JPS597254B2 - Improved parent-child telephone device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to providing a device that can provide functions such as confidential communication, hold, transfer, and inter-extension communication to a conventional parent-child telephone.

One telephone line is used by multiple telephones by connecting multiple telephones in parallel to one telephone line, or by operating a converter to connect one telephone line to any of the plurality of telephones. There is a parent-child phone that can be used as a phone, but it has the disadvantage of not having functions such as confidential calls, hold calls, and inter-extension calls.

In response, a push-button telephone device has been proposed, but its extremely high price has prevented its widespread use in general homes. In order to eliminate the drawbacks of these conventional devices, the present invention provides an improvement in which a main device and a telephone additional device are installed in a conventional parent-child telephone, and the main device and the telephone additional device are connected by a four-wire wire. Its purpose is to provide a form parent-child phone. Hereinafter, the present invention will be explained in detail with reference to the drawings as examples. The figure is a circuit configuration diagram as one embodiment of the present invention.

In the figure, ME is a main device, and ADP is an additional device for telephones provided corresponding to each telephone. In the main device ME, terminals Ll and L2 are terminals connected to the telephone line TRK, Tl, t2, t3, and t4 are terminals connected to the additional device ADP, and Lp and Ls are the windings of the loop monitoring relay L of the telephone line. LP is its primary winding, Ls is its secondary winding, t is the contact of relay L, H is the winding of the always-operating relay, H
O, hl, h2, h3, h4 are the contacts of the relay H, HL is the winding of the hold relay HL, HtO, htl, h, /. 2 is the contact of the relay HL, R is the calling signal receiving circuit, R is the winding of the calling signal receiving relay, r is the contact of the relay R, 0SC is the extension calling signal generator, AMP is the extension calling signal amplifier,
SWl is a switching circuit, 1, 2, 3 are input/output terminals of the switching circuit SWI, SW2 is a switching circuit, 4
, 5, 6, 7 are human output terminals of switching circuit SW2,
REC,1 and REC,2 are bridge rectifiers, D13, D14 are diodes, Tr,, T
r2, Tr3, Tr4 are switching transistors,
R,,,Rl2lRfh3se4? Rl5lRl6! Rl
7 is a resistor, Cll? Cl2? Cl3? Cl4 is a capacitor, CH is a flow coil, Tll is a transformer, and E is a power source. Regarding the additional device ADP, Tl, t2, t3, and t4 are terminals connected to the terminals T, , l2, t3, and t4 of the main device ME, TL and TL2 are terminals for connecting a telephone, and RKO and RKl are extension calling terminals. Contact point of button RK, LK
are the contacts of the telephone line capture button LK, SCRl, SCR2
, SCR3 is a thyristor, ZD2l, ZD. 2 is a constant voltage diode, D22 and D23 are diodes, R2l, R
229R23lR24dchi5dchi6dchi7dchi8 is the resistor・C2l・C22raC! 3 is: ri7>'de2sa)T2
l indicates a transformer, and SP indicates a speaker. Also, the location indicates a normal automatic telephone. Note that the circuit of this automatic telephone has not been changed in any way since it is connected to the device according to the present invention. The operation of the circuit according to the embodiment of the present invention will be explained in detail below with reference to the drawings.

In the main device ME, the switching circuit SWl is always on, and the terminals 1-3 are electrically connected.

Therefore, Ji-ki? Winding H-switching circuit SW,? Relay H operates constantly in the circuit of power supply E, and its contacts HO and hl
, h2, h3, and h4 are moving in the direction shown by the dotted line.

When a calling signal arrives from the telephone line, terminal L1 contact Ht
O capacitor C, relay R of the calling signal receiving circuit RV operates in synchronization with the arrival cycle of the calling signal through the route of contact Htl - terminal!, and by the operation of contact r, amplifier AMP? diode Dl4 - contact r - power supply Activate amplifier AMP with circuit E.

Therefore, the signal of the signal generator 0SC is amplified and sent to the transformer Tl
It is applied between terminal T3 and terminal T4 through 1. The calling signal between terminal T3 and terminal T4 is sent to additional device A corresponding to each telephone.
Since it is sent between terminal T3 and terminal T4 of DP, in the additional device ADP, it is sent to transformer T2 via the route of terminal T3 - capacitor C22 - transformer T2l - contact RKO - terminal T4.
A ringing signal is induced in the terminal ADP, and the speaker SP of each additional device ADP is sounded to indicate an incoming call from the telephone line. When a certain telephone device disconnects the handset of the telephone TDL in order to answer an incoming call from the telephone line or make a call to the telephone line, the transistor Tr is turned on.

Since this transistor Tr, and the resistor R28 in the additional device ADP have sufficiently large values, they are not turned on by the resistors R, 6 and the diode D15 in the main device ME. When the transistor Tr is turned on, the transistor Tr, one resistor R,, T transistor Tr, T
In the circuit of the power supply E, the transistor Tr is turned on, and a voltage is applied between the terminals T and one terminal.

Pressing the telephone line capture button LK in the additional device ADP closes the contact LK. At that time, the switching transistor Tr in the main device ME is on, and the terminal T,
Since a voltage is applied between one terminal T and one terminal T, one contact LK: [main I source E circuit is completed, and the constant voltage diode ZD2l in the additional device ADP becomes conductive. ,
A potential difference is generated across the resistor R22 and the thyristor SCR
, turns on.

Therefore, even if you release the button LK, one terminal T, one terminal T
, - thyristor SCRI remains on. At this time, since the resistance value of the resistor R23 in the additional device ADP is small, the current increases, and the potential difference between the resistor R15 and the transformer Tll in the main device ME becomes large, and the terminals T, - one terminal T, The voltage between the terminals decreases.

Therefore, even if the button LK of the additional device ADP corresponding to another telephone device is pressed after the terminal voltage between terminal T3 and terminal T has decreased in this way, the constant voltage diode ZD2l will not conduct, so that the additional device ADP Thyristor SCRI
is never turned on. By pressing button LK, thyristor SCR is turned on and terminal T, ? Terminal T,
When a current flows between them, the terminals 4 and 6 of the switching circuit SW become conductive due to the potential difference across the resistor RI5 in the main device ME. Therefore, earth - transistor Tr3 - resistor Rl4? switching circuit SW,
Terminal 6 - switching circuit SW, terminal 4 - transistor Tr, - transistor Tr is turned on in the circuit of power supply E, and the ground voltage - transistor Tr, - diode Dll is turned on.
- Since the circuit of terminal 2 of the switching circuit SW, is created, the terminal 1 of the switching circuit SW, which is always operating.
Terminal 3 is turned off.

Therefore, relay H is restored and its contacts HO, hl, h2
, h3, h4 are restored. Due to the restoration of contacts HO and hl, TRI one terminal L, one contact hl - Bri main device ME Tsuji rectifier REC one winding Ls one contact hl one terminal T, one telephone line one terminal T, one terminal TL, one telephone additional device ADP equipment terminal L, - diode D22 constant voltage. Diode ZD resistor R,, one resistor 2'' 1 - capacitor C, , additional device ADP device R 1 right terminal 1 right terminal HO 1 turn - Nor `` A circuit of wire LP - bridge rectifier RECII 1 contact HtO is completed.

At this time, since the voltage on the telephone line TRK side is high, additional equipment A
Constant voltage diode ZD22 in DP becomes conductive, and resistor R
, 6 turns on the thyristor SCR, and the telephone becomes ready to talk to the telephone line side. 1
In addition, even if another telephone equipment removes its handset after terminal T,, terminal T, is connected to telephone line TRK due to restoration of relay H, the loop is not closed by the telephone equipment that is in communication with the telephone line. Since the voltage between the right terminal and the terminal T has decreased, the constant voltage diode ZD22 in the additional device ADP corresponding to the telephone device after removing the handset does not conduct, and the thyristor SCR of the additional device ADP does not conduct. , is not turned on, so a secret story is constructed.

That is, if one telephone device seizes the telephone line, other telephone devices cannot seize the telephone line even if the handset is removed. On the other hand, when the thyristor SCR is turned on, the telephone loop is closed, which activates the loop monitoring relay L of the main device ME, and the closing of its contact t causes the earth to close. Contact t Diode Dl2? The circuit at terminal 2 of contact H3--switching circuit SW maintains the off state of switching circuit SW.

In addition, the ground contact point t-diode Dl3T resistor-7112'
F. ;; ; Circuit capacitor C of one power supply E
l3 is a switching transistor, transistor Tr
, remains on.

Note that when the contacts HO and hl are restored, even if the transistor Tr, which was turned on due to the telephone loop, is turned on, the transistor Trl is turned on while the contact t is closed due to the discharge of the capacitor Cl3. Since the state is maintained, the switching circuit SW2 and the transistor Tr3 are in the on state, and the relay H continues to be in the restored state. Even if the relay L operates intermittently by sending a dial impulse from the telephone side, the transistor Trl remains on due to the discharge of the capacitor Cl3, and the thyristor SCR in the additional device ADP
, also remains on. Additional equipment A whose telephone equipment, ie, thyristor SCR, is turned on during a call to the telephone line.
When the telephone equipment corresponding to DP attempts to transfer the call to another telephone equipment, when the extension call button RK is pressed,
The contacts RKO and RKI operate.

At this time. At this time, the thyristor SCR in the additional device ADP
Since I is on, the potential difference across resistor R23 is connected to thyristor SCR through resistors R24 and R25.
, the thyristor SCR is turned on by the operation of the contact RKO. When the thyristor SCR is turned on, the terminal T3 and the terminal T are short-circuited, so that the thyristor SCR is turned on. Thyristor SCR remains on as long as button RK is pressed. If the thyristor SCR is turned on, the terminal T4, ? Terminal T
, one contact RKO thyristor SCR, one terminal T, one terminal T
3. Current flows through the circuit of resistor R15, transistor Tr, main device ME, and power source E.

This current is amazing! Since the current value is larger than when the iris resistor SCR is in the on state, the potential difference between both ends of the resistor Rl5 in the main device ME becomes larger.

The switching circuit SW is configured so that when the potential difference between both ends of the resistor Rl5 is large, the terminals 4-7 are conductive and the terminals 4-6 are non-conductive. Line HL? Switching circuit SW, (7-4)-? Relay HL operates in the circuit of transistor Trl and power supply E,
The contacts HtO and htlht2 operate.

Due to the operation of contacts HzO and htl, the direct current circuit of the telephone line is suspended by resistor R1. This also cuts off the relay L operating circuit, so it can be restored. As a result, the contact point t is opened, and since the terminals 4-6 of the switching circuit SW, are non-conductive, the transistors Tr,
Since the switch is off, terminal 2 of the switching circuit SWI is opened, so that the relay H operates again. The telephone station is therefore connected to the power supply circuit through the blockage wire CH by the contacts HO, hl. Further, by reactivating the contact H4, the relay HL is self-maintained by the circuit consisting of one ground winding HL, one contact H4, one contact Ht2, the transistor Trl, and the power supply E. On the other hand, since the telephone TEL is connected to the power supply circuit again, the transistor Tr2 is turned on as explained earlier, so even if the contact t is restored, the switching transistor Tr2 is turned on.
1 is maintained in the on state, and voltage continues to be applied between terminal t3 and terminal t4. Therefore, the limited relay HL whose transistor Tr2 is turned on by the telephone loop is maintained.
When you release the button RK of the additional device ADP, the thyristor SCR
2 is turned off, and even if button RK is pressed from now on, thyristor SC will be turned off.
Since R1 is off, it will not turn on again. When the thyristor SCR2 is turned off, the terminals t3 and t4 of the additional device ADP become open, so the potential difference across the resistor R15 of the main device ME disappears, and the switching circuit SW
2 is off, that is, both terminals 6 and 7 are open,
The transistor Tr3 is never turned on. Therefore,
Return to the original state. On the other hand, when button RK is pressed to call another telephone TEL after thyristor SCR2 is turned off, the current between terminals t1 and t2 flowing through the telephone loop and resistor R28 is
Since the resistor R28 is short-circuited by closing the contact RK1 of K, it becomes large while the button RK is pressed. Therefore, since the potential difference across the resistor R16 in the main device ME becomes large, each time the button RK is pressed, the transistor Tr4 is turned on, and the amplifier AMP is activated, and the voltage between the terminals t3 and t4 is output through the transformer T1. A ringing signal is generated in between. This terminal t3
The alternating current that is the calling signal between one terminal t4 is connected to the other telephone TE.
The speaker SP is made to sound through the cocidenser C22 and the transformer T2 in the additional device ADP corresponding to L. This allows another telephone TEL to be called. When the other telephone TEL disconnects the handset, the terminals t and t2 of each additional device ADP are connected in parallel, so the transferor presses the button RK and hears the ringing of the speaker SP, and then disconnects the handset. You can now talk to the transferred party from whom you have removed the button. Main device ME blockage line CH and capacitor C
12. This is to enable this mutual communication. A two-way conversation between the transferer and the transferee allows the transferer to tell the transferee that the call to the telephone line is being transferred. Telephone line capture button LK in additional device ADP
When is pressed, as already explained, the thyristor SCR of the additional device ADP is turned on, and the switching circuit SW1 is turned off due to conduction of the switching circuit SW2 and transistor Tr3 in the main device ME, and the relay H is restored. When the relay H is restored, the self-holding circuit of the relay HL is cut off by its contact h4. Therefore, relay H
Since L is restored and its contacts h' and ht1 are restored, the hold on the telephone line by resistors R and 7 is released, and
The telephone line is connected to the telephone side, the relay L is activated, and as mentioned above, the telephone TEL becomes capable of communicating with the telephone line, and is capable of responding again to the Kaede telephone line. in this case,
The other telephone TEL is connected to the thyristor S in the additional device ADP.
A secret message is created by a secret message circuit constituted by CR3 and a constant voltage diode ZD22. Even if the telephone TEL is in a state where the power supply E is cut off due to a power outage or the like while the telephone TEL is talking to the telephone line, the telephone call can be continued without any problem because the relay H has already been restored. Confidentiality is also maintained. When the power supply E is restored in this state, the loop monitoring relay L operates and its contact t is closed, so the switching circuit S is connected through the diode D12 and the contact h3.
Since terminal 2 of W1 is connected to earth, relay H maintains the restored state. Therefore, if the telephone TEL is talking to the telephone line,
Even if the power supply E is cut off or restored, the call can be continued without any problem. If you do not want to transfer the call to the telephone line, but simply want to make a call between telephones (TEL), the thyristor SCR in the additional device ADP is not operating, so even if you press the extension call button RK, the thyristor will not work. SCR2 does not turn on.

Therefore, when the button RK is pressed, the amplifier AMP is activated through the contact RK1 as described above, and a calling signal can be sent to the other telephone side. If the other party answers, the call can be made. In the embodiment described above, other telephones T
In order to call EL, the signal from the signal generator 0SC is amplified by D by the amplifier AMP and sent out.
By adding the audio output from the telephone TEL that appears between the contacts h0 and h1 and the blockage line CH instead of the signal from the signal generator 0SC to the input, it is possible to call the b1 party by voice. can.

As explained above in detail in the examples, according to the present invention,
It is possible to configure an improved parent-child telephone device with added functions such as confidential talk, hold, and forwarding without modifying the conventional parent-child telephone at all.Moreover, it is possible to construct an improved parent-child telephone device with additional functions such as confidential talk, hold, and forwarding, and to create a connection between the additional device added to the telephone and the main device. It is possible to configure the number of wires connecting the lines to four.

Further, the additional equipment added to the telephone set can be made extremely small, and the cost of the equipment can be reduced.

[Brief explanation of the drawing]

The figure is a circuit configuration diagram illustrating one embodiment of the present invention. ME...Main device, ADP...Additional device.

Claims (1)

[Claims] 1. One telephone line is connected in parallel to an additional device attached to each telephone via a two-line communication line and a two-line control line via the main device, and a plurality of A device used with a telephone has a relay H in the main device that switches the communication line between the telephone line side and the extension side, detects on the extension side communication path that the telephone handset is removed, and responds to the telephone. Pressing the telephone line capture button LK in the additional device is detected by a two-wire control line, and when both detections match, the relay H is activated.
By activating the relay H and switching the communication line to the telephone line side using the contacts of relay H, it is possible to remove the handset and press the button L.
An improved parent-child telephone device characterized in that a telephone line is captured based on a coincidence with pressing K. 2. In a device that is used with multiple telephones, one telephone line is connected in parallel via the main device to an additional device attached to each telephone using a two-wire communication line and a two-wire control line. , having a relay H for switching the telephone line between the telephone line side and the extension line side and a telephone line loop monitoring relay L in the main device, and inserting a switching element into one of the control lines,
A switching element having a self-holding function is inserted between the two control lines in the additional device on the telephone side, and the disconnection of the handset of the telephone is detected on the extension side communication path, and one of the control lines is switched on. Turn on the inserted switching element,
By applying a voltage between the control lines and pressing the button LK in the corresponding additional device on the telephone side, the switching element having the self-holding function is turned on, and the current in the control line generated at this time is transferred to the main device. When the detection of both the removal of the handset and the pressing of the button LK is detected, the relay H is activated, the telephone line is switched from the extension side to the telephone line side, and the telephone line is captured, and the telephone line is captured. The line loop monitoring relay L is operated, and the switching element inserted into one of the control lines is held in the ON state by the contacts of the relay L, and the telephone transmits and receives data by ending the call without using the hook switch contacts of the telephone. An improved parent-child telephone device characterized in that, when the device is restored, a switching element inserted in one of the control lines is turned off by the restoration of a relay L, and the device is restored to its original standby state.