JPH0628868Y2 - Doorphone calling device in a home exchange - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to an intercom calling device for a home exchange, and more particularly to a calling device useful when the intercom is used as an in-home child phone.

[Prior Art] A wide variety of in-home telephone exchanges are available that can arbitrarily switch the connection from a parent device connected to a telephone line to a plurality of child phones, doorphones, monitors, wireless cordless handsets, etc. installed in the home. It is commonly used and forms the main part of data transmission in various business establishments and general households.

In such a private branch exchange, call switching is normally performed between the main unit and a plurality of child phones connected to it, but as is well known, it is necessary to connect an intercom to such a private branch exchange. The base unit recognizes the foreign body by operating the call button of the foreign unit, and the off-hook of the base unit establishes a call between the base unit and the intercom.

Since such an intercom is extremely inexpensive and convenient, its original usage form has been expanded, and there has been an increasing demand for the same use as that of a general in-home child phone.

That is, instead of arranging a child phone in each room of the home with respect to the base unit, an intercom is installed in each room instead of this to realize a simple communication method between the base unit and the doorphone.

[Problems to be Solved by the Invention] However, when the conventional intercom is used as it is as a home sub-phone, there are some inconveniences with respect to two-way communication.

In other words, in the relationship between the intercom and the base unit, when a call is made from the base unit to the doorphone, regardless of the state of the intercom, a state in which the call can be immediately made by a doorphone selection operation on the base unit or a doorphone connection operation such as off-hook on the base unit. Since the intercom side cannot obtain the sound like the ring tone of a conventional small telephone, the state that a call is established between the two cannot be confirmed, and the privacy of the room where the intercom is installed is protected. There was a problem that it was not possible, that is, the ambient sound from the base unit side could be easily opened without any advance notice.

The present invention has been made in view of the above conventional problems, and an object thereof is to generate a ringing tone in the intercom when the master unit performs the intercom connection operation when the intercom is used as a home sub-phone. And to provide a doorphone calling device that allows a person in a room where the doorphone is installed to perceive the line connection before making a voice call from the base unit.

[Means for Solving the Problems] In order to achieve the above object, the present invention has a ring tone generator for sending a ring tone to the intercom when the intercom connection operation is performed inside the master unit. Thus, when the intercom is called from the base unit, a ringing sound is generated a predetermined number of times in the intercom based on the connection operation.

[Operation] Therefore, according to the present invention, when the master unit calls the intercom, a preset ringing tone signal is sent to the intercom and a predetermined ringing tone is generated at the intercom. This allows people near the door phone to know the line connection,
It is possible to protect the privacy of the room where the doorphone is installed.

[Embodiment] A preferred embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a main part of a home telephone exchange suitable for the present invention, and although not shown in detail in the main unit 10 of the home exchange, a plurality of child telephones are connected from a terminal 12. ing.

A plurality of intercoms are further connected to the base unit 10. In the embodiment, these intercoms are denoted by reference numerals 14, 16, and
It is shown at 18.

A switching unit 20 and a CPU 22 are provided inside the base unit 10 and exchange control is performed.

The switching device 20 performs the switching of the sub-phone and the intercom and the hook detection as described above, and the terminal 10a for the telephone line.
, And the connection is switched between the telephone line, the handset, and the handset. The switching device 20 and the intercoms 14, 16 and 18 are connected by a voice line 24 and a call line 26, and the intercom 14 passes through the call line 26 by a call button operation to switch the switching device 20. A call detection signal is input to the controlling CPU 22 and the CPU 2
Reference numeral 2 causes the base unit 10 to generate a ringing tone. Then, after switching the target intercom 14 based on this, when the master device 10 goes off-hook, the voice line 24 is established.

On the other hand, when calling from the base unit 10 to the intercom 14, the voice line 24 is simultaneously connected to the off-hook of the base unit when the intercom 14 is selected, and to the selection operation after the off-hook when the intercom is not selected. Once established, the call is ready to go.

In the embodiment, a transmitter 28 and a receiver 30 on the base unit 10 side are connected to the switching unit 20.

In such a private branch exchange, as described above, the connection between the base unit 10 and the intercom has priority over the base unit, so that a ring tone is emitted by the base unit 10 when a call is made from the intercom. The off-hook on the side of the base unit 10 enables the two-way call, but conversely, the intercom 14 does not respond to the call from the base unit 10, and the two-way call is completed.

A feature of the present invention is that the ring tone generation operation of the intercom is performed in the base unit 10 in order to eliminate the problem that the call state is started at the same time as the connection operation in the base unit. In order to
Is provided with a ring back tone generator 32.

Further, the CPU 22 controls not only the ringing tone generation control but also various functions such as generation switching between the DTMF signal and the pulse signal.

In the embodiment, the ringing tone generator 32 includes the CPU 2
A clock pulse output from the clock pulse output terminal 34 of No. 2 is supplied, and includes a frequency divider 36, a ringing tone output circuit 38, and a comparator 40 inside, and when the intercom connection operation is performed, a predetermined number of times of ringing Through the switch 20,
It can be output to the call line 26.

In the preferred embodiment, this ringtone is set to sound a 400 Hz occurrence once.

Therefore, when the base unit 10 calls the intercom, a ringing tone is generated once at the doorphone 14 at the same time as the connection operation, and this ringing tone can notify the intercom side of the line connection start.

In order to perform such an action, the ringing tone generator 32
The high frequency clock pulse supplied from the CPU 22 is supplied to the frequency divider 36, and the frequency divider 36 outputs the ringing tone output circuit 38.
To the comparator 40, while outputting a signal of 400 Hz to the comparator 40.

The comparator 40 has a desired number N of ringing tones specified from the outside.
As a result, the number of ringing tones can be arbitrarily set.

Then, the ringing tone output circuit 38 receives the connection operation confirmation signal from the CPU 22 and the output of the comparator 40, calculates the logical product of the both, and sends out the ringing tone of 400 Hz to the intercom 14 via the switch 20.

Therefore, according to the present embodiment, when any of the intercoms 14 to 18 is operated to be connected from the base unit 10, the selected intercom side hears one ringing tone at the same time as the connection operation, and the line connection of the intercom is confirmed. Can be perceived.

In the embodiment described above, the ringing tone is always generated by the call signal from the base unit 10. However, in the present invention, the changeover switch 14a for arbitrarily invalidating such ringing tone output. Is provided in the intercom 14, which allows the ringing tone to be stopped when the intercom is placed in a sick person or a child room.

Further, in this embodiment, the voice line 24 and the call line 26 are separate systems, but both lines can be shared. In this case, for example, the call signal generated by the operation of the call button provided on the doorphone can be transmitted. , Voice line 24
It is possible by sending to the transmission line from the intercom side of. Then, the switching device 20 detects the call signal and generates a predetermined sound, and thereafter, the off-hook of the master unit enables the two parties to talk.

Similarly, the ringing tone signal from the base unit 10 can also be sent to the voice line. In this case, the changeover switch 14a
Can stop ringing and stop intercom output.

[Effects of the Invention] As described above, according to the present invention, an inexpensive intercom can be used more simply and easily as if it were a sub-phone, and a ringing tone can be obtained in response to a connection operation from the master unit. Therefore, it is possible for people in the room to perceive the line connection, and it is possible to install the intercom without worrying about the privacy problem.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of a private branch exchange provided with an intercom call confirmation device according to the present invention. 10 ... Master device 14, 16, 18 ... Doorphone 20 ... Switching device 22 ... CPU 24 ... Voice line 26 ... Call line 32 ... Ring tone generator

Claims (1)

[Scope of utility model registration request] 1. A private branch exchange comprising: a base unit connected to a telephone line; and at least one intercom connected to the base unit and capable of making a call by a connection operation at the base unit. A ringing tone generator that supplies a ringing tone a predetermined number of times to the intercom by the connecting operation is built in, and when the connecting operation from the base unit side to the intercom side is performed, a ringing tone that notifies the parent unit calling is generated on the doorphone. The intercom calling device in the home switch.