Title:
トンネル坑内非常警報システム
Document Type and Number:
Japanese Patent JP6901952
Kind Code:
B2
Abstract:
To provide an intra-tunnel emergency alarm system enabling a discoverer to appropriately and reliably report occurrence of an emergency in the event that the emergency occurs in a tunnel construction site.SOLUTION: The intra-tunnel emergency alarm system includes plural pieces of signal relay means 10 that relay and transmit a signal through wireless communication, signal transmitting/receiving means 20 capable of transmitting or receiving a signal within a predetermined reachable range from each of the pieces of signal relay means 10 by employing wireless communication whose directivity is lower than that of the wireless communication employed between the pieces of signal relay means 10, and a portable information terminal 30 that is carried by a worker, can transmit or receive a signal to or from the signal transmitting/receiving means 20, and can originate an alarm signal.SELECTED DRAWING: Figure 1
Inventors:
Yuji Arai
Application Number:
JP2017201501A
Publication Date:
July 14, 2021
Filing Date:
October 18, 2017
Export Citation:
Assignee:
MAEDA CORPORATION
International Classes:
G08B25/00; A62B3/00; G08B17/00; G08B27/00
Domestic Patent References:
| JP2000023258A | ||||
| JP2008301217A | ||||
| JP2008165660A | ||||
| JP2017068612A | ||||
| JP2000048289A | ||||
| JP2005050109A | ||||
| JP2017038698A | ||||
| JP2003318919A | ||||
| JP2008289126A |
Attorney, Agent or Firm:
Yoshihide Ogawa