Title:
PUSHBUTTON TELEPHONE SET
Document Type and Number:
Japanese Patent JP3451905
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To improve the operating convenience by allowing the user to surely identify a channel operating state in the case of using an ISDN channel which is assigned to an external line key and an external line lamp of a telephone set.
SOLUTION: In the case that a master set 1 contains an ISDN channel #1 and one dial-in number is set, it is taken into account that two incoming calls consisting of one dial-in incoming call and one global incoming call or two global incoming calls may take place simultaneously in the ISDN channel. Therefore two external keys and external lamps are assigned to telephone sets 3 (31-3n) for global incoming calls and other two external keys and external lamps for dial-in incoming calls. At the arrival of an incoming call, a corresponding external line lamp turns on. When two incoming calls take place simultaneously, an idle external line lamp turns on to indicate its busy state.
Inventors:
Katsuhiko Onozuka
Application Number:
JP29393797A
Publication Date:
September 29, 2003
Filing Date:
October 27, 1997
Export Citation:
Assignee:
Tamura Electric Co., Ltd.
International Classes:
H04M3/42; H04M1/00; H04M1/253; H04Q3/58; (IPC1-7): H04Q3/58; H04M1/00; H04M3/42
Domestic Patent References:
| JP5130661A | ||||
| JP468997A | ||||
| JP3160896A | ||||
| JP2158225A | ||||
| JP7177545A | ||||
| JP5284558A |
Attorney, Agent or Firm:
Masaki Yamakawa