JP2535846Y2 - External line interface of telephone switching system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application field] The present invention relates to an external line interface of a telephone exchange system such as a private branch exchange, a key telephone device, etc., and in particular, a difference in an external line dial system (multi-frequency dial system or DC intermittent dial system). ) Relates to an external line interface which can be economically dealt with.

2. Description of the Related Art As is well known, a multi-frequency dialing method (hereinafter, referred to as a dialing method) in which a dial signal is composed of a combination of two AC signals is known as a dialing method for external lines (office lines, dedicated lines, etc.) accommodated in a telephone exchange system. , MF system), and a DC intermittent dial system (hereinafter, referred to as DP system) that forms a dial signal based on the number of intermittent DC loops of a communication line. An external line interface for accommodating external lines in a telephone exchange system. Must be configured to handle the above two types of dialing schemes.

Conventionally, as a method of coping with the two types of dial systems, a method of separately setting an external line interface for the MF system and an external line interface for the DP system, and transmission of dial signals of both the MF system and the DP system to the external line interface. Add a function and match the dialing method of the outside line to be connected,
A method of selecting one of the methods is adopted.

[Problem to be Solved by the Invention] The former conventional technique requires two types of devices as an external line interface. Especially in recent years, telephone line MF
It is not preferable to manufacture an independent device for the outside line of the DP system, which is becoming a minority and is becoming a minority, because it increases the inventory of products.

Further, in the latter conventional example, the function of transmitting the DP system dial signal is provided even to the external line interface connected to the MF system external line, and the function is useless because it is not used. In addition, the DP dial signal transmission circuit generally requires a high withstand voltage and the number of intermittent communication lines is extremely large, so it is necessary to use a relay having a long-life contact, resulting in an extremely high external line interface. .

The present invention proposes to solve the above problems.
It is an object of the present invention to obtain a configuration of an external line interface that can economically cope with a difference in an outside line dial system.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides an additional device having a switch unit that is switched on and off by dial information, separately from the external line interface, and connects to an external line whose dial system is a DP system. In addition, the additional device is added to the external line interface to provide a function of transmitting a dial signal of the DP system.

[Operation] In the present invention, by preparing an additional device having a simple configuration, it is possible to eliminate the need for two types of external line interfaces due to differences in the dial system, or to require both dial type signal transmission function units in the external line interface. do not do.

Embodiment FIG. 1 is a circuit diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of a telephone exchange system using an external line interface according to an embodiment of the present invention.

The embodiment shown in FIG. 1 is an example in which the present invention is applied to an external line interface of a digital telephone exchange system.

The external line interface 1 includes an incoming call detector 101 for detecting an incoming call from the external line L, a switch 102 for forming a DC loop with respect to the external line L, and a 2-line to 4-line line for separating voice into transmission voice and reception voice. A network 103 including a conversion circuit, the network 1
03, a diode bridge 104 inserted into the communication path to make the polarity of the current supplied from the external line L supplied to 03 constant, transformers 105, 106 respectively relaying the transmission voice and the reception voice separated by the circuit 103, It includes a PCM codec 107 for performing mutual conversion between voice and received voice and PCM code, and the configuration itself is the same as the conventional MF type external line interface, but the feature of the present invention is that a circuit network 103 and a diode bridge 104 are provided. on one line l ₁ of the call line between, the piece lines l ₁
Are provided with a pair of jumper terminals T ₁ and T ₂ .

Further, the additional device 2 provided separately from the external line interface 1 includes a relay 201 for connecting and disconnecting the communication line, a break contact 202 thereof, a transistor 203 for driving the relay 201, and the like.

When the external line interface 1 is used as an MF type external line interface, the jumper terminals T ₁ and T ₂ are connected by a jumper line j and the additional device 2 is not used (that is, the connection between the external line interface 1 and the additional device 2). l ₂ ,
l ₃ is not provided. ).

Further, when using the external line interface 1 as external line interface for DP system, removing the jumper line j (i.e., without connection between the jumper terminals T _1, T _2), jumper terminals T _1, T ₂ and electric Terminals T ₃ and T ₄ connected to locations that are substantially equivalent to each other and terminals T ₁₁ and T ₁₂ connected to the contact 202 of the additional device 2 are connected by connections l ₂ and l ₃ . Note that the connections l ₂ and l ₃ may be provided directly between the terminals T ₁₁ and T ₁₂ and the jumper terminals T ₁ and T _2, and connector terminals are used instead of the jumper terminals T ₁ and T _2. Instead of the jumper j, a U-link that comes into contact with and separates from the connector terminal may be used.

FIG. 2 shows the configuration of the telephone exchange system using the external line interface 1 and the additional device 2 described above.

In FIG. 2, ME is a telephone exchange system, L ₁ and L ₂ are external lines of MF and DP dial systems, and TE is a telephone. In the telephone exchange system ME, 11 and 12 are external lines. An interface 2 is an additional device described with reference to FIG. 1, and 3 is a PCM time-division switch (hereinafter, referred to as a switch) for setting a communication path between the outside lines L ₁ and L ₂ and the telephone set TE. ), 4 is an extension interface for accommodating the telephone set TE in the telephone exchange system, and 5 is a control unit for generally controlling the telephone exchange system.

In the system configuration shown in FIG.
Reference numeral 11 denotes an MF interface that is connected to the jumper terminals T ₁ and T ₂ described above with reference to FIG. 1 by a jumper wire j and conforms to the MF external line L _1.
Reference numeral 12 denotes an external line L _{2 of the} DP system which is not connected between the jumper terminals T ₁ and T ₂ but is provided with the additional device 2 and connected between the terminals T ₃ and T _{11 and} between the terminals T ₄ and T _12. The DP interface conforms to. The control terminal T ₁₃ of the additional unit 2 is connected to the control unit 5 of the telephone switching system ME via the control line l _4.

When performing external call operation in the telephone TE, the control unit 5 extension interface 4 via a control line l ₆ detects the external call of the telephone TE, external line interface 11 is vacant or
12. Select and capture 12 (when the line selection is a cable type) or capture the external line interface 11 or 12 selected by the telephone TE (when the line selection is performed on the telephone side like a key telephone device).

When external line interface 11 or 12 is captured, the controller 5 operates the the switch 102 of the external line interface 11 or 12 via the control line l _4, to form a DC loop to the outside line L ₁ or L _2. Thus will the external line L ₁ or L ₂ is captured, dial the destination number is available from the telephone TE.

To explain the transmission operation of the dial signal for the case where the MF scheme outside line L ₁ is captured by the above operation, the control unit 5
Is aware of the type of outside line L _1, captured (that MF scheme is external), reads the dialing code sent from the telephone TE to the control line l ₆ via the extension interface 4, in this case, the external line L ₁ is an MF type outside line, so a conversion table (not shown) (not shown) provided in the control unit 5 is provided.
ROM for code comparison). At this time, a connection path a between the external line interface 11 and the control unit 5 is formed in the switch 3, and the dial code converted into the PCM code in the conversion table is connected to the connection path a and the communication line l _51. The PCM codec 107 converts the PCM dial code into an analog dial signal, that is, an MF-type dial signal, and converts the PCM dial code into a transformer signal, a network 103, a jumper wire j, and a diode. bridge 104, the dial signal of the MF scheme is sent to the external line L ₁ through the switch 102. When the destination answers, the control unit 5 switches the connection path in the switch 3 from a to b by a known control, telephone TE is possible call is connected to the external line L _1.

Further, when the captured external line will be described transmitting operation dial signal when was DP system external L _2, the control unit 5 in this case is aware of the type of the outside line L _2, in this case, since external L ₂ is a DP system outside line, the control unit 5 sends a control line l ₄ the dial code is converted into intermittent information from the read telephone TE in the same manner as above. Since intermittent information sent to the control line l ₄ is input to the terminal T ₁₃ of the additional unit 2, the operation number of times the relay 201 corresponds to the dialing code by the intermittent information repeatedly recovery, call line l ₁ Is repeatedly opened and closed by the contact 202 the same number of times. Thus dialing signals DP method is sent to the to the outside line L _2. When the called party answers, the control unit 5 completes the connection C in the switch 3 by known control, and
There it is possible to call is connected to the external line L _2.

As is clear from the above description, the dial signal
TE from not being directly sent to the external line L ₁ or L _2, is adapted to be delivered are converted in the call switching system ME, telephone switching system to which the present invention is carried out is the so-called dial sender system System.

The embodiment described above is an example in which the invention is applied to an external line interface of a digital telephone exchange system. However, the present invention is applicable to a system having a dial sender function even if the telephone exchange system is an analog system. Can be.

[Effects of the Invention] As described above, the present invention provides a pair of terminals for separating the communication line on one side of the communication line of the external line interface which is originally the MF system, and separately from the external line interface. Providing an additional device having a switch means for intermittently the number of times indicated by the dial information, when using the external line interface as an interface of the DP system external line, release between the pair of terminals of the external line interface, In addition to the additional device, the switch means of the additional device is inserted between the pair of terminals, and in recent years, there is no need for an external line interface only for the DP type external line, which is becoming a minority in recent years, There is an effect that it is possible to economically cope with the difference in the dialing method of the outside line.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of a telephone exchange system using an external line interface according to an embodiment of the present invention. (Main symbols) 1 (11,12)… External line interface T ₁ , T ₂ … Jumper terminal j… Jumper line 2… Additional device 201… Relay, 202… Relay contact ME… Telephone exchange system L (L ₁ , L ₂ ) ... external line TE ... telephone

Claims (1)

(57) [Scope of request for utility model registration] In an external line interface of a telephone exchange system having a dial sender function, an additional device having a switch means for interrupting the number of times specified by dial information is provided separately from the external line interface. A pair of terminals for separating the communication line is provided on one side of the communication line, and when the dialing method of the outside line is a multi-frequency dialing method, the terminals are connected,
A telephone in which the additional device is mounted and the switch means of the additional device is connected between the pair of terminals or at a place electrically equivalent to the pair of terminals when the external line dialing method is a direct current interrupted dialing system. External line interface of the switching system.