JPH0728751Y2 - Telephone device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (b) Industrial field of application The present invention is capable of connecting a plurality of telephones to a single station line, and connecting the telephones to the outside line connection for connecting the telephones to the station line. The present invention relates to a telephone device having an outside line / extension switching means for switching to one of connection states of an extension side connection to be connected and having a call function between the telephones and a call function between the telephone and a central line.

(B) Conventional Technique A conventional telephone device of this type will be described with reference to FIG.

In the figure, (1) is a telephone line connection terminal, which is connected to the office line through this connection terminal (1). (2) is a rectifier circuit, (3a) and (3b) are external / extension switching relays,
The output terminals of the rectifier circuit (2) are connected to the external contacts (P1) and (P3) of the switching relay, respectively.

In addition, the relay side (3a) (3b) extension side individual contacts (P2) (P
4) is connected to the call matrix circuit (4),
Further, the common contacts (q1) (q2) of the relays (3a) (3b) are connected to detection circuits (5a) (5b) for detecting off hook and pulse dial signals. This detection circuit (5a)
(5b) is configured to include a photo coupler, and when off-hook and pulse dial signals are detected,
The detection signal is derived to the arithmetic control means (6) via the lines (l1) and (l2). The arithmetic control means (6) is realized by a microcomputer or the like.

The detection circuits (5a) and (5b) are connected to the extension telephones (8a) and (8b) through the extension telephone connection terminals (7a) and (7b), respectively.

The call matrix circuit (4) is connected to a dial tone transmitting circuit (9). In addition, the call matrix circuit (4) includes an extension side individual contact (P) of the relay (3a).
The crosspoint (10) connecting 2) to the dial tone transmission circuit (9) and the extension side individual contact (P) of the relay (3b)
Connect the crosspoint (11) that connects 4) to the dial tone transmission circuit (9), and the extension-side individual contact (P2) of the relay (3a) and the extension-side individual contact (P4) of the relay (3b). It has cross points (12) and (13). ON / OFF of these cross points (10) (11) (12) (13) and other cross points provided in the call matrix circuit (4) is controlled by the arithmetic control means. Further, the arithmetic control means (6) is a relay (3a)
It also controls the switching in (3b).

Next, the operation will be briefly described.

When the extension telephones (8a) and (8b) are on-hook,
The relays (3a) and (3b) are connected to the extension-side individual contacts (P2) and (P4) by the arithmetic control means (6), and when the extension telephone (8a) is turned off from this state, the detection circuit ( 5a)
The off-hook state is detected at, and the detection signal is input to the arithmetic control means (6) via the line (l1).

The arithmetic control means (6) sets the crosspoint (10) of the call matrix circuit (4) to the ON state in response to the detection signal, and the dial tone from the dial tone transmission circuit (9) is set to the extension telephone (8a). ).

Then, the dial signal from the extension telephone (8a) is monitored, and "0" indicating the outside line call request is displayed at the head of the dial signal.
When is detected, the relay (3a) is switched to the connection state with the outside line side contact (P1), and the extension telephone (8a) is connected to the office line.

On the other hand, when the extension telephone number is transmitted from the extension telephone (8a), the extension telephone number is detected by the detection circuit (5a) and input to the arithmetic control means (6). Thereby, the arithmetic control means (6)
Makes an extension call to the extension telephone (8b). When the extension telephone (8b) is turned off, it is detected by the detection circuit (5b) and input to the arithmetic control means (6).

By this, the arithmetic control means (6) turns on the cross points (12) and (13) of the call matrix circuit (4) to make an extension call.

(C) Problems to be Solved by the Invention According to the above-described conventional technology, it is possible to reliably achieve a call between telephones and a call between a telephone and a central line.

However, only a single telephone can be connected to the station line during a call with the station line, and the so-called conference telephone function cannot be achieved.

(D) Means for Solving the Problems In view of the above points, the present invention is capable of connecting a plurality of telephones to a single office line, and connecting the telephones to the outside line connection for connecting the telephones to the office line. In a telephone device having an outside line / extension switching means for switching to one of connection states of an extension side connection connected to a telephone and having a telephone call function between the telephones and a telephone call function between the telephone and the office line, a three-party call instruction means And a connection means for simultaneously connecting a plurality of telephones to a single station line based on a command from this means.

Further, preferably, the present invention provides a telephone device characterized in that a current supply circuit for supplying a current to the telephone is provided when a plurality of telephones are simultaneously connected to a single station line by a connecting means.

(E) Function According to the present invention, when a telephone is talking to a central line,
Another telephone is connected to the central office line according to the instruction of the three-party call instruction means, so that the three-party call becomes possible.

(F) Embodiment FIG. 1 is a diagram showing a main part of a telephone device according to the present invention.
In FIG. 1, (20) is a telephone line connection terminal, which is connected to the office line through this terminal (20). (21) is a rectifier circuit, (22) is a holding relay, and individual contacts (22
A resistor (23) is connected between a) and the reference potential point. (2
4) (25) (26) are external line side individual contacts (24a) (25a) (26
a) is an outside / extension switching relay connected to the output terminal of the rectifier circuit (21) via the holding relay (22), and individual extension side individual contacts (24b) (25b) (26b) respectively connect a capacitor and a resistor. The common contact (24c) (25c) is connected to the call matrix circuit via the common contact (24c) (25c), and the common contact (26c) is connected to the detection circuit (27) (28) that detects the pulse dial signal. Each of them is connected to the communication circuit (29) of the main device (which is directly connected to the line).
The detection circuits (27) and (28) are connected to the extension telephones via the relays (30) and (31) and the extension telephone connection terminals (32) and (33), respectively. (34) is the speaker of the handset of the base unit, (35) is the microphone of the handset of the base unit, (36) is the call matrix circuit, (37) is the relay side contact (30a) of the relay (30) (31). ) (31a) connected ringing tone generation circuit,
(38) is a level detection circuit for detecting the level of the ring back tone output from the ring back tone generation circuit (37), and outputs a detection signal (S1) when the level of the ring back tone is below a predetermined value.
(39) is an arithmetic and control unit composed of a micro computer, which constitutes a connecting unit. (40) is composed of a plurality of transistors, and relay coils (22L) (24L) according to control signals (S2) to (S7) from the arithmetic control means (39).
It is a relay driver circuit that selectively excites (25L) (26L) (30L) (31L). Relay coil (22L) (24
L) (25L) (26L) (30L) (31L) are relays (22)
(24) (25) (26) (30) (31) is switched and controlled. In order to clarify the correspondence between the relay coil and the relay, "L" is added to the relay coil code. Is shown. (41) is a first call switch for calling an extension telephone (hereinafter, referred to as a first slave unit) connected to the extension telephone connection terminal (32), and (42) is an extension telephone connection terminal (33). A second call switch for calling a connected extension telephone (hereinafter referred to as a second cordless handset), (43) is a three-party call switch that is operated when making a three-party call, and (44) is a power input terminal , (45) is a stabilized power supply circuit, (46) is a current supply circuit, and includes transistors (47) (48) and resistors (49) (5
It is composed of 0) (51) (52).

Next, the operation will be described with reference to the flow chart of FIG.

Assuming that the main unit is now talking to the local line by an incoming call from the central line or an outgoing call from the main unit, the holding relay (22) is connected to the contact (22b), and the external / extension switching relay (24). (25) to the individual contacts (24b) (25b) on the extension side, the external / extension switching relay (26) to the individual contacts (26a) on the external line, relays (30) (3)
1) is connected to the contacts (30b) (31b), respectively.

In such a state, the first call switch (41) for calling the first handset because the three-party call including the first handset is performed.
When the key is operated (step 5), a key signal of, for example, an H level output from the arithmetic control means (39) via the line (53) is input via the first call switch (41) and the line (55). It is supplied to the arithmetic control means (39) as a return signal.

The arithmetic control means (39) supplies a control signal (S4) to the relay driver circuit (40) in response to the key return signal, and the relay driver circuit (40) accordingly operates one end of the relay coil (22L). Ground and excite the relay coil (22L).

When the relay coil (22L) is excited in this way, the holding relay (22) is connected to the holding side individual contact (22a), and the office line is held by the resistance (23) (step 8).

In addition, control signals (S3) (S7) from the arithmetic control means (39).
Is supplied to the relay driver circuit (40), and in response thereto, the relay coils (26L) (30L) are excited to switch the outside / extension switching relay (26) to the individual contacts (26b) on the extension side and the relay (30 ) Is switched to the calling side individual contact (30a).

After that, the arithmetic control means (39) outputs the control signal (S8) to set the ringing tone generating circuit (37) to the operating state, and the ringing tone from the ringing tone generating circuit (37) is set to the first level. It is sent to the child device (step 9).

Then, when the first slave unit is turned off, a direct current loop is formed, and as a result, the level of the ringing tone is lowered. Such a level drop of the ringing tone is detected by the level detection circuit (38), and the detection signal (S1) is supplied to the arithmetic control means (39).

In response to this, the arithmetic control means (39) outputs a control signal to the call matrix circuit (36) and connects the lines (57) and (58), that is, sets the extension call state.

After checking the off-hook of the first cordless handset by the voice from the first cordless handset or the light-emitting element that lights up when the line is connected to the cordless handset, when the user operates the three-way call switch (43) (step 11 ), The key signal output from the arithmetic control means (39) via the line (53) is supplied to the arithmetic control means (39) as a key return signal via the three-way call switch (43) and the line (54). It

The arithmetic control means (39) supplies control signals (S2) (S3) (S4) (S7) to the relay driver circuit (40) according to the key return signal, and the relay driver circuit (40) responds to this. Relay coil (24L) (30L) (22L) (26L)
Excite.

Therefore, the outside / extension switching relays (24) and (26) are connected to the outside line individual contacts (24a) and (26a), and the holding relay (22) is connected to the non-holding side individual contacts (22b). The relay (30) is also connected to the non-call side individual contact (30b) (step 12).

Thus, it becomes possible to make a three-party call with the other party via the master unit, the first slave unit, and the office line.

At the time of such a three-party call, there is a possibility that the call cannot be made only by the power from the office line due to the DC resistance value of the connected telephone.

Therefore, in the present invention, the above-mentioned problem is solved by supplying the H level control signal (S9) from the arithmetic control means (39) to the current supply circuit (46) during a three-party call.

That is, as a result of the transistor (47) being turned on in response to the H level signal from the arithmetic control means (39), the base current of the transistor (48) flows, the transistor (48) is turned on, and the stabilized power supply circuit is turned on. The current stabilized in (45) is supplied to the parent device and the first child device via the diode (59), the resistor (49) and the transistor (48) (step 13).

In such a three-party call state, when it is detected that the master unit or the slave unit is hooked up, the arithmetic control means (39) inverts the control signal (S9) to the L level and the current supply circuit (46). And the control signal (S2) or (S7) supplied to the relay driver circuit (40) is inverted to L level to disable the relay coil (24L) or (26L), and the external line / extension line The switching relay (24) or (26) is connected to the extension-side individual contact (24b) or (26b) (steps 16 and 17).

Thus, although the three-party call including the child device is released, when releasing the three-party call, not only the above-described method but also a separate release switch may be provided.

After that, it is detected whether or not the master unit or the slave unit making the two-way call is turned on. If it is turned on, the on-hook process is performed and then the standby state is restored (steps 18,1).
9).

When a three-party call is made at the other party via the master unit, the second slave unit, and the office line, the second call switch is operated and the relay (instead of the operation of the first call switch described above). 2
Only the relay (25) is controlled instead of the control of 4), and the basic operation is the same.

Further, when the slave unit desires a three-party call while talking to an outside line, a predetermined DTMF signal is transmitted by operating the ten-key pad of the slave unit, and the arithmetic control means is operated according to the DTMF signal. You can do it.

Furthermore, the parent device in the embodiment is not always necessary, and can be applied to the case of only the child device.

(G) Effect of the Invention According to the present invention, since a plurality of telephones are simultaneously connected to a single office line, a multi-party call is possible.
Further, by providing a current supply circuit for supplying a current to the telephones only when a plurality of telephones are simultaneously connected to the single station line, it is possible to reliably carry out a multi-party call. Especially when using a battery as a power source, for example, when using a backup battery for a power failure,
It is more effective because it can reduce battery consumption as much as possible.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of the present invention, FIG. 2 is a flow chart, and FIG. 3 is a view showing a conventional example. (22) ... holding relay, (24) (25) (26) ... outside / extension switching relay, (27) (28) ... detecting circuit, (36) ... call matrix circuit, (37) ... ring tone generating circuit, (38) ... Level detection circuit, (39) ... Arithmetic control means (connection means),
(40) ... Relay driver circuit, (41) ... first call switch, (42) ... second call switch, (43) ... three-party call switch, (46) ... current supply circuit.

Claims (1)

[Scope of utility model registration request] 1. A plurality of telephones can be connected to a single station line, and the connection state is either one of an outside line connection for connecting the telephones to a station line and an extension side connection for mutually connecting the telephones. In a telephone device having an external / extension switching means for switching and having a telephone call function between the telephones and a telephone call function between the telephone and the office line, a three-party call command means and a single station line based on the command of this means And a current supply circuit for supplying a current to the telephone only when a plurality of telephones are simultaneously connected to the single office line by the connecting means. Telephone equipment to do.