Patent ID: 7998419

Claim:
An ion generator, comprising: ion generation means for generating positive ions and negative ions; temperature and humidity detection means for detecting a temperature and a humidity in a room; and control means for determining whether the room is in a first state in which the detected temperature and the detected humidity are equal to or higher than a first temperature and a first humidity respectively, or a second state in which the detected temperature and the detected humidity are equal to or lower than a second temperature and a second humidity respectively, or in a third state, the temperature of the third state being between the first temperature and the second temperature, the humidity of the third state being between the first humidity and the second humidity, the first state and the second state being determined based solely on the detected temperature and the detected humidity in the room, and controlling the ion generating means to generate a larger amount of positive ions and negative ions when the room has been determined to be in the first state or in the second state as compared to when the room has been determined to be in the third state, and to selectively generate one of only negative ions or smaller amount of positive ions and negative ions when the room has been determined to be in the third state, said second temperature being lower than said first temperature, and said second humidity being lower than said first humidity.