to the normally closed side, so the third
As shown in Figure a, when four coins CN are inserted, the first and second contacts CC ₁ and CC ₂ operate, respectively. Also, as shown in Figure 3a, the fourth coin CN has a light emitting diode LD and a phototransistor.
Even if the light emitting diode LD emits light, the light is blocked by the coin CN and the phototransistor PT cannot receive the light. (Figure 3c
) Then, two coins are stored by the first polarity reversal pulse (charging signal) (station line terminal L ₂ (+)). Here, the coin storage mechanism is configured to store two coins at a time, unlike when energized, and the stopper does not move the third and fourth coins.
After that, it becomes the station line terminal L ₁ (+) after the polarity inversion pulse ends, and then moves to the first and second positions. The current path at this station line terminal L ₂ (+) is

This is done through a loop of [Table]. Here, current flows through the light emitting diode LD, but as shown in FIG. 3c, the phototransistor PT is not turned on because of the coin CN, and therefore no current flows through the reminder tone oscillation circuit TG. Then, the light emitting diode LD is turned on by the second polarity reversal pulse (billing signal). In this case, since there is no interruption by a coin, the phototransistor PT turns on, and accordingly the reminder tone oscillation circuit TG generates a reminder tone in the same way as when the charge per call is 10 yen. . As is clear from the above description, according to the present invention, a photodetector provided for counting accumulated coins during energization is combined with a mechanical contact operated by coins.
In the case of power on or power outage, the charge per call is 10 yen/
The practical effect is extremely large because it can easily respond to changes of 20 yen. It is also extremely effective in that it can be easily switched using a combination of mechanical contacts operated by coins, light emitting diodes, and phototransistors.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a reminder sound control device for a conventional public telephone, FIG. 2 is a circuit diagram of the main parts of an embodiment of the reminder sound control device for a public telephone according to the present invention, and FIG. FIG. 3 is an explanatory diagram for explaining the operation of the embodiment shown in FIG. 2; TS ₁ ~ TS ₃ ...10 yen/20 yen switching mechanical contact, LD
...Light emitting diode, PT...Phototransistor,
CC ₁ ...First contact, CC ₂ ...Second contact, TG
...Reminder sound oscillation circuit, CN...coin.

Claims (1)

[Claim for Utility Model Registration] Using a commercial power source, when the last stored coin is stored, a reminder sound oscillation circuit is generated based on the operation of a coin contact (CC ₂ ) provided at the second position of the stored coin. In a reminder sound control device for a public phone that is driven to send a reminder sound to users, an optical detection element is installed at the fourth coin position, and the number of coins to be stored per unit call time is one coin. and a control circuit that counts accumulated coins by the output of an optical detection element that is driven when the commercial power supply is turned on and controls a reminder sound oscillation circuit based on the count result. , a first supply circuit that supplies a polarity reversal charging signal to the optical detection element according to the state of the changeover switch and the coin contact (CC ₂ ) during a power outage; A reminder sound control device for a public telephone, comprising a second supply circuit that supplies power from a local current.