Point detector for fire alarm system

Abstract

A point detector (1) for a fire alarm system. The point detector (1) includes a fan (2) configured to aspirate air from a surrounding environment; and an inlet (3) in flow communication with the fan (2); the inlet (3) is configured to split the incoming flow into multiple streams (4); and each stream (4) of the multiple streams (4) is configured to be in flow communication with a respective sensing device (6).

Claims

1. A point detector (1) for a fire alarm system, the point detector (1) comprising: a fan (2) configured to aspirate air from a surrounding environment; an inlet (3) in flow communication with the fan (2); and a smoke detector (6a), a heat detector (6b) and a carbon monoxide detector (6c); wherein the inlet (3) is configured to split the incoming flow into multiple streams (4); wherein the smoke detector (6a) is for sensing smoke in a first stream (4a) of the multiple streams (4); wherein the heat detector (6b) is for sensing heat in a second stream (4b) of the multiple streams (4); wherein the carbon monoxide detector (6c) is for sensing carbon monoxide in a third stream (4c) of the multiple streams (4); and wherein the point detector (1) is configured to generate an alarm when at least two of smoke, heat, and carbon monoxide are detected by the smoke detector (6a), the heat detector (6b), and the carbon monoxide detector (6c), respectively.

2. A point detector (1) as claimed in claim 1, comprising an early-warning smoke detector (5).

3. A point detector (1) as claimed in claim 2, wherein the early-warning smoke detector (5) is configured to be more sensitive to smoke than the smoke detector (6a).

4. A point detector (1) as claimed in claim 2, wherein the point detector (1) is configured to use the fan (2) to aspirate air from a surrounding environment in response to the early-warning smoke detector (5) detecting smoke.

5. A point detector (1) as claimed in claim 2, wherein the point detector (1) is configured to increase the speed of the fan (2) in response to the early-warning smoke detector (5) detecting smoke.

6. A point detector (1) as claimed in claim 2, comprising a controller configured to control the speed of the fan (2) in response to the early-warning smoke detector (5) detecting smoke.

7. A point detector (1) as claimed in claim 1, wherein the point detector (1) is configured to simultaneously operate at least two of the smoke detector (6a), the heat detector (6b), and the carbon monoxide detector (6c).

8. A point detector (1) as claimed in claim 1, comprising a processor; wherein the processor is configured to control the operational function of the point detector (1).

9. A method of operating a point detector (1) including a fan (2) configured to aspirate air from a surrounding environment; an inlet (3) in flow communication with the fan (2); and a smoke detector (6a), a heat detector (6b) and a carbon monoxide detector (6c), the method comprising: aspirating air from a surrounding environment using the fan (2); splitting an incoming flow at the inlet (3) into multiple streams (4), wherein the inlet (3) is in flow communication with the fan (2); using the smoke detector (6a) for sensing smoke in a first stream (4a) of the multiple streams (4); using the heat detector (6b) for sensing heat in a second stream (4b) of the multiple streams (4); using the carbon monoxide detector (6c) for sensing carbon monoxide in a third stream (4c) of the multiple streams (4); determining, using each of the smoke detector (6a), the heat detector (6b), and the carbon monoxide detector (6c) in flow communication with the first stream (4a), the second stream (4b) and the third stream (4c) respectively, a property of the flow; and generating an alarm when at least two of smoke, heat, and carbon monoxide are detected by the smoke detector (6a), the heat detector (6b), and the carbon monoxide detector (6c) respectively.

10. A method as claimed in claim 9, comprising: detecting smoke using an early-warning smoke detector (5).

11. A method as claimed in claim 10, comprising: aspirating air from the surrounding environment using the fan (2) in response to the early-warning smoke detector (5) detecting smoke.

12. A method as claimed in claim 10, wherein the early-warning smoke detector (5) is configured to be more sensitive to smoke than the smoke detector (6a).

13. A method as claimed in claim 11, comprising: increasing a speed of the fan (2) in response to the early-warning smoke detector (5) detecting smoke.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Certain example embodiments of the invention will now be described by way of example only and with reference to the accompanying drawings in which:

(2) FIG. 1 shows a schematic diagram of a point detector using a fan; and

(3) FIG. 2 shows a schematic diagram of another point detector using a fan.

DETAILED DESCRIPTION OF THE INVENTION

(4) With reference to FIG. 1 and FIG. 2, a point detector 1 comprises a fan 2, an inlet 3, multiple streams and/or multiple flow paths 4, an early-warning smoke detector 5 and sensing devices 6.

(5) The fan 2 is configured to aspirate air from a surrounding environment of the point detector 1. As such, a sample of air may be actively drawn from the surrounding environment to the point detector 1 using the fan 2. The fan may be any conventional fan, pump or blower as are readily known and understood in the art.

(6) The aspirated air from the fan 2 is directed to the inlet 3 via a flow path. As such the fan 2 is in flow communication with the inlet 3. The inlet 3 splits the incoming flow into multiple streams 4. To split the incoming stream the inlet 3 may be a four-way valve, the inlet 3 comprising one inlet port and three outlet ports. Whilst three streams 4 are shown in the Figures, the inlet 3 may split the incoming flow into an appropriate number of streams 4 as required.

(7) In flow communication exclusively with a stream 4 of the multiple streams 4 is the sensing device 6. The sensing device 6 is for determining and/or detecting a condition and/or substance indicative of a fire. Sensing devices 6 which may be used for determining and/or detecting a condition and/or substance indicative of a fire are well-known in the art and therefore will not be described in any detail herein.

(8) The point detector 1 as shown in the Figures may comprise an early-warning smoke detector 5. The early-warning smoke detector 5 is preferably more sensitive to smoke than any other sensing device 6 in the point detector 1 and thus under passive detecting conditions, wherein air flows to the point detector 1 via stochastic processes rather than being aspirated, the early-warning smoke detector 5 may determine a presence of smoke in the surrounding environment before any other sensing devices 6 in the point detector 1. As such the early-warning smoke detector 5 need not be in flow communication with the fan 2, as shown in FIG. 1, but it may be in flow communication with the fan 2 nevertheless, as shown in FIG. 2.

(9) The point detector 1 may be configured such that air is only aspirated via the fan 2 once smoke has been detected, or its presence determined, using the early-warning smoke detector 5. Once the early-warning smoke detector 5 detects smoke, the point detector 2 may therefore be configured to increase a speed of the fan, such that air is aspirated to the inlet 3 and thus actively passed to the sensing devices 6. The speed and/or operation of the fan 2 may be controlled via a controller (not shown).

(10) The speed of the fan 2 may either be increased from a zero-value (i.e. it is switched on), and/or may be increased such that the fan 2 transitions from a low-power mode to a high-power mode. Whilst the fan may operate in a low-power mode at all times in the point detector 1 shown in both FIG. 1 and FIG. 2, it will be appreciated that operating the fan 2 in a low-power mode in the point detector of FIG. 2 will provide active detecting conditions for the early-warning smoke detector 5.

(11) The aspirated air is provided to the inlet 3, which splits the incoming flow into multiple streams 4. In each stream 4 is a respective sensing device 6. As such the sensing device 6 may be a smoke detector 6a in flow communication with a first stream 4a, a heat detector 6b in flow communication with a second stream 4b, or a carbon monoxide detector 6c in communication with a third stream 4c. Whilst the point detector 1 shown in the Figures comprises three sensing devices 6, it is to be appreciated that the point detector 1 may only require at least two of the sensing devices 6 as appropriate.

(12) The point detector 1 may generate an alarm when at least two of the smoke detector 6a, the heat detector 6b, and the carbon monoxide detector 6c detects smoke, heat, and carbon monoxide, respectively. The combinations of signals from the sensing devices 6a, 6b, 6c may be used by the point detector 1 to differentiate and/or distinguish between different fire sources and/or conditions and thus an appropriate alarm may be generated.

(13) The point detector 1 may be a standalone device comprising a power source (not shown), such as a battery. Similarly it may be connected to an external power source (not shown).

(14) The point detector 1 may comprise a processor (not shown). The processor may be configured to operate the controller for the fan 2. The processor may be configured to receive signals from the sensing devices 6 when they sense and/or detect a substance and/or condition they are configured to sense and/or detect. The processor may be configured to generate the alarm upon receiving the signals from the sensing devices 6. The processor may be configured to monitor a battery life of the point detector if it is a battery powered device. The processor may be configured to emit a signal to an external monitoring system, notifying it of an alarm event. As such the point detector may comprise communication means (not shown), such as a wired electrical communication or a wireless communication device configured to receive and/or emit Bluetooth, infrared, of Wi-Fi signals, or any other suitable method of external communication, as appropriate.