A system for fire detection and suppression

Abstract

A system including an air flow detector configured to draw air from an outlet to detect for smoke and to detect if the outlet is blocked; a thermal sensor configured to detect a temperature of air drawn by the air flow detector; a purge unit configured to purge the outlet in response to the air flow detector detecting a blockage at the outlet; and a deluge valve operable to allow fire suppression fluid to be provided to the outlet in response to the air flow detector detecting smoke and / or in response to the temperature detected by the thermal sensor is above a predetermined threshold.

Description

Field

[0001] The present invention relates to a system for fire detection and suppression. Preferred embodiments relate to a combined system for fire detection and deluge. Background

[0002] Existing fire sprinkler systems are prone to tampering and vandalism that affects the efficiency of the system to detect fires and the efficiency of the system to suppress fires. Summary of Invention

[0003] Preferred embodiments of the invention seek to address the disadvantage described above and / or to at least provide the public with a useful choice.

[0004] An aspect of the present invention provides a system including: an airflow detector configured to draw air from an outlet to detect for smoke and to detect if the outlet is blocked; a thermal sensor configured to detect a temperature of air drawn by the air flow detector; a purge unit configured to purge the outlet in response to the air flow detector detecting a blockage at the outlet; and a deluge valve operable to allow fire suppression fluid to be provided to the outlet in response to the air flow detector detecting smoke and / or in response to the temperature detected by the thermal sensor is above a predetermined threshold.

[0005] The system is for fire detection and suppression.

[0006] The system preferably includes a valve actuator arrangement. The valve actuator arrangement may be operable in one of a plurality of configurations that includes: a detection configuration in which the passage from the outlet to the air flow detector is open while the passage from the purge unit to the outlet is closed; and a purge configuration in which the passage from the purge unit to the outlet is open while the passage from the outlet to the air flow detector is closed.

[0007] In a preferred embodiment, the deluge valve is normally in a closed state and is operated to an open state in response to the air flow detector detecting smoke; and the purge unit is configured to purge the outlet after deluge valve changes from the open state to a closed state.

[0008] In response to a blockage being detected at the outlet, the purge unit may be configured to operate at least one purge cycle to clear the blockage from the outlet. Preferably, there is at least one purge cycle which includes at least two pulse cycles.

[0009] The system preferably further includes a control module that is configured to notify an operator if the air flow detector detects that the outlet is blocked. Preferably, the control module is configured to notify the operator if the outlet is blocked before initiating the at least one purge cycle. Preferably, the control module is configured to notify the operator if the outlet is still blocked after the at least one purge cycle.

[00010] Further features and / or aspects of the present invention will become apparent from the following detailed description. Brief Description of Drawings

[0010] Preferred embodiments of the invention will now be described, by way of non-limiting example, with reference to the accompanying drawing in which: Figure 1 shows a schematic view of the system according to an embodiment of the present invention. Description of Embodiments

[0011] Figure 1 shows a system 100 according to an embodiment of the present invention. The system is for detecting and suppressing fire. The system preferably includes a deluge system.

[0012] The system 100 has an outlet 190 from which air from a room is drawn into the system and from which a fire-suppressant is provided to the room. The fire-suppressant is preferably water. The room may, in a preferred embodiment, be a prison cell or a security room. The system includes one outlet per room. In other examples, the system may have two or more outlets per room. In a building that has a plurality of rooms, each room is provided with at least one outlet. Preferably, the operation of the outlet(s) in one room are independent of the operation of the outlet(s) in another room. The outlet 190 is preferably provided on a ceiling of the room. In other examples, the outlet 190 is provided on a side wall of the room. In yet other examples, the outlet is provided in a floor of the room.

[0013] A nozzle is located at the outlet 190. The nozzle has a dome-shape with a plurality of apertures distributed on the dome. Each aperture having a size of about 1 mm. The nozzle is preferably an anti-ligature nozzle. A person cannot vandalise the nozzle or pass a rope I cord through the nozzle that they can use to pull nozzle from the outlet or use to cause self-harm.

[0014] The system 100 is operable, by a control module, in a plurality of modes including a normal mode (to monitor the air drawn from the outlet), a purge mode (to clear any detected blockage at the outlet or in the pipe network), a deluge (or suppression) mode (to suppress a detected fire), and a drainage mode (to allow any fluid in the pipe network to be drained after the suppression mode). In some examples, the system may operate in the purge mode while also operating in the drainage mode. The normal mode is the default mode of operation of the system 100. As mentioned above, the operation of the outlet(s) in one room is independent of the operation of the outlet(s) in another room. For example, the outlet(s) in one room may be operated by the system 100 in a normal mode while outlet(s) of the system 100 in another room, e.g. an adjacent room, may be operating in a suppression mode. In a preferred embodiment, readings from one output may be informative of readings from another output. For example, if one output is blocked but smoke is detected from a nearby outlet may be indicative of a fire event.

[0015] The system 100 includes an air flow detector 110 configured to draw air from the outlet 190. The detector 110 is at least configured to detect for smoke and to detect if the outlet is blocked. The detector 110 is an aspirated smoke detector (ASD) that is configured to analyse smoke levels in the air drawn from the outlet. The detector 110 is configured to draw air from the outlet at a rate of between about 20 l / m and 40 l / m. In other examples, the detector is configured to draw air from the outlet at a rate of at least about 15l / m, at least about 20 l / m, or at least about 25 l / m.

[0016] The system 100 includes a thermal sensor. The thermal sensor is configured to detect a temperature of air drawn by the air flow detector 110. The thermal sensor is located within the outlet 190 located in the room. In particular, the system includes a pipe portion from an outlet with the thermal sensor fitted to the detector 110 and the thermal sensor. As the air flow detector 110 draws air from the outlet, a portion of the air passes towards the thermal sensor. The thermal sensor is a heat sensor. In other examples, the thermal sensor is in proximity to the outlet.

[0017] In the normal mode of operation, the detector 110 draws air from the outlet 190. Based on the air drawn from the outlet 190, the system 100 determines a presence of smoke particles in the drawn air, determines a temperature (which may include a change in temperature) of the drawn air, and determines if an air flow rate drops below a nominal value that is indicative of a blockage in the outlet and / or a blockage in the pipe network.

[0018] The system 100 includes a purge unit 130 configured to purge the outlet 190 in response to the air flow detector 110 detecting a blockage at the outlet 190 or a blockage in the pipe network. The blockage could affect the detection capabilities by the detector 110 and the sensor during the normal mode. The purge unit 130 includes an air compressor that is configured to provide compressed air towards the outlet 190. The system 100 initiates the purge sequence by energising a solenoid 134 for a period of time to allow for any obstructions to be removed. The compressed air can be provided in one or more pulses. The or each pulse may be one second or a few seconds long.

[0019] In response to a blockage being detected at the outlet 190 or in the pipe network during the normal mode, the system assumes the purge mode to self-clean and remove or dislodge the blockage. In this purge mode, the purge unit 130 is configured to operate at least one purge cycle to clear the blockage from the outlet 190. Preferably, the at least one purge cycle includes at least two pulse cycles. In other examples, the at least one purge cycle is one cycle, two cycles, three cycles or more than four cycles. One cycle may have one or more pulses of compressed air.

[0020] In the purge mode, air flow to the detector 110 as well as the deluge and drain actuators are also closed off. In some examples, after a completion of a suppression mode, the system may operate in the purge mode and drain mode simultaneously.

[0021] The purge unit then runs a first cycle by energizing the solenoid 134. Once the first cycle is complete, the system 100 returns to the normal mode. If the system determines, after the first cycle is complete, that a blockage is still detected, the system 100 will enter into the purge mode and repeat the purge cycle at least two additional cycles. If the blockage is still detected after the additional cycles, the system notifies an operator for further investigation.

[0022] The system 100 includes a deluge valve 152 operable to allow fire suppression fluid to be provided to the outlet 190. The valve 152 is actuated in response to the air flow detector 110 detecting smoke and / or in response to the temperature detected by the thermal sensor is above a predetermined threshold. The deluge valve 152 is normally in a closed state and is operated to an open state in response to the air flow detector detecting smoke. The system 100 is in the suppression mode when the deluge valve 152 is in the open state.

[0023] The system 100 maintains the suppression mode for an operating period of time. The operating period may be determined by the system 100 in response to the air flow detector 110 and / or the thermal sensor. For example, the operating period may be higher if there is a high count of smoke particles in the air drawn from the outlet 190 or if the thermal sensor detects a high temperature of the air drawn from the outlet 190. Alternatively, the operating period may be a nominal period. For example, the operating period may be at least about 5 minutes. The system assumes the purge mode after the suppression state. In this regard, the purge unit 130 is configured to purge the outlet after deluge valve changes from the open state to a closed state.

[0024] The fire suppression system 100 includes a valve actuator arrangement. The valve actuator arrangement may be operable in one of a plurality of configurations that includes: a detection configuration in which the passage from the outlet to the air flow detector is open while the passage from the purge unit to the outlet is closed; and a purge configuration in which the passage from the purge unit to the outlet is open while the passage from the outlet to the air flow detector is closed.

[0025] The valve actuator arrangement includes a plurality of actuators. The actuators are electrically operated by a control module of the system. The plurality of actuators includes: • a detector (first) actuator 112 located between the air flow detector 110 and the outlet 190; • a purge (second) valve 132 and a purge actuator 134 located between the purge unit 130 and the outlet 190; • a drain (third) actuator 142 located between a drain 140 and the outlet 190; • a deluge (fourth) actuator 152 located between a fire suppressant reservoir (e.g. a water tank) and the outlet 190;.

[0026] Each of the actuators has an open state and a closed state depending on the mode of operation of the system. When one of the actuators is in the open state, the other actuators are in the closed state.

[0027] The fire suppression system 100 further includes a control module. The control module includes one or more computer processors that are configured to execute computer-executable instructions, stored on a computer-readable medium, to perform one or more of the operations described above. The control module is configured to cause the system 100 to operate in one of the modes described above. The control module is configured to notify an operator if the air flow detector detects that the outlet is blocked after the completion of at least one purge cycle. The control module is configured to cause the actuators described above to assume an open state or closed state.

[0028] The various embodiments of the present invention described above have been presented by way of example only, and not by way of limitation. It will be apparent to a person skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. The present invention should not be limited by any of the exemplary embodiments described above.

Claims

1. A system for detecting and suppressing fire, the system including:an air flow detector configured to draw air from an outlet to detect for smoke and to detect if the outlet is blocked;a thermal sensor configured to detect a temperature of air drawn by the air flow detector;a purge unit configured to purge the outlet in response to the air flow detector detectinga blockage at the outlet; anda deluge valve operable to allow fire suppression fluid to be provided to the outlet in response to the air flow detector detecting smoke and / or in response to the temperature detected by the thermal sensor is above a predetermined threshold.

2. The system of claim 1, further including a valve actuator arrangement that is operable in one of a plurality of configurations that includes:a detection configuration in which the passage from the outlet to the air flow detector is open while the passage from the purge unit to the outlet is closed; anda purge configuration in which the passage from the purge unit to the outlet is open while the passage from the outlet to the air flow detector is closed.

3. The system of claim 1 or 2, wherein:the deluge valve is normally in a closed state and is operated to an open state in response to the air flow detector detecting smoke; andthe purge unit is configured to purge the outlet after deluge valve changes from the open state to a closed state.

4. The system of any one of claims 1 to 3, wherein, in response to a blockage being detected at the outlet, the purge unit is configured to operate at least one purge cycle to clear the blockage from the outlet.

5. The system of claim 4, wherein the at least one purge cycle includes at least two pulse cycles.

6. The system of claim 4 or 5, wherein the system includes a control module that is configured to notify an operator if the air flow detector detects that the outlet is blocked after the at least one purge cycle.

7. The system of any one of claims 1 to 6, wherein a nozzle is located at the outlet, the nozzle having a dome-shape with a plurality of apertures each aperture having a size of about 1 mm.

8. A prison cell including the system of any one of claims 1 to 7.

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