JPS56166695A - Incoming call answering system - Google Patents

Abstract

PURPOSE:To facilitate manufacture of a button answering unit while simplifying the constitution of a relay other than a relay for monitoring button operation, by controlling the operation of a connection line between a telephone set and the button answering unit through the relay for monitoring button operation. CONSTITUTION:A button answering unit BTU is provided corresponding to a button-attached telephone set TEL, and the unit BTU and telephone set TEL are connected together via a call line and control line having a hook switch contact HS and button contacts AK. This unit BTU is provided with a relay A for monitoring a telephone set loop, which operates through the telephone set loop, via a channel by the origination of the telephone set TEL. Further, a relay H for monitoring button operation which operates with information sent to the control line through the button operation of the telephone set TEL is provided, and the relays A and H operate in cooperation to discriminate whether the origination of the telephone set TEL is that answering a trunk-line incoming call or not. Then, a connection line C1 between the telephone set TEL and unit BTU is used as an operation control line for the relay H, and manufacture of the relay A and a relay HA for discriminating a trunk-line incoming answer connection is facilitated.