专利检索 ap:("Fumikazu Hamatani" OR "Mikihiro Ichikawa" OR "Yuji Tanaka") AND inv:"Mikihiro Ichikawa" 第 1 页

1.

发明授权
Control circuitry for key telephone apparatus 失效
标题翻译：关键电话设备的控制电路

公开(公告)号：US4081625A

公开(公告)日：1978-03-28

申请号：US728514

申请日：1976-10-01

申请人： Fumikazu Hamatani , Mikihiro Ichikawa , Yuji Tanaka

发明人： Fumikazu Hamatani , Mikihiro Ichikawa , Yuji Tanaka

IPC分类号： H04Q3/58 , H04M9/00 , H04M1/72

CPC分类号： H04M9/005

摘要： The disclosure is for key telephone system line control circuitry which provides telephone station line status signals for central office ring, busy, idle and station hold conditions by means of a single control line.