Fire Monitoring System and Smoke Detector
AssigneeNohmi Bosai Ltd.
InventorMasamichi Uchida
Life of this patent
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Abstract
A fire monitoring system includes a smoke detector, a first correction unit obtaining a first corrected value by multiplying a difference value between a reference value and a detection value by a first correction coefficient, a first conversion unit converting the first corrected value into a first smoke density, and a fire determination unit determining occurrence of a fire event based on the first smoke density. The first correction coefficient is set on an increase side corresponding to an increase in a rate of change of the reference value to an initial reference value, and an upper limit value is set for the first correction coefficient.
Claims9
A fire monitoring system, comprising:
- a smoke detector including a light emitting element and a light receiving element provided in a smoke detection chamber, the smoke detector being configured to output a detection value of the light receiving element corresponding to a smoke density in the smoke detection chamber;
- a fire alarm control unit configured to receive output from the smoke detector;
- a reference value storage unit configured to store a reference value, the reference value being the detection value of the light receiving element when the smoke density is zero;
- a first correction unit configured to obtain a first corrected value by multiplying a difference value between the reference value and the detection value of the light receiving element by a first correction coefficient;
- a first conversion unit configured to convert the first corrected value into a first smoke density;
- and
- a fire determination unit configured to determine occurrence of a fire event based on a result of comparison between the first smoke density and a fire threshold value,
- wherein the first correction coefficient is set on an increase side corresponding to an increase in a rate of change of the reference value with respect to an initial reference value, the initial reference value being an initial value of the reference value, and
- wherein an upper limit value is set for the first correction coefficient.
A smoke detector, comprising:
- a light emitting element and a light receiving element provided in a smoke detection chamber,
- a reference value storage unit configured to store a reference value, the reference value being a detection value of the light receiving element when the smoke density is zero;
- a first correction unit configured to obtain a first corrected value by multiplying a difference value between the reference value and the detection value of the light receiving element by a first correction coefficient;
- a first conversion unit configured to convert the first corrected value into a first smoke density;
- and
- a fire determination unit configured to determine occurrence of a fire event based on a result of comparison between the first smoke density and a fire threshold value,
- wherein the first correction coefficient is set on an increase side in accordance with an increase in a rate of change of the reference value with respect to an initial reference value, the initial reference value being an initial value of the reference value, and
- wherein an upper limit value is set for the first correction coefficient.
Dependencies are inferred from the claim text.