Private swimming pool's perimeter safety system for preventing drowning of infant, has posts, and slave post including locking device connected to transmitter and receiver so that downstream beam is synchronized with upstream beam

摘要

The system has slave and receiver posts (3, 3A), and a master post (2) including a clock (12) connected to a transmitter (4) transmitting an upstream electromagnetic radiation beam (6) e.g. laser beam, that is under a periodic discontinuous form. The beam has a transmission absence time complementary to/lower than a transmit time. The post (3) has a transmitter (5) transmitting a downstream electromagnetic radiation beam (7) under a periodic discontinuous form and has a locking device (13) connected to its transmitter (5) and receiver (8) so that the beam (7) is synchronized with the beam (6).