Alarm and security system for building with gas pipes - has throughflow indicator in by=pass line and with non-return valve operating switch for magnetic valve and optical signal generator

摘要

The warning and safety device serves a building gas line (4) divided into a large section main line (7) and a smaller bypass (8) merging to form the service line (2) in the building. The line is opened and closed by a magnetic valve (14) downstream of the section (7, 8) junction (13). A flow recorder (9) in the by-pass shuts this off by a non-return valve which opens for flow against slight backpressure and connects to a switch (10). The switch is actively connected to the magnet valve via time delay and switching relays (18, 17) and also to an optical (20) and/or acoustic (21) signal generator. A non-return valve in the main line opens in a flow sense against backpressure greater than that opposing the valve in the by-pass. A flame monitor (16) at the consumer end (3) connects to the signal generators via relays so that, if flame absence is reported during gas flow, the magnet valve slams shut and a signal is produced. USE/ADVANTAGE - Gas services. Flame monitor signals absence is gas flow to shut off line as explosion guard.