Patent Application
20230225307
The present disclosure relates generally to insect guards for use in devices and systems for aspirated smoke, gas, or air quality monitoring.
Some smoke detection systems have a number of sample points spaced around a building that are connected via sampling tubes to a remotely located single central detector apparatus that samples air taken from the sample points to determine if smoke, harmful chemicals, or a fire is present in an area of the building. For example, such systems may be referred to as very early smoke detection apparatus (VESDA) systems.
In some jurisdictions, it is a requirement of fire standards that smoke detection systems be fitted with an insect guard in which a mesh is used to prevent entry of large insects which may trigger a false alarm if the insect reaches the smoke detection chamber. In such implementations, the insect guard aperture size is specified by the applicable fire standards.
Although used for this purpose, meshes readily accumulate dust, lint, and other particulate and, therefore, impede the entry of smoke and other harmful particles into the detection unit. This is especially true of meshes placed in the air flow path of aspirated smoke detection systems, which is almost always where they will be placed to keep insects out of the unit.
Devices, methods, and systems having insect guards in devices and systems for aspirated smoke, gas, or air quality monitoring are described herein. One aspirated smoke, gas, or air quality monitoring unit includes a detector module that includes at least one particulate sensing chamber within the detector module and an air inlet connecting the sampling tube to the particulate sensing chamber allowing communication of air from the sampling tube to the particulate sensing chamber; and a spiral shaped insect guard positioned within the inlet. Embodiments of the present disclosure use tubes to sample air, smoke, and/or gas from locations in a building that are remotely located from a central detector module (air quality monitoring unit).
An insect guard structure is proposed in the present disclosure that uses a wire element formed into a spiral form, by coiling it within a plane such that the wire coils around itself creating a larger coil in each revolution around a reference point at the center of the spiral. In the embodiments of the present disclosure, the gap between adjacent outside surfaces of two adjacent coils is no more than that permitted by an applicable government standard, such as UL Standard 268, 7th edition. Section 7.2.
An alternate form is the wire element formed in a zig-zag pattern where the gap between adjacent layers is no more than the permitted standard.
The advantage of these structures is that the relative aperture area compared to the overall area is high, compared with mesh, allowing less impedance to air flow and, therefore, less accumulation of airborne dust.
The types of wire used to create the spiral can be of different cross sections and can offer different characteristics of air flow rate, turbulence generation, and/or dust accumulation, among other characteristics. For example, the wire can be a circular, ellipsoidal, or tear drop shape. Cross sectional shapes can also be polygons, such as triangles, rectangles, rhombuses, other parallelograms, trapeziums, trapezoids, and the like.
In one implementation, a rectangular cross section wire element version used in aspirated systems, can have its windward edge tapered, creating a trapezium shape in order to reduce the windward edge surface and to reduce aerodynamic resistance and turbulence further reducing the propensity to collect dust from the air flow. This design is desirable as creation of the shape is relatively easy from a manufacturing standpoint as the wire can be tapered before the coiling process to create the spiral is implemented. A similar functional effect can also be accomplished with ellipsoidal cross section and tear drop cross section wire elements as will be discussed in more detail below with respect to
This insect guard is a product differentiator for air detection systems as it meets regulatory requirements while reducing or minimizing resistance to air flow or air movement and reducing the likelihood of blockage due to contamination of the guard. A spiral insect guard, which may be made of plastic, metal, or other solid material, is placed in such a way that air containing smoke must pass through it before entering the region where smoke may be detected. The distance of the spacing between the turns of the spiral is set so that insects are prevented from entering the smoke detection area and potentially triggering a false alarm.
In the following detailed description, reference is made to the accompanying drawings that form a part hereof. The drawings show by way of illustration how one or more embodiments of the disclosure may be practiced.
These embodiments are described in sufficient detail to enable those of ordinary skill in the art to practice one or more embodiments of this disclosure. It is to be understood that other embodiments may be utilized and that mechanical, electrical, and/or process changes may be made without departing from the scope of the present disclosure.
As will be appreciated, elements shown in the various embodiments herein can be added, exchanged, combined, and/or eliminated so as to provide a number of additional embodiments of the present disclosure. The proportion and the relative scale of the elements provided in the figures are intended to illustrate the embodiments of the present disclosure and should not be taken in a limiting sense.
The figures herein follow a numbering convention in which the first digit or digits correspond to the drawing figure number and the remaining digits identify an element or component in the drawing.
As used herein, “a”, “an”, or “a number of” something can refer to one or more such things, while “a plurality of” something can refer to more than one such things. For example, “a number of components” can refer to one or more components, while “a plurality of components” can refer to more than one component.
This can be beneficial as individual modules can be selectively removed for maintenance or repair without having to disconnect the sampling tubes. Similarly, the insect guard can be removed and cleaned or replaced.
As shown in
The cable conduit 112 connects to a cable management module 108 portion of the base 102. The cable management module 108 has a housing with a cover to keep connections for power and data communication to and from the device out of sight and secure from tampering. The cable conduit also provides those functions. In the embodiment of
In the embodiment of
In some embodiments, the covers of one or more modules of the aspirated smoke, gas, or air quality monitoring system device can be secured such that they need to be removed by a tool (specialized tool carried by a technician). In this manner, it is likely that those wishing to tamper with the aspirated smoke, gas, or air quality monitoring system device will not be able to access the internal components of the modules.
On the right side of the aspirated smoke, gas, or air quality monitoring system device illustrated in
In the embodiment illustrated in
A sampling point 222 is connected at the other end of the sampling tube 214. The sampling point collects air from an area being monitored and a pump pulls the air through the sampling point 222 into the sampling tube 214, through the tube and into the sensing unit 202, where the air is tested for particulate, chemicals or other items that may be harmful to occupants or indicate an emergency condition (fire) in the monitored area.
A spiral shaped insect guard (440 in
The monitoring system can be configured to be located within a building and as shown in
As shown in
In some embodiments, each detector module can also have a filter that can be removed from the detector module without disassembling the detector module. Such functionality can thereby save the technician's time during maintenance of the system.
In use, the module 404 is connected, via inlets 424 and outlets 434 to corresponding inlet and outlet ports of the base 302 of
As can be understood from the layout of the module shown, in the embodiment of
Each air sampling path draws air in from one of the tubes 314 and tests the air to see if it contains smoke, undesired chemicals, or a threshold level of particulate (by using a sensor in the particulate sensing chamber designed to identify one or more such particles). Additionally, the sensors can be easily changed to repurpose a unit to sense a different type of particle which can be beneficial in some implementations.
In the embodiment illustrated in
The implementation of
The spiral of the spiral insect guard 440 is comprised of a number of coils of wire that are coiled around a central reference point forming the center of the spiral. The spacing between these wire coils can be any suitable distance. For example, the spacing distance can be determined based on an applicable government standard. For instance, in one example embodiment, the spiral of the spiral insect guard 440 is comprised of a single wire that is coiled in a number of coils of wire and wherein a maximum opening size between adjacent outside surfaces of two adjacent coils is not greater than 1.27 mm.
Another easy to manufacture design is shown in
Other quadrilateral shapes can be used. For example, in
Such aerodynamic effects can also be provided by the designs shown in
The embodiments of the present disclosure provide greater flexibility in creating an aspirated smoke, gas, or air quality monitoring system that includes an insect guard that provides more air flow and allows the insect guard to be independently cleanable and/or replaceable.
It is to be understood that the above description has been made in an illustrative fashion, and not a restrictive one. Combination of the above embodiments, and other embodiments not specifically described herein will be apparent to those of skill in the art upon reviewing the above description.
The scope of the various embodiments of the disclosure includes any other applications in which the above structures and methods are used. Therefore, the scope of various embodiments of the disclosure should be determined with reference to the appended claims, along with the full range of equivalents to which such claims are entitled.
In the foregoing Detailed Description, various features are grouped together in example embodiments illustrated in the figures for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the embodiments of the disclosure require more features than are expressly recited in each claim.
Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.
This Application claims priority to U.S. Provisional Application No. 63/300,161, filed Jan. 17, 2022, the contents of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 63300161 | Jan 2022 | US |
