| 摘要 |
PROBLEM TO BE SOLVED: To provide a transmitter for a tire state monitoring device and the tire state monitoring device capable of preventing a changeover from the present operation mode to other operation modes according to atmospheric pressure change in air transportation for example and promptly transmitting data in an unusual state during use. SOLUTION: A third threshold changing over from a sleep mode to an unusual mode is set to 20 kPa/min and a first threshold changing over from a usual mode to the unusual mode is set to 5 kPa/min. Therefore, the changeover of an operation mode of a transmitter 30 from the sleep mode to the unusual mode caused by the atmospheric pressure change in air transportation can be prevented. After the transmitter 30 is attached to the inside of the tire, if air is filled so that the changing amount of air pressure inside the tire becomes 20 kPa/min or more, the operation mode of the transmitter 30 is changed over from the sleep mode to the unusual mode. After that, if the changing amount of the air pressure inside the tire becomes less than 5 kPa/min, the operation mode of the transmitter 30 is changed over from the unusual mode to the usual mode. COPYRIGHT: (C)2003,JPO
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