CHEST UNIT FOR DETECTING AND TRANSMITTING HEARTBEAT SIGNAL

PROBLEM TO BE SOLVED: To provide a chest unit 1 the battery and the circuit capsule of which can be replaced while keeping sufficient waterproof property, with respect to the unit 1 which is mounted to a human chest and detects and transmits a heartbeat signal. SOLUTION: A chest unit holder 10 is formed integrally with flexible electrodes 11 and 12 for detecting heartbeat signals and is provided with a hollow part having an opening into which the circuit capsule 18 incorporating the battery is to be fitted closely. The opening is formed on the side, which is not in contact with the human chest, of the holder 10. When the capsule 18 is fitted into the hollow part, terminals 21 and 22 provided at the capsule 18 and the electrodes 11 and 12 of the unit 1 are conducted to detect and transmit the heartbeat signals. After the transmitted heartbeat signals are received by a wrist unit 50, a heartbeat rate is displayed from the heartbeat signals.