Devices, methods, and systems for a self-testing fire sensing device are described herein. One device includes an adjustable particle generator and a variable airflow generator configured to generate an aerosol density level, an optical scatter chamber configured to measure a rate at which the aerosol density level decreases after the aerosol density level has been generated, and a controller configured to compare the measured rate at which the aerosol density level decreases with a baseline rate, and determine whether the self-testing fire sensing device requires maintenance based on the comparison of the measured rate at which the aerosol density level decreases and the baseline rate.

Described, herein, relates to a system of and method for the safe and rapid mounting of an environmental sensor (e.g., a smoke detector) onto an elevated support surface (e.g., a wall, a post, or a ceiling). Accordingly, the installation harness may include a housing and a wall mount. During use, the wall mount may be configured to be affixed to the elevated support surface. Additionally, the housing may be configured to selectively couple to the wall mount through a connector extension, securing the housing to the wall mount. Subsequent to a user coupling the housing to the mount, the environmental sensor may be in electrical communication with a power source, via at least one male ring connector being electrically coupled to its respective at least one female ring connector.

This application is directed to a home monitoring and control system including a doorbell installed at a door of a home. The doorbell has a button configured to, upon being touched, depressed or activated, wirelessly initiate a first communication to indicate presence of a person at the door. The doorbell also has a camera configured to capture video data within a field of view, and a processor configured to cause a communication component to enable the first communication and wirelessly stream via a remote server the video data captured by the camera to a monitoring device associated with an occupant of the home. A rechargeable battery is coupled to a housing wire and configured to be charged via the housing wire, and the doorbell is configured to charge and discharge the rechargeable battery based on power usage of the doorbell.

Various embodiments of the teachings herein include a measurement chamber for a smoke detection unit of a smoke detector. The measurement chamber may include: at least a passage for smoke to be detected; and a measurement chamber cover with angular light trap structures on an inside of the measurement chamber. The angular light trap structures are shaped to follow the compact-design principle of a Fresnel stepped lens.

Various embodiments of the teachings herein include a measurement chamber for a smoke detection unit of a smoke detector. The measurement chamber may include: at least a passage for smoke to be detected; and a measurement chamber cover with angular light trap structures on an inside of the measurement chamber. The angular light trap structures are shaped to follow the compact-design principle of a Fresnel stepped lens.

Devices, methods, and systems having insect guards in devices and systems for aspirated smoke, gas, or air quality monitoring are described herein. One aspirated smoke, gas, or air quality monitoring unit includes a detector module that includes at least one particulate sensing chamber within the detector module and an air inlet connecting the sampling tube to the particulate sensing chamber allowing communication of air from the sampling tube to the particulate sensing chamber; and a spiral shaped insect guard positioned within the inlet.

A fire detection apparatus 1F for detecting a fire in a monitored area, the fire detection apparatus 1F being attached to an installation surface of an installation object, the fire detection apparatus 1F comprises a detection space 60F in which detection of a detection target is performed; an incidence suppressing unit that inhibits ambient light from entering the detection space 60F, the incidence suppressing unit being able to allow a gas containing the detection target to flow into and out of the incidence suppressing unit; an accommodating unit that accommodates the incidence suppressing unit, the accommodating unit being able to allow the gas to flow into and out of the accommodating unit; and a light shielding wall 140F provided to surround the incidence suppressing unit on an inside of the accommodating unit, wherein the incidence suppressing unit includes a first incidence suppressing unit that covers a part of the detection space 60F, and a second incidence suppressing unit provided on an installation surface side of the first incidence suppressing unit, the second incidence suppressing unit covering another part of the detection space 60F, and the light shielding wall 140F is configured such that the light shielding wall overlaps a boundary between the first incidence suppressing unit and the second incidence suppressing unit when viewed in a direction orthogonal to the installation surface.

Example implementations include a smoke detector comprising a smoke chamber; an LED that generates light in the smoke chamber; a photodetector configured to detect whether a threshold amount of light is scattered by smoke particles in the smoke chamber; and one or more self-testing components configured to re-direct the light from the LED toward the photodetector for self-testing the LED and the photodetector. Some further implementations include one or more masking self-test components configured external to the smoke chamber to direct light from outside the smoke chamber into the smoke chamber and toward the photodetector for determining whether the smoke detector has been masked. Some further example implementations include a method comprising controlling one or more self-testing components of a smoke detector to re-direct at least a portion of light from an LED toward a photodetector; and determining whether the photodetector causes an alarm trigger in response to the controlling.

Example implementations include a smoke detector comprising a smoke chamber; an LED that generates light in the smoke chamber; a photodetector configured to detect whether a threshold amount of light is scattered by smoke particles in the smoke chamber; and one or more self-testing components configured to re-direct the light from the LED toward the photodetector for self-testing the LED and the photodetector. Some further implementations include one or more masking self-test components configured external to the smoke chamber to direct light from outside the smoke chamber into the smoke chamber and toward the photodetector for determining whether the smoke detector has been masked. Some further example implementations include a method comprising controlling one or more self-testing components of a smoke detector to re-direct at least a portion of light from an LED toward a photodetector; and determining whether the photodetector causes an alarm trigger in response to the controlling.

The present disclosure relates to aspirating smoke detectors (ASD). In an ASD, ambient air is aspirated and is fed to a fire detector unit for determining a signal level. For normal operation, the suction power is set to a nominal airflow value and this is increased from a minimum signal level value in order to shorten the transport time of aspirated smoke through the suction pipe to the fire detector unit. In some embodiments, an interruption signal provided for normal operation is output if the airflow exceeds an upper limit value for a minimum period. Independently thereof, the suction power is increased from the minimum signal level value only to the extent that the airflow does not exceed the upper limit value. Or, regardless thereof, the suction power is increased only for a timespan smaller than the minimum period in which the airflow exceeds the upper limit value.