A method of determining at least one point of entry of smoke into a smoke detection system, the system having a sampling pipe network including at least one sampling pipe and a plurality of sampling inlets through which an air sample can enter the at least one sampling pipe of the smoke detection system for analysis by a particle detector, said method including: determining a volume of sample air that has passed through at least part of the smoke detection system since a predetermined event or a value corresponding to said volume; and determining through which sampling inlet of the plurality of sampling inlets the smoke entered the smoke detection system based, at least in part, on the determined volume or value. Systems for implementing such a method and related methods are also described.
G01F 1/66 - Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
G08B 17/10 - Actuation by presence of smoke or gases
A method of particle detection in an aspirated particle detection system, the system having a sampling pipe network and a particle detector. The sampling pipe network includes at least one sampling pipe in fluid communication with the particle detector, a plurality of sampling inlets through which sample air can enter the at least one sampling pipe, and an opening in the at least one sampling pipe upstream of the plurality of sampling inlets, wherein the opening has lower flow impedance than any one of the sampling inlets. The method includes drawing sample air to the particle detector through the air sampling network; analysing the sample air with the particle detector; entering an amplification phase, in the event that a concentration of particles in the sample air greater than a predetermined threshold is detected, to create a plurality of sample air packets in the sampling pipe, wherein each sample air packet corresponds to a sampling inlet and includes an amplified concentration of air drawn from the corresponding sampling inlet; transporting the sample air including the plurality of sample air packets through the sampling pipe to the particle detector; and determining through which sampling inlet any particles entered the particle detection system.
G01N 1/26 - Devices for withdrawing samples in the gaseous state with provision for intake from several spaces
G01N 35/08 - Automatic analysis not limited to methods or materials provided for in any single one of groups Handling materials therefor using a stream of discrete samples flowing along a tube system, e.g. flow injection analysis
G08B 17/10 - Actuation by presence of smoke or gases
A particle detector, e.g. a smoke detector is described. In one form the detector includes a detection chamber and radiation source emitting a single beam of radiation. The detector also includes a radiation receiving system and an imaging system arranged to receive radiation from a common region of interest. Methods and systems for analysing the output of a particle detector are also disclosed.
An air sampling system (10, 110) for a low-temperature space (12) is disclosed. The air sampling system (10, 110) includes: an air sampling pipe (16) for passing sampling air to an air sampling device (2); and a sampling conduit (20, 120) extending from the low-temperature space (12) to outside the low-temperature space (12). The sampling conduit (20, 120) is connected to the sampling pipe (16), wherein the sampling conduit (20, 120) is selectively accessible from outside the low-temperature space (12) for removal of ice build-up within the sampling conduit (20, 120). Also disclosed is a kit for an air sampling system. Also disclosed is a method, computing system, air-sampling device and air monitoring system that evaluates an air sampling network.
A particle detection system (10) including a particle detector (16) in fluid communication with at least two sample inlets (14, 24) for receiving a sample flow from a monitored region. The particle detector (16) includes detection means for detecting the level of particles within the sample flow and outputting a first signal indicative of the level of particles within the sample flow. A flow sensor (30) is located downstream of the sample inlets (14, 24) for measuring the flow rate of the sample flow and outputting a second signal indicative of the flow rate of the sample flow. At least a first sample inlet (34) is normally open to the monitored region for receiving at least part of the sample flow. At least a second sample inlet (36) is normally closed to the monitored region but is openable to the monitored region in response to a change in environmental conditions in the monitored region. The particle detection system (10) further includes processing means adapted for receiving the first and second signals and comparing the first signal to a predetermined threshold level and comparing the second signal to a predetermined threshold flow rate, and generating an output signal based on the respective comparisons of the first and second signals. A method of particle detection is also described.
G08B 17/00 - Fire alarmsAlarms responsive to explosion
G08B 19/00 - Alarms responsive to two or more different undesired or abnormal conditions, e.g. burglary and fire, abnormal temperature and abnormal rate of flow
A method of determining at least one point of entry of smoke into a smoke detection system, the system having a sampling pipe network including at least one sampling pipe and a plurality of sampling inlets through which an air sample can enter the at least one sampling pipe of the smoke detection system for analysis by a particle detector, said method including: determining a volume of sample air that has passed through at least part of the smoke detection system since a predetermined event or a value corresponding to said volume; and determining through which sampling inlet of the plurality of sampling inlets the smoke entered the smoke detection system based, at least in part, on the determined volume or value. Systems for implementing such a method and related methods are also described.
G01F 1/66 - Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
G08B 17/00 - Fire alarmsAlarms responsive to explosion
G01N 1/26 - Devices for withdrawing samples in the gaseous state with provision for intake from several spaces
G01N 35/08 - Automatic analysis not limited to methods or materials provided for in any single one of groups Handling materials therefor using a stream of discrete samples flowing along a tube system, e.g. flow injection analysis
G01N 1/00 - SamplingPreparing specimens for investigation
The invention relates to a particle detector, systems, and methods for detecting the presence of particles in a volume of air, most particularly it relates to detection systems and methods that use multiple modes of detection to detect the presence of particles. Preferably the particles being detected are particles that indicate an actual or incipient fire, or pyrolysis, such as smoke.
A sampling point for use with an aspirating particle detection system. The sampling point includes: a body; a plurality of apertures in the body for drawing an air sample from an ambient environment; an outlet for delivering the sampled air, at a predetermined sample flow rate, from the body into a sampling pipe of the network of sampling pipes; and a means for maintaining the predetermined sample flow rate regardless of the presence or absence of ambient flow of air about the body. A particle detection system, and air sampling system are also described.
A system and method of reducing the incidence of false alarms attributable to dust in smoke detection apparatus. The method includes obtaining at least two sample air flows, subjecting a first airflow to particle reduction and measuring the level of particles in the first airflow and generating a first signal indicative of the intensity. The method also includes measuring the level of particles in the second airflow and generating a second signal indicative of the intensity. The first signal is compared to a predetermined alarm level and, if the alarm level is achieved, the first and second signals are subsequently compared and an output signal is generated based on the relative difference between the first and second signals.
A surveillance system (10) for monitoring movement in a region of interest (18) is described. The surveillance system (10) includes: An image capturing system (12) having a field of view (16) including a region of interest (18), and adapted to capture an image of the region of interest (18). An image processing system (78) configured to process a time-sequential series of images of the field of view from the image capturing system such that at least a portion (52, 53, 54) of each processed image (50) is analysed for detecting movement within the region of interest (18). The image capturing system (12) is configured to capture, in each image, different apparent magnifications of respective zones (20, 22, 24) within the region of interest (18) in the field of view (16) that are at different distances from the image capturing system (12) such that an object (60) in at least one position in at least two of said zones has substantially the same apparent size in the images.
There is described a duct detector (1) and components (2, 3, 6) for duct detectors. In one form the duct detector (1) includes: a port unit (3) and detector unit (2). The port unit (3) is mountable to a duct in use so as to position one or more ports in the duct. The detector unit (2) includes a detection region. The port unit (3) and detector unit (2) are reconfigurable between a close coupled configuration and a separated configuration in which the units (2,3) are mountable with a variable separation between them and coupled by one or more elongate conduits (12A, 12B) to provide fluid communication between the units (2,3).
A sensing system and method for detecting particles in an air volume includes a main airflow path (A, F) including an inlet from the air volume. Also included is a collection site (E) within the main airflow path. The collection site is for drawing an air sample from the main airflow path. Additionally the system includes a means to induce a localised increase in particle speed at the collection site (E) relative to air speed along the remainder of the main airflow path. The means to induce a localised increase includes an auxiliary airflow path (K) from the main airflow path. The auxiliary airflow path (K) has an exit (I) upstream of the collection site. In an alternative form of the invention, the means to induce the localised increase in particle speed at the collection site comprises a venturi in the main airflow path with the collection site being disposed along the venturi.
There is describes a filter arrangement (10) for a particle detector (12) for detecting particles in an environment. The particle detector (12) can include one or more sensors (30) for analysing fluid in a detection region to produce sensor output. The filter arrangement (30) includes structure defining flow paths, for conveying fluid from the environment towards the detection region, including a first flow path (22), which includes a filter(26), and a second flow path (24) bypassing the filter(10). There is also provided a mechanism (120B) for controlling relative flow rates of fluid through the first flow path (22) and the second flow path (24) and a controller (32) configured to receive the sensor output corresponding to at least two relative flow rates and apply logic thereto to generate an output indicative of a condition of the filter.
A particle separation system for separating particles (B, F) in an airflow (A) upstream of a detection chamber in an aspirating smoke detector is disclosed. The particle separation system includes an airflow path (D) for directing the airflow from an inlet to an outlet. The airflow path (D) includes a first airflow path section (G) in a first direction and a second airflow path section (H) in a second direction, the first and second directions being different relative to each other. The airflow path also includes at least one electrically charged surface (C) such that the airflow (A) undergoes electrostatic precipitation as it traverses the airflow path (D). A method of separating particles in an airflow upstream of a detection chamber in an aspirating smoke detector is also disclosed.
B03C 3/00 - Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
B01D 53/32 - Separation of gases or vapoursRecovering vapours of volatile solvents from gasesChemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases or aerosols by electrical effects other than those provided for in group
G08B 17/10 - Actuation by presence of smoke or gases
A particle detector (10) including a chamber (12), a first aspirator (14), a sensor(s) (28), a controller (20) and clean air supply (18). The controller, when in a detecting mode, receives an indicative signal from the sensor and applies logic to the indicative signal to generate a further signal (22), and when in the purge mode controls substantial purging of the chamber of sample fluid with clean fluid from the clean fluid supply. The controller receives the indicative signal when the chamber is so purged and if necessary adjusts the logic in response thereto.
An apparatus and methods for detecting the presence of gases is described. The gas detection apparatus (10, 510) includes, a housing (30) adapted to be in fluid communication with a duct (504) of a particle detection system (500), and at least one gas detector (42, 43) sensitive to a target species arranged in fluid communication with the housing (30) to detect the presence of the target species in at least part of the air sample flowing in a duct (504). In one form the gas detection apparatus (10, 510) forms part of a system (700) for detecting a condition in an environment that includes, a particle detector (502); a duct system (504) in fluid communication with the environment and the particle detector (504) and an aspirator (518) to draw an air sample flow (72) from the environment to the particle detector (502).
A beam detector (10) including a light source (32), a receiver (34), and a target (36), acting in co-operation to detect particles in a monitored area (38). The target (36), reflects incident light (40), resulting in reflected light (32) being returned to receiver (34). The receiver (34) is a receiver is capable of recording and reporting light intensity at a plurality of points across its field of view. In the preferred form the detector (10) emits a first light beam (3614) in a first wavelength band; a second light beam (3618) in a second wavelength band; and a third light beam (3616) in a third wavelength band, wherein the first and second wavelengths bands are substantially equal and are different to the third wavelength band.
A method of detecting particles in an air flow is described. The method includes receiving a signal indicative of light intensity scattered from the air flow at a plurality of wavelengths and processing the signal indicative of the intensity of received light at each of the wavelengths and a corresponding wavelength dependent parameter to generate an output signal indicative of at least one characteristic of particles in the air flow. A particle detection system is also described.
A particle detection system 600 including; at least one light source (606) adapted to illuminate a volume being monitored (610) at at least two wavelengths; a receiver (604) having a field of view (620) and being adapted to receive light from at least one light source (606, 607) after said light has traversed the volume being monitored and being adapted to generate signals indicative of the intensity of light received at regions within the field of view of the receiver; a processor (624) associated with the receiver (604) adapted to process the signals generated by the receiver to correlate light received at at least two wavelengths in corresponding regions within the field of view of the receiver and generate an output indicative of the relative level of light received at the two wavelengths.
A particle detection system (100), such as an active video smoke detection system, includes at least one illumination means (102) for directing a beam (106) of radiation through at least part of the air volume being monitored (1 10), an image sensor (104) is positioned to capture images of at least part of a beam (106) from illumination means (102); and means to analyse (107) the captured images to detect the presence of particles within the volume. At least 29 different aspects are described for improving the sensitivity, usability, and robustness of particle detection. These include, for example, configuring illumination means (102) to create a curtain of light or a rapidly-scanned beam across the air volume (110), and configuring a reflector to steer or change direction of a beam reflected from illumination means (102).
An apparatus (10) for detecting particles in an airflow is disclosed. The apparatus can includes at least one light source (22, 24) for illuminating a one or more portions of the airflow, at least one photo-detector (30,32) positioned to detect light scattered from one or more illuminated volumes of the airflow. The least one light source (22, 24) and at least one photo detector (30,32)are arranged such that a signal indicative of light scattered from a plurality of illuminated volumes (38,34) can be derived from the output of the at least one photo detector (30,32). The apparatus also includes a signal processing apparatus configured to process said signals indicative of light scattered from a plurality of illuminated volumes to determine whether particles have been detected in the airflow.
An apparatus for detecting particles (100) is disclosed, including: at least one detection chamber (103) having means to detect particles in at least one region of interest (118) within the chamber; at least one inlet port (526) for introducing an air sample into a respective detection chamber; and at least one outlet (528) from the detection chamber; wherein the detection chamber (118) is configured such that the air sample enters the inlet port in a first direction and after traversing the region of interest flows towards the outlet at least partially in a direction other than the first direction.
A filter arrangement for removing impurities from a fluid is disclosed, the filter arrangement (10) includes a plurality of screen portions (18, 20) through which the fluid passes. The screen portions include a first screen portion (18) and a second screen portion (20) separated by a predetermined distance. The predetermined distance can be determined on the basis of a threshold particle length. In one form the filter arrangement (10) is mounted in a housing (16) which is configured to receive two filter elements (18, 20) arranged in a nested configuration. A particle detector using the filter is described.
B01D 29/56 - Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups Filtering elements therefor with multiple filtering elements, characterised by their mutual disposition in series connection
B01D 29/58 - Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups Filtering elements therefor with multiple filtering elements, characterised by their mutual disposition in series connection arranged concentrically or coaxially
B01D 46/00 - Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
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