CORRUGATED INSECT SCREEN

Description

[0001] The present disclosure relates to smoke detectors and, in particular, to a corrugated bug screen for smoke detector applications.

[0002] In photo-electric type smoke detectors, it is typically important to prevent insects from entering a smoke or detection chamber and creating a false signal. This is often done with a mesh screen that surrounds the air flow openings of the smoke or detection chamber. Conventional mesh bug screens are designed in such a way that they inhibit air flow behavior and in turn limit smoke entry (which may affect the ability of the smoke detector to accurately detect the presence of smoke).

[0003] Typically, the mesh bug screen is formed into a uniform, cylindrical shape to circumferentially surround a uniform, cylindrical air flow structure (e.g., a detection chamber) of a smoke detector.

[0004] EP 0569712 A1 discloses a photoelectric type fire detector comprising an optic base having a labyrinth, a bug screen provided on the outer periphery of the labyrinth of the optic base and a protective cover covering the optic base and the bug screen, the protective cover having a plurality of smoke inlet windows.

[0005] GB 2359354 A discloses a smoke detector with an insect screen formed from soft fibre having a mesh pattern and arranged so as to cover the entirety of a smoke detection section for preventing the intrusion of insects into the smoke detection space.

[0006] EP 1049059 A2 discloses a fire detector for sensing a fire, comprising an insect screen having a band-like metal thin plate, which prevents an insect from invading into the smoke chamber.

[0007] According to a first aspect, a detection chamber assembly of a smoke detector is provided. The detection chamber assembly includes upper and lower covers, louvers and a corrugated bug screen. The louvers are arranged with the upper and lower covers to define a chamber bound between the upper and lower covers and the louvers. The louvers include a first pair of louvers defining a first space therebetween to permit fluidic ingress to the chamber and a second pair of louvers defining a second space therebetween to permit fluidic ingress to the chamber. The second space is wider than the first space. The corrugated bug screen permits fluidic ingress to the chamber and inhibits bug ingress to the chamber. The corrugated bug screen is supported on the second pair of louvers at the second space.

[0008] The louvers may include multiple second pairs of louvers, each respectively defining second spaces therebetween, and each second space including one corrugated bug screen.

[0009] The mesh corrugation bug screen feature may be supported in slots defined in each of the second pair of louvers.

[0010] The corrugated bug screen may include a curved body.

[0011] The corrugated bug screen may permit fluidic ingress to the chamber in multiple directions normal to corresponding sections of the curved body.

[0012] The corrugated bug screen may include a row-columnar lattice structure.

[0013] The corrugated bug screen may extend inwardly toward the chamber.

[0014] The corrugated bug screen may extend outwardly from the chamber.

[0015] According to another aspect, a smoke detector is provided and includes a housing defining an interior in which a detection chamber assembly according to the first aspect is operably disposed. The corrugated bug screen is disposed at the second space.

[0016] The corrugated bug screen may extend inwardly toward the chamber.

[0017] The corrugated bug screen may extend outwardly from the chamber while remaining within the interior of the external structure.

[0018] Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed technical concept. For a better understanding of the disclosure with the advantages and the features, refer to the description and to the drawings.

[0019] Certain exemplary embodiments will now be described in greater detail by way of example only and with reference to the accompanying drawings in which: FIG. 1 is a perspective view of an exemplary detection chamber assembly for a photo-electric smoke detector; FIG. 2 is an exploded perspective view of a portion of the exemplary detection chamber of FIG. 1, illustrating an exemplary corrugated bug screen separated from an exemplary upper cover; FIG. 3 is an enlarged perspective view of a portion of the exemplary corrugated bug screen and a portion of the exemplary upper cover of FIG. 2; FIG. 4 is a top-down view illustrating the exemplary detection chamber assembly of FIG. 1 with an exemplary corrugated bug screen; FIG. 5 is an enlarged perspective view of a portion of the exemplary detection chamber assembly of FIG. 1 with two exemplary corrugated bug screens, each respectively disposed between a pair of louvers; FIG. 6 is a top-down view illustrating exemplary corrugated bug screens disposed between pairs of louvers; and FIG. 7 is a top-down view of a portion of an exemplary smoke detector with a portion of the housing removed to illustrate an exemplary location for the detection chamber assembly of FIG. 1.

[0020] As will be described below, a detection chamber assembly incorporating a corrugated bug screen and a smoke detector incorporating the detection chamber assembly are provided. The bug screen is formed into a corrugated shape with indentations and other geometric features designed to trap air and improve smoke entry. The corrugated shape can at least partially take the form of a star or be a mostly cylindrical shape with areas of corrugation that fit into or around open areas of an optical cover of the detection chamber assembly. It can also take the form of a partial mesh structure that covers large openings of the optical cover (e.g., where the corrugation may extend into the interior of the optical cover, between louvers).

[0021] With reference to FIGS. 1 and 2, a detection chamber assembly 101 is provided and includes an upper cover 110 (commonly referred to as an optical cover) and a lower cover 120. As shown, detection chamber assembly 101 or either the upper cover 110 itself or the lower cover 120 itself may include a plurality of louvers 130 (the louvers 130 may be attached to or formed together with the upper cover 110 or the lower cover 120). The upper and lower covers 110 and 120 can be, but are not required to be, annular or substantially circular. For purposes of clarity and brevity, the following description will relate to the cases in which the upper and lower covers 110 and 120 are substantially circular.

[0022] As shown in FIG. 2, the louvers 130 may be arranged circumferentially about the respective peripheries 111,121 of the upper cover 110 and the lower cover 120 to define a chamber 140 between the upper cover 110 and the lower cover 120 (bound circumferentially within the louvers 130). The louvers 130 may each be provided as static elements with somewhat complex geometries and include first pairs of louvers 131 and at least one or more second pair of louvers 132. It should be appreciated that each respective first pair of louvers 131 is separated from one another by a defined first space 1310, and each respective second pair of louvers 132 is separated from one another by a defined second space 1320. As will be described below, the second space 1320 is greater (i.e., wider than) the first space 1310. For purposes of clarity and brevity, the following description will relate to the cases in which the louvers 130 include multiple first pairs of louvers 131 and two pairs of second louvers 132, although it is envisioned that the detection chamber assembly 101 described herein may include any number of first pairs of louvers 131 and any number of second pairs of louvers 132.

[0023] As shown in FIG. 2, the multiple first pairs of louvers 131 are arranged to define multiple first spaces 1310 therebetween (i.e., one first space 1310 between each respective pair of first louvers 131). Each of the multiple first spaces 1310 may be configured and disposed to permit fluidic ingress to the chamber 140. The two pairs of second louvers 132 are arranged to define two second spaces 1320 therebetween (i.e., one second space 1320 between each respective pair of second louvers 132). Each of the second spaces 1320 is wider than any of the first spaces 1310 and may be configured and disposed to permit fluidic ingress to the chamber 140.

[0024] The detection chamber assembly 101 further includes at least one corrugated bug screen 150 (also 510, see FIG. 5). It will be appreciated that the corrugated bug screen 150, 501 described herein may be provided in multiple configurations. A first configuration of the corrugated bug screen 150 is shown in FIGS. 1-4, and a second configuration of the corrugated bug screen 510 is shown in FIGS. 5-6.

[0025] A first example of the corrugated bug screen 150, which is not part of the claimed invention, includes a body 151 that is disposed about the louvers 130 and a mesh corrugation feature 152. The mesh corrugation feature 152 can be provided as one, two or more than two mesh corrugation features 152. It is to be understood that the following description will relate to the cases in which two mesh corrugation features are provided in correspondence with the two second spaces 1320. Each mesh corrugation feature 152 may be coupled to the body 151 at a corresponding one of the two second spaces 1320 to permit fluidic ingress to the chamber 140 and to inhibit bug ingress to the chamber 140.

[0026] As shown in FIGS. 1-4, depicting the first configuration of the corrugated bug screen 150, the body 151 of the corrugated bug screen 150 may be substantially circular and configured to tightly fit about or around the louvers 130 (e.g., between the upper cover 110 and the lower cover 120). In these or other cases, the mesh corrugation features 152 can be respectively disposed in positional correspondence with each corresponding one of the second spaces 1320.

[0027] With continued reference to FIGS. 1 and 2 and with additional reference to FIG. 3, each of the mesh corrugation features 152 can include a tip 301 and first and second tapered sidewalls 302 and 303 extending in opposite directions from the tip 301 to the body 151. As shown in FIG. 3, the tip 301 and the corners between the body 151 and the first and second tapered sidewalls 302 and 303 can be curved in certain instances. In accordance with embodiments, each of the mesh corrugation features 152 permits fluidic ingress to the chamber 140 in a first direction D1 through the tip 301 and in second and third directions D2 and D3 through the first and second tapered sidewalls 302 and 303, respectively. In accordance with further embodiments, each of the mesh-corrugation features 152 can include a columnar lattice structure 310 at the tip 301 (i.e., a column of openings separated by a horizontal crossbar) and a row-columnar lattice structure 320 at the first and second tapered sidewalls 302 and 303 (i.e., rows and columns of openings separated by crisscrossing vertical and horizontal crossbars).

[0028] With reference to FIG. 4 and in accordance with alternative embodiments, each of the mesh corrugation features 152 can extend radially inwardly toward the chamber 140 or radially outwardly from the chamber 140.

[0029] With reference to FIG. 5, a detection chamber assembly 101 according to the invention is described. The detection chamber assembly 101 includes one or more of a second configuration of the corrugated bug screen 510 (i.e., between second louvers 132). The detection chamber assembly 101 illustrated in FIGS. 5 and 6 may be viewed as the same or similar to the detection chamber assembly 101 described above (e.g., the detection chamber assembly 101 includes one or more pair(s) of second louvers 132, etc.). The second configuration of the corrugated bug screen 510 (shown in FIGS. 5 and 6) may be supported at opposite ends thereof on each of the second pair of louvers 132 at each of the second spaces 1320. The second configuration of the corrugated bug screen 510 is designed to permit fluidic ingress to the chamber 140 and to inhibit bug ingress to the chamber 140.

[0030] As shown in FIG. 5, when referring to the second configuration of the corrugated bug screen 510, the opposite ends of the corrugated bug screen 510 can be supported in slots 511 defined in each of the second louvers 132. Also, as shown in FIG. 5, each corrugated bug screen 510 can include a curved body 512 and be designed to permit fluidic ingress to the chamber 140 in multiple directions D1-D5 normal to corresponding sections of the curved body 512. In accordance with further embodiments, each corrugated bug screen 510 can include a row-columnar lattice structure 520 (i.e., rows and columns of openings separated by crisscrossing vertical and horizontal crossbars) along the curved body 512.

[0031] With reference to FIG. 6 and in accordance with alternative embodiments, each corrugated bug screen 510 can extend radially inwardly toward the chamber 140 or radially outwardly from the chamber 140.

[0032] With reference to FIG. 7, a smoke detector 701 is provided, which includes a housing 710 defining an interior 711 and a detection chamber assembly 101, such as the detection chamber assembly 101 described above, which, as described above, includes a corrugated bug screen 150, 510. It should be appreciated that either of the configurations of the corrugated bug screen 150, 510 described above may be incorporated within the smoke detector 701 (although the corrugated bug screen is labeled 730 in FIG. 7).

[0033] As described above and shown in FIGS. 1-4, the corrugated bug screen 730 may include mesh corrugation features 731 (labeled 152 in FIGS. 1-4) at each of the second spaces to permit fluidic ingress to the chamber 140 and to inhibit bug ingress to the chamber 140. In the first configuration, which is not part of the invention, the corrugated bug screen 730 can include a body disposed about the louvers 130 with the mesh corrugation features 731 coupled to the body at the second spaces and either extending inwardly toward the chamber 140 or outwardly from the chamber 140 while remaining within the interior 711 of the housing 710. In a second configuration, which is according to the invention and which is described above and shown in FIGS. 5 and 6, the corrugated bug screen 730 (labeled 510 in FIGS. 5 and 6) is supported on the second pairs of louvers at the second spaces and can either extend inwardly toward the chamber 140 or outwardly from the chamber 140 while remaining within the interior 711 of the external structure 710.

[0034] Technical effects and benefits of the present disclosure are the provision of a smoke detector with improved smoke entry and an enhanced ability to detect conditions of various fires in a surrounding environment. Improved fluidic flows will allow for easier qualification testing at regulatory agencies and for easier requalification of production samples.

[0035] The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the technical concepts in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope of the invention as defined in the appended claims. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.

[0036] While the preferred embodiments to the invention have been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described.

Claims

1. A detection chamber assembly (101) of a smoke detector (701), the detection chamber assembly comprising: upper (110) and lower (120) covers; louvers (130) arranged with the upper (110) and lower (120) covers to define a chamber (140) bound between the upper (110) and lower (120) covers and the louvers (130), the louvers comprising: a first pair of louvers (131) defining a first space (1310) therebetween to permit fluidic ingress to the chamber (140), and a second pair of louvers (132) defining a second space (1320) therebetween to permit fluidic ingress to the chamber (140); and a corrugated bug screen (150; 152; 510) to permit fluidic ingress to the chamber (140) and to inhibit bug ingress to the chamber (140), characterized in that the second space (1320) is wider than the first space and in that the corrugated bug screen (150; 152; 510) is supported on the second pair of louvers (132) at the second space (1320).

2. The detection chamber assembly according to claim 1, wherein: the louvers (130) comprise multiple second pairs of louvers (132), each respectively defining second spaces (1320) therebetween, each second space comprising one corrugated bug screen (510).

3. The detection chamber assembly according to claim 1 or 2, wherein the corrugated bug screen (510) is supported in slots (511) defined in each of the second pair of louvers (132).

4. The detection chamber assembly according to claim 1, 2 or 3, wherein the corrugated bug screen (510) comprises a curved body (512).

5. The detection chamber assembly according to claim 3 or 4, wherein the corrugated bug screen (510) permits fluidic ingress to the chamber (140) in multiple directions normal to corresponding sections of the curved body (512).

6. The detection chamber assembly according to any one of claims 1 to 5, wherein the corrugated bug screen (510) comprises a row-columnar lattice structure (520).

7. The detection chamber assembly according to any of claims 1 to 6, wherein the corrugated bug screen (510) extends inwardly toward the chamber (140).

8. The detection chamber assembly according to any of claims 1 to 6, wherein the corrugated bug screen (510) extends outwardly from the chamber (140).

9. A smoke detector (701) comprising: a housing (710) defining an interior (711) in which a detection chamber assembly (101) according to claim 1 is operably disposed wherein the corrugated bug screen (150; 510) is disposed at the second space.

10. The smoke detector according to claim 9, wherein the corrugated bug screen (510) extends inwardly toward the chamber (140).

11. The smoke detector according to claim 9, wherein the corrugated bug screen (510) extends outwardly from the chamber (140) while remaining within the interior (711) of the external structure (710).