1. Field of the Invention
The present invention relates to a room air conditioning system in an air conditioner, which includes at least four horizontal vanes (flaps) in blow-off openings and can independently change vertical angles of airflows.
2. Description of the Related Art
Unexamined Japanese Patent Publication No. 2011-099609 and Japanese Patent No. 5,310,792 disclose conventional examples of a configuration of an indoor unit in an air conditioner which is to be installed on the ceiling in a room.
The first indoor unit disclosed in PTL1 includes a controller and a human body sensor. If the human body sensor detects the presence of a person when the indoor unit starts a heating operation, the controller controls the horizontal flap in the blow-off opening that corresponds to the target area in which the detected person is present. In this way, the controller suppresses air from being directly blown into the person.
Similar to the controller in PTL1, human body sensors in the second indoor unit disclosed in PTL2 detect whether persons are present below the respective blow-off openings. If any of the human body sensors detects the presence of a person, the controller controls one of a plurality of vanes which corresponds to the target area in which the detected person is present such that air flows horizontally within this target area.
The human body sensor in the first indoor unit in PTL 1 has a rotatable opening section, which rotates when the human body sensor detects whether persons are present within the respective target areas. The above second indoor unit has a human body sensor assembly made up of the human body sensors that detect whether persons are present within the respective target areas.
Unfortunately, both the human body sensors in the first and second indoor units need to detect whether persons are present within as many as four target areas. In which case, the structure of the human body sensors may be complex and thus expensive.