| 摘要 |
PURPOSE:To allow transfer to both a specified and an unspecified transfer destination freely by providing a coupling switch which self-holds a call state during transfer to the unspecified destination telephone set in a telephone transfer device. CONSTITUTION:Transfer between a calling telephone set A and the specified detination telephone device D is allowed by using the telephone transfer device 5, and the manual coupling switch 7 is provided between a terminating telephone set B and an originating telephone set C to enable transfer to the unspecified detination telephone set E. For the transfer from the telephone set A to the unspecified destination telephone set E, the coupling switch is closed while the terminating telephone set B and originating telephone set are both placed in off- hook state. Through the closed path of the coupling switch 7, the transfer device 5 couples the telephone sets B and C with each other to allow self-holding operation, thereby placing the calling telephone set A and unspecified destination telephone set E in a call state. After the call, the couping switch 7 turns off automatically. |
