Field Of Invention

The present invention relates to a fire extinguishing system with enhanced reliability. More specifically, the disclosed fire extinguishing system is capable of preventing spurious trigger attributed to sudden power surges or manually triggered due to ignorance or malicious intent. The invention will discern between fire and non-fire conditions and will only activate if the former occurs.

Background Of The Invention

With advancements in technology, automatic fire extinguishing systems have been widely deployed in various buildings or enclosed environment to control the spread of fire and ultimately to extinguish the fire. The major problem faced by all systems is accidental discharge or unintended discharge of the fire extinguishing system. Occurrence of false alarm not only wastes fire extinguishing resources but also causes disruption to commercial activities within the protected area. Additional loss may be incurred if there was damage to the equipment inflicted by the discharged fire extinguishing agent. Besides financial losses, diminished confidence towards integrity of the fire systems may lead to tragic consequences. Particularly, high prevalence of false alarm can significantly reduce alertness of the public towards fire incidents which may eventually cause loss of life and more. Further, some fire-extinguishing agents used in particular systems can have detrimental impact to the surrounding environment that unnecessary discharge is completely undesired. Erroneous activation can be attributed to faulty sensors, induced power surge, electrical disturbance, inherent system instabilities, human error or malicious intent. Error due to induced power surge and other electrical disturbances accounts for most cases of false triggering. In order to enhance or improve reliability of current automatic fire extinguishing system, better architectural design of the system is needed. Particularly, the system may contain a mechanism to verify signals generated in response to detection of fire occurrence and complete activation of the fire alarm is only permitted once the mechanism confirms the signal is valid. For example, China patent application no. 201076696 describes a fire alarm system with enhanced reliability. The described system has a temperature sensor used in conjunction with the smoke sensor to confirm fire occurrence. Another Chinese patent publication no. 201404622 addresses the problems of false fire alarm by simultaneously using smoke sensor, temperature sensor, air sensor and flame sensor to verify fire occurrence.

Summary Of The Invention

The present invention offers an automatic fire extinguishing system. Specifically, the disclosed system uses solid propellant for generation of fire extinguishing aerosol.

Another object of the disclosed invention is to provide fire extinguishing system with enhanced reliability to avoid erroneous activation of the system induced by abrupt electrical surge or other electrical disturbance.

Further object of the present invention is to provide a fail-safe fire extinguishing system equipped with verification mechanism to investigate validity of fire occurrence using two layers of fire detection module.

At least one of the preceding objects is met, in whole or in part, by the present invention, in which one of the embodiments of the present invention is a fire extinguishing system (100) installed in an enclosed environment comprising a control panel (105); a primary fire detecting module (110) for sensing fire occurrence in the enclosed environment connected to the control panel (105); and a plurality of fire extinguisher (130) positioned within the enclosed environment and each of the fire extinguishers (130) individually coupled with a timed firing module (121) that at least one of the timed firing modules connect to at least one of a plurality of secondary fire detecting modules (120) linked to the control panel (105); wherein the control panel (105) is configured to activate the secondary fire detecting modules (120) upon receiving a first signal generated by the primary fire detecting module (110) sensed the fire occurrence that at least one of the activated secondary fire detecting modules (120) prompts all the timed firing member to releases a second signal to the coupled fire extinguisher (130) to discharge fire extinguishing content once the secondary fire detecting module senses the fire occurrence. Further embodiment of the present invention includes a fire extinguishing system (100) installed in an enclosed environment comprising a control panel (105); a primary fire detecting module (110) for sensing fire occurrence in the enclosed environment connected to the control panel (105); and a plurality of fire extinguisher (130) positioned within the enclosed environment and each of the fire extinguishers (130) individually coupled with a timed firing module (121) that at least one of the timed firing modules connect to at least one of a plurality of secondary fire detecting modules (120) linked to the control panel (105); wherein the control panel (105) is configured to activate the secondary fire detecting modules (120) and prompt the timed firing module to release a second signal to the coupled fire extinguisher (130) to discharge fire extinguishing content upon receiving a first signal generated by the primary fire detecting module (110) sensed the fire occurrence that the second signal is permitted to arrive at the fire distinguisher once at least one of the activated secondary fire detecting modules (120) sense the fire occurrence or vice versa. In another embodiment, the disclosed system (100) includes as well an activating button (140) for a user to directly trigger the timed firing module (121) to release the second signal to the coupled fire extinguisher (130) to discharge fire extinguishing content. The activating button (140) facilitates the user to carry out earlier actions to against the fire prior to fully activation of the disclosed system.

Another embodiment of the disclosed system (100) my have the primary fire detecting module (110) to use two layers of sensors each measures a fire indicator and provides collective input as the first signal once the measured fire indicator exceeds a predetermined threshold.

In one embodiment, the primary (110) and secondary detecting modules (120) respectively measure different indicators for sensing fire occurrence that the indicator is smoke, temperature, or far infrared. Through measuring different indicators using two different modules, the signal regarding fire occurrence detected can be crosschecked prior to discharging the fire extinguishing content. In another embodiment, the primary fire detecting module (110) senses fire occurrence by detecting presence of smoke and/or measuring temperature of the enclosed environment against a predetermined threshold, while the secondary fire detecting module (120) senses fire occurrence by measuring intensity of far infrared emitted and/or ratio of an area emitting far infrared in a predefined area.

Brief Description Of The Drawings

Figure 1 is a block diagram showing one embodiment of the disclosed system;

and Figure 2 shows possible logic used in the disclosed system for signal verification.

Detailed Description Of The Invention

It is to be understood that the present invention may be embodied in other specific forms and is not limited to the sole embodiment described herein. However modification and equivalents of the disclosed concepts such as those which readily occur to one skilled in the art are intended to be included within the scope of the claims which are appended thereto. The present invention discloses a fire extinguishing system to be installed in an enclosed environment. The disclosed system is equipped with enhanced reliability which is fail-safe and capable of avoiding false alarms particularly caused by disturbance on the electrical grid powering the system. Essentially, the disclosed system comprises a control panel (105); a primary fire detecting module (110) for sensing fire occurrence in the enclosed environment connected to the control panel (105); and a plurality of fire extinguisher (130) positioned within the enclosed environment and each of the fire extinguishers (130) individually coupled with a timed firing module (121) that at least one of the timed firing modules connect to at least one of a plurality of secondary fire detecting modules (120) linked to the control panel (105); wherein the control panel (105) is configured to activate the secondary fire detecting modules (120) upon receiving a first signal generated by the primary fire detecting module (110) sensed the fire occurrence that at least one of the activated secondary fire detecting modules (120) prompts all the timed firing member to releases a second signal to the coupled fire extinguisher (130) to discharge fire extinguishing content once the secondary fire detecting module (120) senses the fire occurrence.

Preferably, the primary (110) and/or secondary fire detecting modules (120) described herein may include an integrated circuit with micro-controller, sensor, wired or wireless signal transmitting means and the like to facilitate performance of the disclosed system. Similarly, the control panel (105) is the central hub used to link most of the devices and sensors of the disclosed invention to form an operative system. Other components in the disclosed invention includes siren or alarm (107), emergency lighting and the like which connects to the control panel (105) as well and activated thereof in the incident of fire. Any modification made thereof shall not depart from the scope of the present invention.

It is important to be noted herein that the disclosed system uses fire detecting module of two different hierarchies to independently sense the fire occurrence. Particularly, the secondary fire detecting module (120) is put into a passive state, and only activated after receiving the first signal, to shield in from erroneous trigger induced by electrical disturbance. The secondary fire detecting module (120) is the gatekeeper of the disclosed system. More specifically, the first signal generated by the primary fire detecting module (110) requires verification from the secondary fire detecting module (120) in order to initiate the discharge of fire extinguishing content. Preferably, the disclosed system (100) demands at least one of the activated secondary fire detecting modules (120) acknowledge fire occurrence and prompt the timed firing modules (121) to send the second signal to at least one of the fire extinguisher (130) to discharge fire extinguishing content. In more specific, the secondary fire detecting modules (120) generates a second level decision input in the decision making matrix of the disclosed system (100) by enabling or disabling generation of the second signal corresponding to the first signal derived from various sensors used in the primary fire detecting module (110) to trigger the fire extinguisher (130). As long as the second signal is not enabled or generated, the disclosed system (100) masks the first signal to avoid spurious discharge of the fire extinguishing content. Figure 2 illustrates the possible logic used in one embodiment of the present invention to trigger the fire extinguisher. Generally, both the first and second signals are mathematically ANDED together to produce an output to permit discharge of the fire extinguishing content. Preferably, the disclosed fire extinguishing system (100) including the control panel (105), the primary fire detecting module (110), the secondary fire detecting module (120), the timed firing member (121) and the fire extinguishers (130) are powered by alternate current from the power grid.

To facilitate operation of the disclosed invention, the secondary fire detecting modules (120) are electrically linked to one another in a serial fashion with at least one of the secondary fire detecting module (120) connected to the timed firing modules (121) for transmission of the instruction to prompt the timed firing module (121) to release the second signal. In more detail, the secondary fire detecting modules (120) are linked to form a network to allow signal to be transferred from one unit to another. With even only one unit of the secondary fire detecting module (120) senses and qualifies an incident as fire occurrence, this information is spread through the network of secondary fire detecting modules (120) leading to subsequent transmission of instruction to the timed firing module (121). The linked secondary fire detecting modules may be arranged in a ring, line or bus topology to facilitate signal transmission. Likewise, the timed firing modules (121) form a linked network as well. Preferably, the timed firing modules are serially linked to one another with at least one of the timed firing modules connected to the secondary fire detecting modules (120). Therefore, the instruction received from the secondary fire detecting module (120) can be delivered to all the linked timed firing module (121) for generation of second signal thereof.

Pursuant to the preferred embodiment, the primary (110) and secondary detecting modules (120) respectively measure different indicators for sensing fire occurrence that the indicator can be smoke, temperature, or far infrared. These indicators are signs reflecting fire occurrence. Still, predetermined thresholds are assigned to sensors of each module to allow the module to generate corresponding signal accord to defined parameters. Only the measured volume of a given indicator exceeds the predetermined threshold or the reference value, the module shall recognize the indicator-providing incident as genuine fire and carry out corresponding actions thereof. More preferably, both primary fire detecting module (110) and secondary fire detecting module (120) of the disclosed system (100) are assigned to detect fire occurrence by measuring at least two different indicators. Specifically, the first and second signals are generated based on at least two different indicators measured. By measuring or sensing two different indicators, the disclosed system enhances reliability of the fire alarm as only presence of at least two indicators with measurable readings not lower than a reference can set the discharge of fire extinguishing content off. Moreover, the passive or inactive state of the secondary fire detecting module (120) in the present invention prior to activation shields the secondary fire detecting module (120) from being affected by the electrical disturbance which probably erroneously triggers generation of first signal from the primary fire detecting module (110). Thus, the secondary fire detecting module (120) functions as a gatekeeper to verify validity of the first signal through independently sensing or measuring fire occurrence before allowing the timed firing module (121) to release the second or discharging signal to the fire extinguisher (130). Preferably, the sensors used in the modules to perform the fire detection are wide area and long range detector capable of covering greater area within the enclosed environment. More preferably, the primary fire detecting module (1 10) senses fire occurrence by detecting presence of smoke and/or measuring temperature of the enclosed environment against a predetermined threshold, while the secondary fire detecting module (120) senses fire occurrence by measuring intensity of far infrared emitted and/or ratio of an area emitting far infrared in a predefined area. For example, the primary fire detecting module (110) may continuously measure temperature within the enclosed environment that the module is set off to generate the first signal once the measured temperature exceeds the predetermined threshold. Likewise, the sensor in the secondary fire detecting module (120) is activated to screen specific section in the enclosed environment at specific wavelength of infrared and measure a given area in the specific section emitting the infrared of specific range. If the area to section ratio or the area measured is higher than the threshold, the secondary fire detecting module (120) shall then validate occurrence of a genuine fire by generating the second signal to enable the first signal as well as trigger the fire extinguishers (130) to discharge.

It is important to be noted herein that the primary fire detecting module (110) in the present invention may employs multiple zones or layers fire detection for generation of the first signal. Specifically, the zone or layer refers to independent sensors capable of detecting fire occurrence and each zone can generate respective trigger signal to activate the fire extinguishing system to perform specific actions for preparing fire extinguishing process. In the embodiment which the primary fire detecting module (110) is a multi zones fire detecting module, the collective trigger signals generated from the all zones constitute the first signal to activate the second fire detecting module (120). Preferably, in one embodiment, the primary fire detecting module (110) is a two zones detection system. The zone can measure either similar or different fire indicators. Generally, the zone one sensor may measure heat or temperature within the enclosed environment while the zone two sensor detects smoke. Trigger signal of one of the zones may prompt the present invention to blare the siren in an intermittent fashion and/or switch on the emergency lighting device. Trigger signals received from both zones can cause continuous siren blaring, discontinuation of electricity supply or shielding of curtain/ damper besides serving as the first signal. In more specific, the primary fire detecting module has two layers of sensors each measures a fire indicator and provides collective input as the first signal once the measured fire indicator exceeds a predetermined threshold. Accordingly, the disclosed invention may be embodied in another form to attain similar outcome in verifying the first signal. Particularly, the fire extinguishing system (100) installed in an enclosed environment comprises a control panel (105); a primary fire detecting module (110) for sensing fire occurrence in the enclosed environment connected to the control panel (105); and a plurality of fire extinguisher (130) positioned within the enclosed environment and each of the fire extinguishers (130) individually coupled with a timed firing module (121) that at least one of the timed firing modules connect to at least one of a plurality of secondary fire detecting modules (120) linked to the control panel (105); wherein the control panel (105) is configured to activate the secondary fire detecting modules (120) and prompt the timed firing module to release a second signal to the coupled fire extinguisher (130) to discharge fire extinguishing content upon receiving a first signal generated by the primary fire detecting module (110) sensed the fire occurrence that the second signal is permitted to arrive at the fire distinguisher once at least one of the activated secondary fire detecting modules (120) sense the fire occurrence or vice versa. The first signal in such embodiment may simultaneously lead to activation of the secondary fire detecting module (120) and release of the second signal from the timed firing member. Yet, the second signal is prohibited to reach the fire extinguisher unless the secondary fire detecting module (120) senses the fire occurrence. Once verified fire occurrence, the secondary fire detecting module (120) route the second signal to the fire extinguisher (130) to trigger discharge of the fire extinguishing content. On the other hand, the disclosed invention disregards the first signal if the secondary fire detecting module (120) failed to acknowledge fire occurrence. An automatic mechanism may be incorporated thereof to default the system upon failure in recognizing fire occurrence at the secondary fire detecting module (120) over a predetermined period. Other embodiment may require the user to switch off the system for few seconds to reset the disclosed invention to default state.

Still, in one embodiment, the disclosed system further comprise an activating button (140) located inside or outside the enclosed area. The activating button (140) is capable of providing instruction to the timed firing module (121) to generate the second signal for the fire extinguishers (130) without the need of first signal and the instruction from the secondary fire detecting module (120). The activating button (140) allows the user to directly trigger the discharge bypassing the primary (110) and secondary fire detecting module (120). Specifically, the disclosed invention may further includes an activating button (140) for a user to directly trigger the timed firing module (121) to release the second signal to the coupled fire extinguisher (130) to discharge fire extinguishing content.

As in setting forth, each of the fire extinguishers (130) in the described system is individually coupled with a timed firing module (121) and a secondary fire detecting module (120) to verify the first signal. The disclosed system only activates the secondary fire detecting modules (120) upon generation of the first signal by the primary fire detecting module (110). The passive state ensures the secondary fire detecting modules (120) are less likely influenced by sudden power surges due to lighting, ground loop or other electrical disturbance. There is a slight delay in between generation of the first signal and the activation of the secondary fire detecting module (120) that the delay substantially shields the secondary fire detecting module (120) from being affected by the abrupt electrical surge. Preferably, the disclosed system positions the secondary fire detecting module (120) nearby the fire extinguisher (130) for sensing the fire occurrence. More preferably, the disclosed system has the primary (110) and Secondary fire detecting modules (120) installed at different locations in the enclosed environment. The disclosed system may have more than one primary fire detecting module (110) located in the enclosed environment to monitor greater area within the enclosed environment. Moreover, the fire extinguishers (130) in the disclosed system may adapt a sequential fashion with a predetermined delay in between discharges of two fire extinguishers (130). This feature avoids overload of the integrated circuit controlling the operation of the disclosed system (100) in the control panel (105) especially when the fire extinguishing content is aerosol-generating solid propellant requiring high temperature ignition. More specifically, the solid propellant requires to be electrically ignited to initiate the aerosol generation. Each electrical ignition draws a specific amount of current from the supplied power therefore simultaneous ignition of multiple solid propellant at the same time is likely to overload and burn the circuit. Apart from providing the second signal to trigger the discharge, the timed firing module (121) used in the present invention also controls timing of the discharge. The predetermined delay is Configured in the setting of the each timed firing module (121) that 2 to 5 second delay spared in between two sequential discharge. Through the specific delay in between discharge or ignition, overloading of the system (100) can be prevented. Relying on the circuit and the solid propellant used, the disclosed system in one embodiment may be able to ignite or initiate discharges of two or three fire extinguishers (130) concurrently as long there is no overloading of the circuit.

According to one embodiment, the disclosed system (100) may be configured to only discharge those fire extinguisher which the coupled secondary fire detecting module (120) senses and verifies fire occurrence as initially reported in the first signal. At least one of the fire extinguishers (130) discharge fire extinguishing content in such embodiment. Yet, it is most preferred that all the fire extinguishers (130) discharge its content even only one of the secondary fire detecting module (120) detects the fire occurrence to ensure optimal safety attained.

One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objects and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiment describes herein is not intended as limitations on the scope of the invention.