Note: Descriptions are shown in the official language in which they were submitted.
t 33297~
ELECTRONIC PRIVATE BRANCH EXCHANGE
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to electronic private
branch exchanges which have a function to cause a plurality
of specific extension telephone sets to respond to an
incoming signal from a corresponding main wire trunk and,
more particularly, to electronic private branch exchanges
which are capable of changing extension telephone sets which
are caused to produce an incoming signal tone as needed
according to time zones.
2. Description of the Related Art
Conventionally there have been used two types of
reception of an incoming signal to a private branch exchange
from a main wire trunk, one being first by an attendant
console and the other being directly by an extension
telephone. The latter is a so-called "direct inward dialling
system". In the direct inward dialling system, generally
there are provided a plurality of extension telephone sets
for reception of an incoming signal from the corresponding
one of the main wires. For example, a plurality of extension
telephone sets can simultaneously receive and each respond to
an incoming signal from the corresponding main wire trunk.
Generally, high function telephone sets (EKTs) each have a
particular one of a plurality of button keys allocated to the
corresponding main wire. When there is an incoming signal
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from that main wire, a light emitting diode (LED) for the
particular key of each EKT flashes, and the incoming tone is
produced simultaneously at that particular EKT. In order to
respond to the incoming signal, the flashing key of the EKT
may be only pressed.
Another such direct inward dialling system using
EKTs is to only flash a LED for the particular key of each
EKT without producing an incoming signal tone.
A further direct inward dialling system is the
simultaneous use of a subsystem in which an incoming signal
is reported both by production of an incoming signal tone and
by flashing of a LED for an EKT and a second subsystem in
which an incoming signal is reported only by flashing a LED
for another EXT.
The effect of this system is that particular ones
of the EKTs which respond to an incoming signal are virtually
determined. In other words, an incoming signal tone is be
required to be produced only at particular EKTs for persons
responsible at all times for responding to the incoming
signals at all times. Usually, production of an incoming
signal tone at particular telephone sets is effective for
only persons who must respond to that incoming signal and
other incoming signal tones are only noisy to those persons.
Whether particular EKTs are set to produce an
incoming signal tone when there is an incoming signal is
determined on their installation, so that change is not easy.
Thus such EKTs are an inconvenient ones when they are desired
to be switched between production and non-production of an
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incoming signal tone according to time zones. In the use of
a direct inward dialling system at general business firms,
different persons may be concerned as responders with the
direct inward dialling system generally according to time
zones such as morning, lunch time, afternoon or night. Also,
in such a case, incoming signal tones were produced at
particular EKTs in the past.
Setting of production or non-production of an
incoming signal tone at particular EKTs in the direct inward
dialling system is virtually half-fixed conventionally and it
is not easy to change such EKTs to others also according to
time zones.
It is therefore an object of the present invention
to eliminate such problems to thereby allow switching between
production and non-production of an incoming signal tone at
particular EKTs according to time zones.
SUMMARY OF THE INVENTION
In order to achieve the above object, the present
invention provides an electronic private branch exchange
comprising: a plurality of line circuits corresponding to a
like number of extension telephone sets; a plurality of main
wire trunks corresponding to a like number of main wires;
incoming signal control means for putting any particular ones
of the plurality of extension telephone sets in corresponding
relationship to each of the main wire trunks and for causing
an incoming signal from that main wire trunk to be received
at the particular extension telephone sets; means for setting
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from a certain one of the extension telephone sets a time
zone in which an incoming signal tone is to be produced at
particular ones of the extension telephone sets; and means
for sending to the particular extension telephone sets a
signal to produce an incoming signal tone at those extension
telephone sets in the time zone set by the setting means.
The incoming signal control means includes: a first memory
for storing the port numbers of the extension telephone sets
where an incoming signal from the corresponding main wire
trunk is received; and means for searching from the first
memory extension telephone sets to perform an incoming signal
processing when there is an incoming signal from the
corresponding main wire trunk. The setting means includes: a
second memory for storing information indicative of a time
zone in which an incoming signal tone is to be produced at
each extension telephone set on reception of an incoming
signal from the corresponding main wire trunk; a third memory
for storing information indicative of a time zone in which an
incoming signal tone is to be produced; means for changing
the stored contents of the third memory from a certain
extension telephone set; and means for comparing, when there
is an incoming signal for the extension telephone sets, the
contents of the second memory and the third memory and for
setting as the extension telephone set at which the incomin~
signal tone is to be produced an extension telephone set on
which the contents of the second and third memories are
equal.
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In the present invention, when there is an incoming
signal from the corresponding main wire trunk, an extension
telephone set which performs an incoming signal processing is
searched from the first memory, and data on a time zone
during which an incoming signal tone is to be sent to the
searched extension telephone set is read from the second
memory. When the read data indicative of the time zone and
the data in the third memory are equal, an incoming signal
processing is performed, inclusive of sending an incoming
signal tone to the extension telephone set. Since the
contents of the third memory are changeable, an incoming
signal processing can be performed inclusive of sending an
incoming signal tone to a different extension telephone set
by changing the contents of the third memory.
Thus according to the present invention, switching
is possible between production and non-production of an
incoming signal tone according to time zones.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a schematic of an electronic private
branch exchange;
Fig. 2 is a schematic of an electronic key
telephone;
Fig. 3 is a schematic of a memory
Fig. 4 is a flowchart showing setting of a time
zone; and
Fig. 5 is a flowchart showing transmission of an
incoming signal tone to an electronic key telephone.
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DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of the present invention will now bedescribed in detail with reference to the drawings.
Fig. 1 is a schematic of an electronic private
branch exchange according to the embodiment. A plurality of
electronic key telephones (EKTs) la - ln are connected
through line circuits (LCs) 2a - 2n to a talking channel
network (SW) 3. The network 3 is connected through main wire
trunks (TRKs) 4a - 4n to corresponding main wires (not
shown). The talk channel network 3, line circuits 2a - 2n
and main wire trunks 4a - 4n are connected through a control
bus 5 to a central processing unit (CC) 6. The central
processing unit 6 which uses data stored in a memory (MEM) 7
to perform control operations. Talking channels among
electronic key telephones la - ln and between the key
telephones la - ln and the main wires are provided by the
network 3 which transmits and receives data to and from the
central processing unit 6.
Fig. 2 is a plan view of one of the electronic key
telephones la - ln which include a handset 11, a blocking
mechanism 12, a dialling mechanism 13, a key button unit of
various service key buttons 14, a liquid crystal display
(LCD) 15, etc. The service key button unit 14 includes keys
which set and change a time zone section and a key which is
used to respond to an incoming signal from the corresponding
wire trunk circuit.
Fig. 3 shows a map of the memory (MEM) 7 which
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includes memory units (MBEXTP) 7a, (MBRNGD) 7b and (MBRGCD)
7c. The memory unit 7a stores for each of trunk numbers (T,
No) given to the corresponding trunk circuits the port
numbers (EXTPNs) of key telephones to which an incoming
signal, if any, from that one of the trunk circuits 4a - 4n
is transferred. In the memory unit 7a, a maximum of (m + 1)
key telephones at which a probable incoming signal is to be
received can be registered and stored for each trunk circuit.
In the respective areas of the memory unit 7a, the port
numbers of the key telephones and particular values (here,
FFHs) for unregistered key telephones are stored. The memory
unit 7b includes a memory map with the main wire trunk
numbers, the port numbers of the key telephones which receive
an incoming signal from the corresponding one of the main-
wire trunk circuits, and time zone sections in which incoming
signal tones are to be produced at the key telephones. In
this embodiment, one of values "00", "01", "02" is stored as
a time zone section. For example, the "00" denotes a time
zone section from 8.00 to 12.00 a.m., the "01" a time zone
from 12.00 a.m. to 1.00 p.m., and the "02" a time zone from
1.00 p.m. to 8 a.m., next morning. In the memory locations
which no key telephone numbers corresponding to each of the
trunk circuits are stored, particular values (here, FFHs) are
stored. The memory unit 7c has a value which is updated by
the key operation of a particular key telephone. The value
is one of the "00", "01" and "02" which correspond to the
values which the memory unit 7b can take. Namely, the "00"
corresponds to the time from 8.00 a.m. to 12.00 a.m., "01" to
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the time from 12.00 a.m. to 1.00 a.m., and "02" to the time
from 1.00 a.m. to 8.00 a.m., next morning.
Changing of a system time zone from a particular
key telephone will be described using a processing flow in
Fig. 4. First, a key, allocated as a ringing control key
"RCK", of the service key button unit 14 of the particular
key telephone ln is depressed (step 800). By this operation,
a signal indicative of the depression of the ringing control
key "RCK" is transmitted to CC6 via the line circuit 2n and
control bus 5. When the cèntral processing unit 6 receives
the signal indicative of the depression of the ringing
control key "RCK", it reads as the ringing control data the
value stored in the memory 7c (step 801). The central
processing unit then checks to see if the value of the
ringing data Q is ~oo~ (step 802). If so, the processing
unit 6 transmits a flash signal to the key telephone via the
control bus line 5 and the line circuit 2n in order to flash
~( ..
the diode (LED) corresponding to the control key RCK of that
telephone (step 803). In order to update the ringing control
data, the processing unit 6 adds one to the value read from
the memory 7c (step 804). It further writes the updated
value into the memory 7c (step 805). Thus the ringing
control data is updated from "00" to "01", and the light
emitting diode (LED) of the ringing control key "RCK" shows a
flashing pattern to indicate that the ringing control data is
"01", namely, the current system time zone is between 12.00
and 1.00 a.m. When the ringing control key "RCK" is
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depressed and the contents of the memory 7c are not "00", the
central processing unit 6 checks whether the contents of the
memory 7c are "01" (step 806). When the contents of the
memory 7c are "01", the central processing unit 6 sends a
steady-lighted signal to the key telephone ln via the same
path as it has sent the flash signal in order to put the LED
of the ringing control key "RCK" in the steady-lighted state
(step 807). The central processing 6 then adds one to the
memory 7c-contents to update same (step 804) and stores the
updated value in the memory 7c (step 80~). Thus, the current
system time zone is updated to the time zone from 1.00 p.m.
to 8.00 a.m., next morning and in order to display that the
current time zone is that time zone, the LED of the ringing
tone control key "RCK" of the key telephone ln takes a
pattern of steady lightening. If the memory 7c value is not
"01" when the ringing control key "RCK" is depressed, the
central processing unit 6 checks to see if the contents of
the memory 7c are "02" (step 802). If not, the processing
unit 6 ends that processing without doing any other
processing. If the contents of the memory 7c are "02", the
processing unit 6 transmits a dim-lighting signal to the key
telephone ln via the same path as that used for the
transmission of the flashing signal, in order to dimly light
the LED of the ringing control key "RCK" (step 809). The
central processing unit 6 updates the memory 7c value to "00"
(step 810) and writes the updated "00" value into the memory
7c (step 805). Thus, the current system time zone is updated
to a time zone from 8.00 a.m. to 12.00 a.m., and the LED of
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the ringing control key "RCK" is lighted in a pattern of dim
lighting in order to display that fact. As will be obvious
from the above description, the system can take and update
three kinds of time zones mentioned above by depressing the
control key "RCK" of the key telephone ln.
The transmission of an incoming signal tone to a
key telephone EKT performed when there is an incoming signal
from a trunk circuit will be described using the processing
flow of Fig. 5. Any incoming signal processing other than
the transmission of the incoming signal tone will not be
described here. Now the operations performed when there is
an incoming signal from the trunk 4b will be described. The
central processing unit 6 receives that incoming signal via
the control bus line 5 from the trunk circuit 4b. The
central processing unit 6 performs a series of incoming
signal processing operations on the corresponding key
telephones on reception of the incoming signal. The
transmission of the incoming signal tone among the incoming
signal processing operations will be performed as follows.
First, the processing unit 6 reads the head address of the
memory 7a corresponding to the trunk number (T.No) in order
to search the key telephone at which the incoming signal is
to be received (step 900). Here, if the T, No of the trunk
circuit 4b is No. 1, the head address is changed to a value
of TOPEXT. The central processing unit 6 then accesses the
head address of the memory 7b which stores the time zones for
the destination key telephones and corresponding to the trunk
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circuit at which there has been the incoming signal. (step
901). Assume here that the address data is changed to a
value of TOPRNG. In order to examine the current system time
zone, the processing unit 6 reads the stored contents
(hereinafter referred to the "~") from the memory 7c (step
902). For convenience of the subsequent processing, a
counter C (not shown) is then initialized (set to 00) (step
903). After these pre-processing operations, the central
processing unit 6 takes a new address including the address
TOPXET + the counter C count, and checks to see if there is
an electronic key telephone EKT to process the incoming
signal from the incoming trunk (step 905). If the new
address is FFH, or the contents of the counter C are m + 1
which exceeds a maximum, the processing unit ends that
processing by determining that there are no destination key
telephones or that the transmitting processing of the
incoming signal tone in the incoming signal processing has
been completed. Assume now that the address value is not FFH
and the counter C count is smaller than m + 1. At this time,
the central processing unit 6 reads the address value n
including the address TOPRNG plus the counter C count (step
906). The central processing unit checks to see if the read
value n and the previously read value ~ are equal (step 907).
If so, the processing unit 6 transmits a ringing signal to
the port of the key telephone read from the address TOPEXT to
produce an incoming signal tone at that key telephone in the
same path through which the lightening signal was sent to the
LED of the ringing control key "RCK" of that key telephone EKT.
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Thus the incoming signal tone is produced at the key
telephone the port number of which is stored at the address
TOPEXT. The central processing unit 6 then updates the
counter C value in order to perform the same processing for a
key telephone the port number of which is stored at the next
address TOPEXT (step 909). As described above, the central
processing unit 6 checks to see the necessity for
production/non-production of an signal tone for all the key
telephones corresponding to the incoming signal trunk circuit
and performs the corresponding processing operations.
Thus according to the particular embodiment, an
incoming signal tone can be produced at, and the
corresponding incoming signal can then be received at, a
different extension telephone set by changing the value set
at the memory 7c.
The present invention has been described above with
respect to an embodiment in which switching is made possible
between production and non-production of an incoming tone
according to time zones.
However, it should be of course understood that the
invention may be embodied in other specific forms without any
departure from the spirit or essential characteristics
thereof.
For example, switching between production and non-
production of an incoming tone may be possible according to
date zones or according to combinations of date zones and
time zones.
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