Title:
FIRE ALARMING EQUIPMENT
Document Type and Number:
Japanese Patent JP3140531
Kind Code:
B2
Abstract:
PURPOSE: To improve the reliability of signal transmission and to make it possible to immediately detect the generation of abnormality such as disconnection by loop-connecting a tire receiver to a main repeater, normal repeaters and plural terminals such as fire sensors by a more up-to-date loop type signal line.
CONSTITUTION: One fire receiver or one terminal simultaneously sends signals to a main loop signal line and a sub-loop signal lines whose transmitting directions are mutually opposed and the other fire receiver or terminal receives the signals respectively transmitted through the main loop signal line and the sub-loop signal line by MR and SR terminals and detects a difference between respective receiving times to detect the existence of transmission abnormality, so that the abnormality can be immediately detected. Since the fire receiver or terminal detecting the abnormality immediately connects the main loop signal line to the sub-loop signal line to form a signal folding route and transmits signals to all loop signal lines other than the abnormality generating point, the reliability of signal transmission can be improved.
Inventors:
Akira Igarashi
Takashi Kobayashi
Akio Sekiji
Takashi Kobayashi
Akio Sekiji
Application Number:
JP1917792A
Publication Date:
March 05, 2001
Filing Date:
February 04, 1992
Export Citation:
Assignee:
Nomi Disaster Prevention Co., Ltd.
International Classes:
G08B25/01; G08B26/00; G08B29/16; G08B17/00; (IPC1-7): G08B25/01; G08B17/00; G08B26/00
Domestic Patent References:
| JP228798A | ||||
| JP5483396A | ||||
| JP6221347A |
Attorney, Agent or Firm:
Soga Doteru (6 people outside)