Multiple alarm system with low battery detection for controlling transmission and reception of an alarm signal

• US 8,514,091 B2
• Filed: 03/17/2009
• Issued: 08/20/2013
• Est. Priority Date: 04/28/2008
• Status: Active Grant

• Current Assignee: Hochiki Corporation
• Original Assignee: Hochiki Corporation
• Inventors: Egawa, Yoshitaka
• Primary Examiner(s): HOFSASS, JEFFERY A
• Application Number:
  US12/936,989
• Publication Number:
  US 20110037603A1
• Time in Patent Office: 1,617 Days
• Field of Search: 340/539.1, 340628-630, 3406361-63619, 340/506
• US Class Current: 340/636.1
• CPC Class Codes: G08B 17/00 Fire alarms; Alarms responsive to explosion
• CPC Class Codes: G08B 17/113 Constructional details
• CPC Class Codes: G08B 25/009 Signalling of the alarm condition to a substation whose identity is signalled to a central station, e.g. relaying alarm signals in order to extend communication range
• CPC Class Codes: G08B 29/181 due to failing power supply

Abstract

The alarm device of the present invention includes a battery power supply; a sensor section that outputs an anomaly detection signal in the case of detecting an anomaly; an alert section that outputs an alarm based on the anomaly detection signal; a reception circuit section that discontinuously receives an event signal from another alarm device at every predetermined reception cycle; a transmission circuit section that transmits an event signal to the other alarm device in a transmission time that is at least the predetermined reception cycle; an anomaly monitoring section that, when the sensor section has detected an anomaly, causes the alert section to output the anomaly alarm based on the anomaly detection signal and causes the transmission of an event signal relating to the anomaly of the alarm device to the other alarm device by the transmission circuit section, and on the other hand, when the reception circuit section has received from the other alarm device an event signal relating to an anomaly of the other alarm device, causes the alert section to output the anomaly alarm; and a low battery monitoring section that, upon detecting a voltage drop of the battery power supply, causes a low battery alarm of the alarm device to be output by the alert section, and stops the transmission and reception of event signals in the transmission circuit section and the reception circuit section.

Claims

1. An alarm device comprising:

a battery power supply;

a sensor section that outputs an anomaly detection signal in the case of detecting an anomaly;

an alert section that outputs an alarm based on the anomaly detection signal;

a reception circuit section that discontinuously performs a reception operation to receive an event signal from another alarm device at every predetermined reception cycle consisting of a reception operation time and a sleep time;

a transmission circuit section that transmits an event signal to the other alarm device in a transmission time that is longer than the predetermined reception cycle;

an anomaly monitoring section that, when the sensor section has detected an anomaly, causes the alert section to output a linked source anomaly alarm based on the anomaly detection signal and causes the transmission of an event signal relating to the anomaly of the alarm device to the other alarm device by the transmission circuit section, and when the reception circuit section has received from the other alarm device an event signal relating to an anomaly of the other alarm device, causes the alert section to output a linked destination anomaly alarm; and

a low battery monitoring section that, upon detecting a voltage drop of the battery power supply, causes a low battery alarm of the alarm device to be output by the alert section,

wherein the battery power supply supplies a power to a circuit provided with at least the transmission circuit section and the reception circuit section, during a normal monitoring state,

the low battery monitoring section detects the low battery when a voltage of the battery power drops to a limit voltage at which the alarm device can maintain an alert state over a predetermined remaining time, and upon detecting the low battery, stops a supply of the power to the reception circuit section and the transmission circuit section while maintaining the supply of the power to other circuit sections so that the alarm device functions as the alarm device which does not perform linked alarm output with the other alarming device over the predetermined remaining time.

4. The alarm device according to claim 1, wherein the reception circuit section sets the predetermined reception cycle based on an average consumption current ensuring a predetermined battery life.

2. An alarm device comprising:

a battery power supply;

a sensor section that outputs an anomaly detection signal in the case of detecting an anomaly;

an alert section that outputs an alarm based on the anomaly detection signal;

a reception circuit section that discontinuously performs a reception operation to receive an event signal from another alarm device at every predetermined reception cycle;

a transmission circuit section that transmits an event signal to the other alarm device in a transmission time that is longer than the predetermined reception cycle;

an anomaly monitoring section that, when the sensor section has detected an anomaly, causes the alert section to output the anomaly alarm based on the anomaly detection signal and causes the transmission of an event signal relating to the anomaly of the alarm device to the other alarm device by the transmission circuit section, and when the reception circuit section has received from the other alarm device an event signal relating to an anomaly of the other alarm device, causes the alert section to output the anomaly alarm;

a low battery monitoring section that causes the output from the alert section of a low battery alarm that announces a voltage drop of the alarm device and the other alarm device; and

a transmission and reception time control section that controls the transmission time of the transmission circuit section and the predetermined reception cycle of the reception circuit section;

wherein when a voltage drop of the battery power supply is detected, the low battery monitoring section causes the alert section to output a low battery alarm of the alarm device, and causes the transmission circuit section to transmit an event signal relating to the voltage drop of the alarm device to the other alarm device, and the transmission and reception time control section changes the predetermined reception cycle of the reception circuit section to a long reception cycle that is longer than the predetermined reception cycle; and

when an event signal relating to a voltage drop of the other alarm device is received from the other alarm device, the low battery monitoring section causes the alert section to output a low battery alarm of the other alarm device, and the transmission and reception time control section changes the transmission time of the transmission circuit section to a time equal to or greater than the long reception cycle.

3. The alarm device according to claim 2, wherein the low battery monitoring section detects the voltage drop when the battery voltage has dropped to a limit voltage at which the alarm device can maintain an alert state over a predetermined remaining time.