PROBLEM TO BE SOLVED: To detect a change in a direction of a sensor head and allow a calling of abnormality to be made without complicating a structure of the sensor head.SOLUTION: A calling control part 22 makes a normal calling when a signal is detected both by a sound sensor 5 and a proximity sensor 6 disposed to a sensor head arranged at the tip of a flexible arm, and makes a calling of abnormality to notify that a direction of the sensor head has changed when a signal is detected only by the sound sensor 5 so that if the direction of the sensor head is correct when a care-receiver produces a sound, a normal calling is made, and if the direction has been changed, a calling of abnormality is made, thereby eliminating the need to provide a direction sensor such as an acceleration sensor to the sensor head, in addition to the sound sensor 5 and the proximity sensor 6.SELECTED DRAWING: Figure 2
