04009337 is referenced by 95 patents and cites 11 patents.

A small scale electronic telephone exchange system of stored program control type having a plurality of trunks and a central computer has been disclosed. The trunks function to process the real time operation and, therefore, the central computer does not need to operate on a real time basis. The central computer always scans the condition of the trunks and the subscriber's telephone terminals and, upon detecting the change of said condition, it analyzes said change and performs the necessary process for said change. The present exchange system provides many new services but the cost of the system is reasonable.

Title
Stored program control type electronic exchange system
Application Number
5/513815
Publication Number
4009337
Application Date
October 10, 1974
Publication Date
February 22, 1977
Inventor
Susumu Sugou
Tokyo
JA
Kazuo Suzuki
Tokyo
JA
Tetsuya Matsuno
Tokyo
JA
Akira Imada
Tokyo
JA
Akira Ogishima
Tokyo
JA
Shigeo Sakai
Tokyo
JA
Agent
Kenyon & Kenyon
Assignee
Oki Electric Industry Company
JA
IPC
H04M 3/42
H04Q 3/54
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