Patent Description:
In all environments, with the exception of a clean room, a sampling pipe network of an aspirated smoke detection system will experience accumulated particulate and contaminants, such as dust, in sampling holes of pipes in the network and inside of the pipes themselves. Such accumulated particulate and contaminants can restrict the flow of air within the pipes and eventually cause a low flow fault event in the aspirated smoke detection system.

Accordingly, it is known to activate a blowout device or a purge device in the sampling pipe network, for example, in harsh, dirty, or heavy particulate ridden environments, to perform a blowout action or a purge action that includes sending compressed air through one or more of the pipes in a direction that is opposite to the normal direction of airflow in the pipes. Such blowout devices or purge device performing such blowout actions or purge actions can effectively clear the pipes and any sampling holes therein of any accumulated particulate and contaminants. Indeed, purging the pipes of accumulated particulate and contaminants early and often can increase the effectiveness of the blowout device, the purge device, the blowout action, and the purge action because, over time, the accumulated particulate and contaminants can become attached to the pipes, most notably in humid environments, thereby making them more difficult to remove. Furthermore, purging the pipes of accumulated particulate and contaminants early and often can reduce or avoid low flow fault events.

However, problems can arise when the blowout device or the purge device is activated at regularly scheduled activation intervals, for example, daily, and performs the blowout action or the purge action when smoke is located in any of the pipes in the network. Indeed, if the blowout device or the purge device clears the pipes of any such smoke, the transport time of the smoke within the pipes can be delayed, and the aspirated smoke detection system can be delayed or inaccurate in detecting the smoke and transmitting signals indicative thereof.

In view of the above, there is a continuing, ongoing need for improved systems and methods.

<CIT> discloses a free blowing system for the automatic cleaning of fountain pipes of noise absorbing systems, characterized by the fact that in an enclosure a control unit, a functional light with a button, at least one suction control valve(s), pressure valve(s), a compressed air clutch and system heating are provided and form a building block that can be installed by muffing between the noise absorption system and the fountain pipes, with each sensor tube attached to a fountain tube connection connected to the free-blow system, which is connected, on the one hand, via a suction gas valve via the suction tube with the associated suction tube of the room intake system and, on the other hand, by a pressure valve with an internal pressure line, Which is fed via the compressed air clutch by an external factory compressor. Wherein the system is designed to generate a blowout delay when the smoke level within the sampling pipe is "too high" and no smoke alarms have been triggered. This is a specific delay designed to avoid clearing the pipe when smoke is present but is yet to be detected.

Document <CIT> discloses another example for a smoke detection system.

While this invention is susceptible of an embodiment in many different forms, there are shown in the drawings and will be described herein in detail specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention. It is not intended to limit the invention to the specific illustrated embodiments.

Embodiments disclosed herein include systems and methods for delaying or activating a blowout device or a purge device in a sampling pipe network of an aspirated smoke detection system. For example, in accordance with disclosed embodiments, systems and methods disclosed herein can include an isolation delay device that can prevent the blowout device or the purge device from activating and from performing a blowout action or a purge action while the aspirated smoke detection system is experiencing or detecting a triggering event or that can instruct the blowout device or the purge device to activate and perform the blowout action or the purge action responsive to the aspirated smoke detection system experiencing or detecting the triggering event. The isolation delay device disclosed herein can include a relay device, and the isolation delay device disclosed herein can be a programmable, air solenoid operated device. Furthermore, the blowout device or the purge device can be associated with a self-contained air source that the blowout device or the purge device can access to perform the blowout action or the purge action.

Systems and methods disclosed herein delay the blowout device or the purge device from activating and performing the blowout action or the purge action for a predetermined period of time. After expiration of the predetermined period of time, the blowout device is activated and performs the blowout action or the purge action immediately or in accordance with a regularly scheduled activation interval.

Systems and methods disclosed herein can delay the blowout device or the purge device from activating and performing the blowout action or the purge action until the aspirated smoke detection system no longer detects the triggering event at which time the blowout device or the purge device can be activated and perform the blowout action or the purge action immediately or in accordance with a regularly scheduled activation interval. The time until the aspirated smoke detection system no longer detects the triggering event can be an indefinite period of time.

When pipes in the sampling pipe network become dirty enough due to accumulate particulate and contaminants that have not been cleared via the blowout action or the purge action, for example, because the aspirated smoke detection system continues to detect the triggering event and because the blowout device or the purge device is not activated, the aspirated smoke detection system can detect a low flow fault event, for example, when the accumulated particulate causes airflow in the pipes to fall below a predetermined level.

<FIG> is a perspective view of a system <NUM> in accordance with disclosed embodiments. As seen in <FIG>, the system <NUM> can include a plurality of pipes <NUM> of a sampling pipe network coupled to an aspirated smoke detector <NUM>. A respective one of a plurality of blowout devices <NUM> can be coupled to each of the plurality of pipes <NUM> to perform the blowout action as disclosed herein. It is to be understood that the blowout devices <NUM> shown within the plurality of pipes <NUM> in <FIG> are exemplary only and that the location of the blowout devices <NUM> within the plurality of pipes is not a limitation of the embodiments disclosed herein. Instead, the blowout devices <NUM> could be located within the middle of or at either end of the plurality of pipes <NUM>.

<FIG> is a block diagram of one of the plurality of pipes <NUM>, the aspirated smoke detector <NUM>, and one of the plurality of blowout devices <NUM> of the system <NUM> of <FIG>. As seen in <FIG>, in normal operation, air can flow through the pipe <NUM> unobstructed in a first direction A. However, the blowout device <NUM> can be coupled to a delay device <NUM> and receive an activation signal or a delay signal from the aspirated smoke detector <NUM> or the delay device <NUM> with instructions for performing the blowout action that sends compressed air through the pipe <NUM> in a second direction B that is opposite the first direction A.

When the triggering event occurs, the aspirated smoke detector <NUM> can transmit a triggering event signal to the blowout device <NUM>, and, responsive thereto, the blowout device <NUM> can transmit a delay signal to the delay device <NUM> to prevent or delay the delay device <NUM> from transmitting the activation signal to the blowout device <NUM>. Additionally or alternatively, when the triggering event occurs, the aspirated smoke detector <NUM> can transmit the triggering event signal directly to the delay device <NUM>, and, responsive thereto, the delay device <NUM> can either abstain from or delay transmitting the activation signal to the blowout device <NUM> or can transmit a delay signal to the blowout device <NUM> instructing the blowout device <NUM> to delay activation. Additionally or alternatively, when the triggering event occurs, the aspirated smoke detector <NUM> can transmit the triggering event signal to the delay device <NUM>, and, responsive thereto, the delay device <NUM> can transmit the activation signal to the blowout device <NUM>. Additionally or alternatively, when the triggering event occurs, the aspirated smoke detector <NUM> can transmit the activation signal directly to the blowout device <NUM>.

The triggering event as disclosed herein can include a smoke event, an alert event, or an alarm event, for example, the aspirated smoke detector <NUM> detecting an increased smoke signal caused by obscuration in the pipe <NUM>. Responsive thereto, systems and methods can transmit the delay signal to the delay device <NUM> or the blowout device <NUM> or delay transmitting the activation signal to the blowout device <NUM> to delay the blowout action.

Alternatively, the triggering event as disclosed herein can include the aspirated smoke detector <NUM> detecting a predetermined level of particulate within the pipe <NUM> that indicates an environmental quality that warrants purging. Responsive thereto, systems and methods can transmit the activation signal to delay device <NUM> or the blowout device <NUM> to instruct the blowout device <NUM> to perform the blowout action.

Alternatively, the triggering event as disclosed herein can include the aspirated smoke detector <NUM> receiving a sensor signal from an endcap sensor associated with the pipe <NUM> that indicates pipe cleanliness that warrants purging. Responsive thereto, systems and methods can transmit the activation signal to delay device <NUM> or the blowout device <NUM> to instruct the blowout device <NUM> to perform the blowout action.

Alternatively, the triggering event as disclosed herein can include the aspirated smoke detector <NUM> detecting a predetermined level of air flow velocity or volumetric rate within the pipe <NUM> that indicates a decrease caused by pipe soiling that warrants purging. Responsive thereto, systems and methods disclosed herein can transmit the activation signal to the delay device <NUM> or the blowout device <NUM> to instruct the blowout device <NUM> to perform the blowout action. Systems and methods can measure the air flow velocity or the volumetric rate within the pipe <NUM> within a predetermined period of time after the blowout action, and if there is no improvement in the air flow velocity or the volumetric rate, then systems and methods disclosed herein can transmit a re-activation signal to the blowout device <NUM> to perform a re-blowout action with increased purge pressure.

Alternatively, the triggering event disclosed herein can include the aspirated smoke detector <NUM> receiving a foreign material signal indicative of a foreign material lodged within the pipe <NUM> or sampling holes therein. In these embodiments, when the triggering event occurs, the aspirated smoke detector <NUM> can transmit the triggering event signal and a dislodge signal to delay device <NUM> or the blowout device <NUM>, and, responsive thereto, the blowout device <NUM> can transmit high frequency air pulses through the pipe <NUM> in an attempt to dislodge the foreign material.

Alternatively, the triggering event disclosed herein can include a background signal of the aspirated smoke detector exceeding a predetermined level that warrants purging. Responsive thereto, systems and methods can transmit the activation signal to the delay device <NUM> or the blowout device <NUM> to instruct the blowout device <NUM> to perform the blowout action.

When the aspirated smoke detector <NUM> detects a smoke event immediately after or within a predetermined period of time after the blowout action, systems and methods disclosed herein can reduce any delays in activating the blowout device <NUM> or raise the level at which the aspirated smoke detector <NUM> detects the triggering event.

To compensate for the delay in the transport time of air within the pipe, systems and methods disclosed herein can temporarily increase the speed of a fan associated with the pipe <NUM> for a predetermined period of time after the blowout action or can temporarily raise the level at which the aspirated smoke detector <NUM> detects triggering event.

Systems and methods disclosed herein can create or access an event log in a database device that identifies when past triggering occurred.

Based on the event log, systems and methods disclosed herein can activate the blowout device <NUM> to perform the blowout action only at times when the triggering events are not historically common. For example, systems and methods disclosed herein can base a purge schedule for the blowout device <NUM> on the event log.

Systems and methods disclosed herein can create or access a flow rate log in a database device that identifies past flow rate values. Based on the flow rate log, systems and methods disclosed herein can identify a purge frequency for the blowout device <NUM> and increase the purge frequency when the flow rate log indicates improvement in flow rate values.

<FIG> is a block diagram of one of the plurality of pipes <NUM>, the aspirated smoke detector <NUM>, and one of the plurality of blowout devices <NUM> of the system <NUM> of <FIG> with an in-line filter <NUM> and a valve <NUM> in accordance with present invention. As seen in <FIG>, the in-line filter <NUM> is associated with the pipe <NUM> and located upstream of the blowout device <NUM> in the pipe <NUM>, and the valve <NUM> can provide an alternate path pipe for the compressed air that the blowout device <NUM> transmits in the second direction B during the blowout action. Without the valve <NUM>, the filter <NUM> could not otherwise be placed upstream of the blowout device <NUM> because the filter <NUM> would provide an obstruction to the compressed air flowing in the second direction B during the blowout action and, thus, would be damaged.

<FIG> is a block diagram of one of the plurality of pipes <NUM>, the aspirated smoke detector <NUM>, and one of the plurality of blowout devices <NUM> of the system <NUM> of <FIG> with a compressed air path pipe <NUM> from the blowout device <NUM> to the aspirated smoke detector <NUM> in accordance with disclosed embodiments. In addition to any of the embodiments disclosed herein, when the triggering event as disclosed herein occurs, for example, when the background signal of the aspirated smoke detector exceeds a predetermined level that warrants purging, the blowout device <NUM> can perform the blowout action in the compresses air path pipe <NUM> by transmitting high velocity compressed air to the aspirated smoke detector <NUM> via the compressed air path pipe <NUM> to clear the aspirated smoke detector <NUM> or specific areas thereof of accumulated particulate and contaminants.

It is to be understood that the blowout device <NUM> disclosed herein can be a source of compressed air fluidly coupled to the pipe <NUM> of the aspirating detector system <NUM> when activated to do so, such as via the activation signal from the aspirated smoke detector <NUM>. For example, the blowout device <NUM> can be activated via a pneumatic valve opening for a period of time to release the compressed air into the pipe <NUM>, thereby purging the pipe, such as of dust and dirt particles. Such a release can be termed a blowout action, which is a synonymous with a purge action.

Although examples have been described in detail above, other modifications are possible. For example, the logic flows described above do not require the particular order described or sequential order to achieve desirable results. Other steps may be provided, steps may be eliminated from the described flows, and other components may be added to or removed from the described systems. Other embodiments may be within the scope of the claims. The alternatives presented in this document may be combined, when not mutually exclusive.

Claim 1:
A system (<NUM>) comprising:
an aspirated smoke detector (<NUM>);
a sampling pipe (<NUM>) coupled to the aspirated smoke detector (<NUM>);
a blowout device (<NUM>) coupled to the sampling pipe (<NUM>); and
a delay device (<NUM>) coupled to the blowout device (<NUM>),
wherein, responsive to the aspirated smoke detector (<NUM>) detecting a triggering event, the aspirated smoke detector (<NUM>) transmits a triggering event signal to the blowout device (<NUM>),
wherein, responsive to the blowout device (<NUM>) receiving the triggering event signal, the blowout device (<NUM>) transmits a delay signal to the delay device (<NUM>), and
wherein, responsive to the delay device (<NUM>) receiving the delay signal, the delay device (<NUM>) delays the blowout device (<NUM>) from performing a blowout action in the sampling pipe by delaying transmission of an activation signal to the blowout device (<NUM>); and
an in-line filter (<NUM>) coupled to the sampling pipe (<NUM>) and located upstream of the blowout device (<NUM>) in the sampling pipe (<NUM>);
a valve (<NUM>) coupled to the blowout device (<NUM>); and
an alternate flow path pipe (<NUM>) coupled to the valve (<NUM>) and to the sampling pipe (<NUM>),
wherein the blowout action includes the blowout device (<NUM>) activating the valve (<NUM>) and sending compressed air to the sampling pipe (<NUM>) via the alternate flow path pipe (<NUM>) while avoiding the in-line filter (<NUM>).