Abstract:
The disclosed ceiling mountable passive infrared intrusion detection system includes a field forming mirror assembly and a focusing mirror assembly cooperative to provide a field of view having plural first vertical curtains, a generally disc-shaped horizontal second curtain, and a generally conical downwardly directed third curtain. In one embodiment, first and second conical field forming mirrors are cooperative with different and spaced-apart spherical focusing mirrors to provide the horizontal curtain and the downwardly directed conical curtain. An unbalanced detector is disclosed that cooperates with the energy pattern received from the conical field forming mirrors to signal intruder presence. In another embodiment, first and second pluralities of planar field forming mirrors are cooperative with the different and spaced-apart spherical focusing mirrors to respectively provide a first plurality of substantially horizontal finger beams and a second plurality of plural downwardly directed finger beams. In this embodiment, a balanced detector is disclosed that cooperates with the energy pattern received from the first and second pluralities of finger beams to signal intruder presence.
Abstract:
A modular transceiver head including cooperative cover and base members operable as a transmitter or as a receiver of infrared energy. The cover member includes a window defining a comparatively wide field of view in azimuth and in elevation. An optical train including a gimbaled specular member that is mounted to the base member readily allows both rough and fine adjustment of the pointing direction of the specular member anywhere within the field of view of the cover member window. A controller including a processor is coupled to a transceiver head pair respectively operative as a transmitter and as a receiver of infrared energy to controllably project a beam of infrared energy therebetween through a protected region. The controller is operative to de-sensitize the beam against potential electrically interferring effects present along the beam path. The controller is periodically operative in a self-test mode to reduce the intensity of the projected-beam to simulate a smoke condition. The controller is periodically operative in a self-compensation mode to compensate for long and short term beam degredation effects such as pollution variation normally encountered along the beam path arising in the normal operation of the protected region and to compensate for film build-up on the elements of the transceiver head optical trains. The controller is cooperative with a watch-dog timer to monitor its own operating state. Plural alalrm thresholds are operator selectable to provide enhanced confidence detection, and particularized signal indications are provided to readily and quickly identify possible alarm and trouble conditions.
Abstract:
Apparatus for sensing smoke in a duct includes a housing with inlet and outlet ports and a flow chamber which directs gas flow on a path between the ports and to and from a smoke detector. A vaned rotor on the path is visible through a window in the housing gives a visual indication of the existence or nonexistence and direction of gas flow and thus whether or not normally flowing duct gas is being sensed.
Abstract:
A modular transceiver head including cooperative cover and base members operable as a transmitter or as a receiver of infrared energy. The cover member includes a window defining a comparatively wide field of view in azimuth and in elevation. An optical train including a gimbaled specular member that is mounted to the base member readily allows both rough and fine adjustment of the pointing direction of the specular member anywhere within the field of view of the cover member window. A controller including a processor is coupled to a transceiver head pair respectively operative as a transmitter and as a receiver of infrared energy to controllably project a beam of infrared energy therebetween through a protected region. The controller is operative to de-sensitize the beam against potential electrically interfering effects present along the beam path. The controller is periodically operative in a self-test mode to reduce the intensity of the projected-beam to simulate a smoke condition. The controller is periodically operative in a self-compensation mode to compensate for long and short term beam degradation effects such as pollution variation normally encountered along the beam path arising in the normal operation of the protected region and to compensate for film build-up on the elements of the transceiver head optical trains. The controller is cooperative with a watch-dog timer to monitor its own operating state. Plural alarm thresholds are operator selectable to provide enhanced confidence detection, and particularized signal indications are provided to readily and quickly identify possible alarm and trouble conditions.
Abstract:
The access control system according to the present invention provides for the centralized control of the system operating parameters, including all times, access codes, alarms, error messages, and pass-coded indications. The access control system communicates with a plurality of remote card readers, at which point the user enters a code to gain entry into the protected areas. The access control system according to the present invention selectively stores limited information at each card reader location, wherein access control is still maintained, even if the central data system becomes inoperative. Moreover, the communication between the central data system and the plurality of card readers includes data transfers through a plurality of subsystems, each having a data processing program therein. The system according to the present invention provides for efficient communication between asynchronous operating subsystems through the controlled use of a first-in-first-out (FIFO) data register pair. In this manner, each subsystem according to the present invention operates independently until a data transfer is initiated, causing the other operations to be suspended to permit the transfer of data. The FIFO allows for data to be transferred at different rates between subsystems, allowing freedom in subsystem operation and data transfer rates.
Abstract:
A modular transceiver head including cooperative cover and base members operable as a transmitter or as a receiver of infrared energy. A controller including a processor is coupled to a transceiver head pair respectively operative as a transmitter and as a receiver of infrared energy to controllably project a beam of infrared energy therebetween through a protected region. The controller is periodically operative in a self-test mode to reduce the intensity of the projected-beam to simulate a smoke condition. Plural alarm thresholds are operator selectable to provide enhanced confidence detection, and particularized signal indications are provided to readily and quickly identify possible alarm and trouble conditions.
Abstract:
The disclosed steerable mirror assembly and cooperative housing for a ceiling mountable passive infrared intrusion detection system of the present invention includes first and second relatively rotatable field forming mirrors cooperative with a focusing mirror to provide first and second substantially curtain-like fields of view at any selected pointing directions through 360.degree. of azimuth. The field forming mirrors have a preselected non-constant radius of curvature selected to provide uniform detection sensitivity at any range within the fields of view of the several curtains. A modular housing is disclosed having cooperative, releasably assemblable components that allows ready in-the-field installation, and subsequent maintenance and troubleshooting. The housing includes a tamper switch that is operative upon an unauthorized tampering with the housing after installation to provide a signal indication of a possible system deactivization attempt.
Abstract:
Test apparatus for a wireless system is provided in which an audible annunciation is produced which is an accurate indication of the measured received signal strength. A signal is derived from the receiver which is representative of the signal strength and which is employed to activate a speech synthesizer which provides annuciation of each of a range of digits, each digit annunication representing a predetermined increment of received signal strength.
Abstract:
A controller including a processor is coupled to a transceiver head pair respectively operative as a transmitter and as a receiver of infrared energy to controllably project a beam of infrared energy therebetween through a projected region. The controller is operative to de-sensitize the beam against potential electrically interferring effects present along the beam path. Plural alarm thresholds are operator selectable to provide enhanced confidence detection, and particularized signal indications are provided to readily and quickly identify possible alarm and trouble conditions.