U.S. patent application number 15/936073 was filed with the patent office on 2019-09-26 for protective cover for chamberless point sensor.
The applicant listed for this patent is Kidde Technologies, Inc.. Invention is credited to Jennifer M. Alexander, Kenneth Bell, Michael J. Birnkrant, Peter R. Harris, David L. Lincoln.
Application Number | 20190293556 15/936073 |
Document ID | / |
Family ID | 65911063 |
Filed Date | 2019-09-26 |
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United States Patent
Application |
20190293556 |
Kind Code |
A1 |
Lincoln; David L. ; et
al. |
September 26, 2019 |
PROTECTIVE COVER FOR CHAMBERLESS POINT SENSOR
Abstract
A covered chamberless particulate detector includes a
chamberless detector configured to produce a signal when
particulate sensing events occurs, one or more optical emitters
configured to emit one or more emitting cones of light, one or more
optical sensors defining one or more receiving cones and configured
to detect occurrence of particulate sensing events, and a
protective cover defining an inside region and an outside region.
Each of the one or more emitting cones of light is configured to
overlap with each of the one or more receiving cones, thereby
creating one or more sensing volumes which may be in the inside
region, the outside region, or both regions. The protective cover
can be transparent, partially transparent, or opaque, and can
include apertures. The optical emitters and detectors can use one
or more wavelengths, allowing discrimination of various airborne
particulates.
Inventors: |
Lincoln; David L.;
(Johnston, RI) ; Birnkrant; Michael J.;
(Wethersfield, CT) ; Bell; Kenneth; (Epsom,
GB) ; Harris; Peter R.; (West Hartford, CT) ;
Alexander; Jennifer M.; (Glastonbury, CT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Kidde Technologies, Inc. |
Wilscon |
NC |
US |
|
|
Family ID: |
65911063 |
Appl. No.: |
15/936073 |
Filed: |
March 26, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G08B 17/113 20130101;
G01N 21/01 20130101; G01N 33/0027 20130101; G01N 21/53 20130101;
G01N 2021/0106 20130101; G08B 17/107 20130101 |
International
Class: |
G01N 21/53 20060101
G01N021/53; G01N 33/00 20060101 G01N033/00; G01N 21/01 20060101
G01N021/01 |
Claims
1. A covered chamberless particulate detector comprising: a
chamberless detector configured to produce a signal when
particulate sensing events occurs; one or more optical emitters
disposed on the chamberless detector, configured to emit one or
more emitting cones of light; one or more optical sensors disposed
on the chamberless detector, defining one or more receiving cones;
and a protective cover defining an inside region and an outside
region, the protective cover disposed on the chamberless detector;
wherein each of the one or more optical sensors is configured to
detect occurrence of the particulate sensing events.
2. The covered chamberless particulate detector of claim 1, wherein
each of the one or more emitting cones of light is configured to
overlap with each of the one or more receiving cones, thereby
creating one or more sensing volumes.
3. The covered chamberless particulate detector of claim 2, further
configured to create one or more of the sensing volumes in the
inside region.
4. The covered chamberless particulate detector of claim 2, further
configured to create one or more of the sensing volumes in the
outside region.
5. The covered chamberless particulate detector of claim 1, wherein
the one or more optical emitters comprises two optical emitters,
each configured to emit a different wavelength of light.
6. The covered chamberless particulate detector of claim 1, wherein
the one or more optical sensors comprises two optical sensors, each
configured to detect a different wavelength of light.
7. The covered chamberless particulate detector of claim 1, wherein
the protective cover comprises a material that has a transparency
of at least 40%.
8. The covered chamberless particulate detector of claim 1, wherein
the protective cover has a plurality of apertures therethrough, the
apertures configured to: permit light from each of the one or more
emitting cones of light to illuminate the outside region; permit
light from the outside region to enter the inside region; and
permit fluid communication between the outside region and the
inside region.
9. The covered chamberless particulate detector of claim 8, wherein
the plurality of apertures are configured in a geometrical pattern
selected from the group consisting of: parallel latitudes and
meridian longitudes.
10. The covered chamberless particulate detector of claim 1,
wherein a ratio of a surface area of the apertures to a total
surface area of the protective cover is at least 40%.
11. The covered chamberless particulate detector of claim 1,
wherein the protective cover comprises a material that is selected
from the group consisting of: glass, plastic, polymer, fiberglass,
resin, and metal.
12. The covered chamberless particulate detector of claim 1,
wherein an inside surface of the protective cover has a
reflectivity that is less than 4%.
13. The covered chamberless particulate detector of claim 1,
further comprising a protective cover rim, the protective cover rim
disposed on the protective cover in a region where the protective
cover matingly attaches to the chamberless detector.
14. The covered chamberless particulate detector of claim 12,
further comprising a plurality of protective cover rim apertures
disposed on the protective cover rim, the protective cover rim
apertures configured to receive a connector for attaching the
protective cover to the chamberless detector.
15. A method of using a covered chamberless particulate detector
that comprises one or more optical emitters, one or more optical
sensors, and a protective cover over the optical emitters and the
optical sensors that defines an inside region and an outside
region, the method comprising: emitting one or more emitting cones
of light from the one or more optical emitters; receiving light in
one or more receiving cones by the one or more optical sensors; and
detecting particulate sensing events, and producing a signal
denoting occurrence of the particular sensing events, based on
presence of particulate material in one or more sensing volumes
defined by an overlap of the one or more emitting cones of light
and the one or more receiving cones; wherein the one or more
sensing volumes are located in the inside region, the outside
region, or both the inside region and the outside region.
16. The method of claim 15, wherein the one or more sensing volumes
are created in the inside region.
17. The method of claim 15, wherein the one or more sensing volumes
are created in the outside region.
18. The method of claim 15, wherein the protective cover has a
plurality of apertures therethrough, the apertures configured to:
permit light from each of the one or more emitting cones of light
to illuminate the outside region; permit light from the outside
region to enter the inside region; and permit fluid communication
between the outside region and the inside region.
19. The method of claim 15, wherein a ratio of a surface area of
the apertures to a total surface area of the protective cover is at
least 97%.
20. The method of claim 15, wherein the protective cover comprises
a material that has a transparency of at least 90%.
Description
BACKGROUND
[0001] The present disclosure relates generally to particulate
monitors and smoke detectors, and more particularly, to a
protective cover for a chamberless point sensor.
[0002] Smoke detectors play an important role in identifying smoke,
ideally alarming as early as possible in the course of fire. Smoke
detectors can use one or more sources of light as the source of the
smoke detection scheme, and can use multiple wavelengths of light
to help improve detection performance. For example, dual
wavelengths of light, one being infrared and the other being
visible, can be used in a smoke detector. A chamberless detector
can provide improved sensing performance over designs that utilize
a chamber, therefore resulting in the popularity of the chamberless
design in high-performance applications. A chamberless detector can
be referred to as a next-generation point sensor, because of its
advanced design and its use in detecting smoke at a particular
point of installation. A chamberless detector can also be referred
to as a chamberless point sensor. A commercial aircraft is a
non-limiting example of a high-performance application where a
chamberless point sensor utilizing multiple wavelengths of light
can be used. There are many factors that contribute to the need for
a high-performance chamberless detector, with non-limiting examples
including the desire to discern between steam or dust and the smoke
particles from a fire, the desire to avoid nuisance alarms from
food preparation, and the desire to detect smoke particles that can
be produced from smoldering synthetic materials, often resulting in
particle sizes smaller than 0.5 .mu.m (microns) in diameter.
Additionally, chamberless detectors utilizing multiple wavelengths
of light can be used to monitor indoor air quality, where fine
particles (particle sizes .ltoreq.2.5 .mu.m) and coarse particles
(particle sizes .ltoreq.10 .mu.m) can be important.
[0003] Despite the many advantages of a chamberless detector, there
are a few problems that need to be overcome. For example, in not
having a chamber, there is not a well-protected volume that is free
from interference or tampering. Additionally, the optical emitters
of a next-generation point sensor can cast light into the
surrounding environment, where it can be a source of annoyance.
Moreover, the optical detectors of a next-generation point sensor
can be prone to interference from ambient light sources emanating
from the surrounding environment.
SUMMARY
[0004] According to one embodiment of the present disclosure, a
covered chamberless particulate detector includes a chamberless
detector configured to produce a signal when particulate sensing
events occurs, one or more optical emitters on the chamberless
detector configured to emit one or more emitting cones of light,
one or more optical sensors on the chamberless detector defining
one or more receiving cones, and a protective cover on the
chamberless detector defining an inside region and an outside
region. Each optical sensor is configured to detect the occurrence
of particulate sensing events, and each of the one or more emitting
cones of light is configured to overlap with each of the one or
more receiving cones, thereby creating one or more sensing
volumes.
[0005] According to another embodiment of the present disclosure, a
method of using a covered chamberless particulate detector that
includes one or more optical emitters, one or more optical sensors,
and a protective cover over the optical emitters and the optical
sensors that defines an inside region and an outside region. The
method includes emitting one or more emitting cones of light from
the one or more optical emitters, receiving light in one or more
receiving cones by the one or more optical sensors, detecting
particulate sensing events, and producing a signal denoting
occurrence of the particular sensing events. The detecting is based
on the presence of particulate material in one or more sensing
volumes defined by an overlap of the one or more emitting cones of
light and the one or more receiving cones, where the one or more
sensing volumes are located in the inside region, the outside
region, or both the inside region and the outside region.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a side view of a next generation chamberless
particulate detector with one embodiment of the protective
cover.
[0007] FIG. 2 is a perspective view of a second embodiment of the
protective cover.
[0008] FIG. 3 is a perspective view of a third embodiment of the
protective cover.
[0009] FIG. 4 is a perspective view of a fourth embodiment of the
protective cover.
[0010] FIG. 5 is a perspective view of a fifth embodiment of the
protective cover.
[0011] FIG. 6 is a perspective view of a sixth embodiment of the
protective cover.
[0012] FIG. 7 is a perspective view of a seventh embodiment of the
protective cover.
[0013] FIG. 8 is a perspective view of an eighth embodiment of the
protective cover.
DETAILED DESCRIPTION
[0014] The present disclosure provides a protective cover for a
next generation chamberless point sensor. As used in this
disclosure, the next generation chamberless point sensor can be
referred to as a chamberless point sensor and monitor, covered
chamberless particulate detector, or chamberless detector for
short. As used in this disclosure, "particulate" will be used to
describe all airborne particles that are detectable, which includes
smoke. Moreover, the descriptions provided herein refer to the
detection of airborne particulates by the interaction of light and
the scattering of light to the optical detection circuitry of the
chamberless detector. The operation of a chamberless detector can
be referred to as monitoring, whereby the chamberless detector
monitors for sensing events. A sensing event is when an electrical
response occurs within the detection circuitry as a result of a
photo interaction.
[0015] FIG. 1 is a side view of a chamberless particulate detector
with a protective cover. Shown in FIG. 1 are covered point sensor
10, chamberless detector 12, optical sources 14, optical sensors
16, mounting rim 20, emitting cone 22, receiving cone 23, near
particles 24, far particles 26, inside region 29, protective cover
30, and outside region 31. As will be described in this disclosure,
emitting cone 22 is associated with each optical source 14, and
receiving cone 23 is associated with each optical sensor 16. The
exemplary embodiment illustrated in FIG. 1 depicts two optical
sources 14 and two optical sensors 16, but only one emitting cone
22 and one receiving cone 23 is shown for ease of illustration.
[0016] In the illustrated embodiment, covered point sensor 10 has a
substantially hemispherical geometry, being comprised of
chamberless detector 12 and protective cover 30. Chamberless
detector 12 has a substantially flat profile as illustrated in the
side view of FIG. 1. In the illustrated embodiment, chamberless
detector 12 has a circular or disk-like shape viewed from the top
or in perspective (not shown). In the illustrated embodiment,
protective cover 30 has a semi-circular shape as viewed from the
side. Protective cover 30 can be referred to as an envelope,
defining an inside region and an outside region of protective cover
30. In the illustrated embodiment, protective cover 30 has a
diameter of about 10 cm (3.9 inches) in the region near where
protective cover 30 attaches to chamberless detector 12. In other
embodiments, protective cover 30 can have a diameter between 5-15
cm (2.0-5.9 inches). In yet other embodiments, protective cover 30
can have a diameter of less than 5 cm (2.0 inches), or greater than
15 cm (5.9 inches). In the illustrated embodiment, protective cover
30 has a generally hemispherical shape, in which the height of
protective cover 30 is approximately half the diameter. In other
embodiments, the geometry of protective cover 30 can be
substantially different from hemispherical. For example, in an
embodiment, protective cover 30 can be squat in its geometry, with
a height less than approximately half the diameter. In another
embodiment, the height of protective cover 30 can be significantly
less than approximately half the diameter. Alternatively, in yet
other embodiments, protective cover 30 can have a bulbous geometry,
in which the height of protective cover 30 is greater than
approximately half the diameter. In other embodiments, the cover
can be cylindrical, square, or rectangular in shape, with these
being non-limiting examples of possible geometries of protective
cover 30.
[0017] In the illustrated embodiment, covered point sensor 10
includes chamberless detector 12 and protective cover 30. It will
be appreciated that covered point sensor 10 can provide additional
benefits including but not limited to reduction of transport time
for particles to reach the particle detecting elements to enable
faster alerting, alarm, and response by users and systems; improved
sensitivity; improved manufacturability; negligible directionality;
ease of maintenance; and enhanced aesthetic appearance.
[0018] Optical emitters 14 produce and emit light having a
wavelength or wavelengths that are employed by chamberless detector
12. In the illustrated embodiment there are two optical emitters
14, with each optical emitter producing a peak wavelength of light.
In an embodiment, a first optical emitter 14 can produce an
infrared light and a second optical emitter 14 can produce a blue
light. The infrared light can have a peak wavelength between
800-950 nm, but in some embodiments may be outside of this range.
The blue light can have a peak wavelength between 460-480 nm, but
in some embodiments may be outside of this range. In some
embodiments, optical emitters 14 can produce wavelengths of light
in the infrared, visible, and ultraviolet bands of light. In these
other embodiments, optical emitters 14 can produce a wide range of
wavelengths of light. For example, in an embodiment, one or more
optical emitters 14 can produce violet or ultraviolet light having
a wavelength shorter than 460 nm. In another embodiment, one or
more optical emitters 14 can produce visible light having a
wavelength between 380-700 nm. In yet other embodiments, one or
more optical emitters 14 can produce infrared light having a
wavelength greater than 700 nm. In some embodiments, optical
emitters 14 can produce the same wavelength of light. In some
embodiments, only one optical emitter 14 can be used. In other
embodiments, three or more optical emitters 14 can be used. In the
illustrated embodiment, optical emitters 14 are light emitting
diodes (LEDs). In other embodiments, optical emitters 14 can
produce light by any suitable means.
[0019] Referring again to FIG. 1, optical emitter 14 produces and
emits light as emitting cone 22. Emitting cone 22 is an expanding
cone of light that is emitted from optical emitter 14 at one or
more wavelengths of light. In the illustrated embodiment, two
optical emitters 14 are shown but for simplicity of illustration,
only one emitting cone 22 is illustrated being emitted from a first
optical emitter. It should be recognized that each optical emitter
14 will produce and emit a separate emitting cone 22, although they
can be placed adjacent to each other and therefore have overlapping
emitting cones 22. In some embodiments, multiple emitting cones 22
can be produced from a single optical emitter 14, and each of the
multiple emitting cones 22 can have similar or different optical
properties. In the illustrated embodiment, emitting cone 22 is
projected into a volume of the space being monitored by covered
point sensor 10, with emitting cone 22 having a dispersion angle
that results in an expansion of emitting cone 22 at greater
distances from optical emitter 14.
[0020] Optical sensors 16 detect light. Two optical sensors 16 are
depicted in the present embodiment. In some embodiments, one
optical sensor 16 can be used. In other embodiments, three or more
optical sensors 16 can be used. In the illustrated embodiment,
optical sensors 16 are photo diodes. In other embodiments, optical
sensors 16 can be any suitable device that produces a photoelectric
indication of light. In other embodiments, a single optical sensor
16 can be used, or three or more optical sensors 16 can be used. In
some embodiments, the two or more optical sensors 16 can be the
same style of photo detector, or can be different styles of photo
detectors from each other. In some embodiments, each optical sensor
16 can be responsive to a particular wavelength of light.
[0021] Each optical sensor has a corresponding receiving cone 23,
depicting the field of view of the particular optical sensor 16,
with a single receiving cone 23 being shown for ease of
illustration. Receiving cone 23 is an expanding cone defining the
region that optical sensor 16 is sensitive to. In some embodiments,
a particular optical sensor 16 can have two or more optical cones
23, and each particular optical cone can have different geometries
and/or be responsive to different wavelengths of light.
[0022] The volume where a particular emitting cone 22 and a
particular receiving cone 23 overlap is referred to as a sensing
volume. One or more sensing volumes can be created by the
interaction of a single emitting cone 22 with a single receiving
cone 23, the interaction of a single emitting cone 22 with two or
more receiving cones 23, by the interaction of two or more emitting
cones 22 with a single receiving cone 23, or by the interaction of
two or more emitting cones 22 with two or more receiving cones 23.
In the illustrated embodiment, protective cover 30 is transparent.
Accordingly, any of the multiple sensing volumes created by covered
point sensor 10 as described above can be entirely in inside region
29, outside region 31, or in both inside region 29 and outside
region 31. In some embodiments there can be fluid communication
from the region outside protective cover 30 to inside protective
cover 30.
[0023] As shown in FIG. 1, exemplary near particles 24 are located
in inside region 29, and exemplary far particles 26 are located in
outside region 31. As will be described in FIGS. 2-8, various
embodiments of protective cover 30 are available to allow for fluid
communication between outside region 31 and inside region 29.
Exemplary near particles 24 are located in inside region 29, and
exemplary far particles 26 are located in outside region 31.
Generally speaking, particulates, including smoke and other
airborne particles, can vary in size depending on several factors
including without limitation the materials that are smoldering,
burning, or combusting, the temperature of the process, the stage
of the process, and the concentration of oxygen and other gasses at
the point of the process. The process can be combustion,
pre-combustion, or any other process that evolves airborne
particulates. Moreover, processes other than combustion can cause
airborne particulates. For example, chemical reactions can evolve
airborne particulates. Particulates can generally range in size
from 0.1-2.0 .mu.m in diameter, however they can be smaller in size
than 0.1 .mu.m in diameter, or larger in size than 2.0 .mu.m in
diameter. Some particulates can be up to 10 .mu.m in diameter. In
some embodiments, covered point sensor 10 can monitor for indoor
air quality, while being able to discriminate between fine
particles (particle sizes .ltoreq.2.5 .mu.m) and coarse particles
(particle sizes .ltoreq.10 .mu.m).
[0024] As described above, each optical sensor 16 has receiving
cone 23. The geometry of each receiving cone 23 depends on the
field of view, position, and alignment of respective optical sensor
16. Accordingly, the intersection of receiving cone 23 of optical
sensor 16, and emitting cone 22 of optical emitter 14, determines
the sensing volume, as described above. In a typical embodiment,
multiple sensing volumes are created by covered point sensor 10,
with each sensing volume determining where particulates can be
detected. Covered point sensor 10 detects the presence of
particulates by the scattering of light in each of the sensing
volumes, as described above. As light illuminates near particles 24
and/or far particles 26, scattering and/or fluorescence occurs.
Some of the scattered and/or fluoresced light within each sensing
volume is directed to optical sensor 16. The light received by
optical sensor 16 causes an electrical reaction in optical sensor
16 which is amplified and analyzed by detection circuitry (not
shown) within covered point sensor 10. Accordingly, the electrical
signal produced by each optical sensor 16 is received by circuitry
(not shown) of covered point sensor 10, thereby producing a sensing
event. The processing of these electrical signals that are produced
by sensing events can be referred to as monitoring, as described
above. During the monitoring process, one or more levels produced
by the monitor can be displayed on an indicator and/or recorded on
a data storage medium. Moreover, different monitored levels can be
produced in response to various detection wavelengths and other
factors. The covered point sensor 10 can be programmed to
discriminate between various sensing events, while producing
additional responses if various threshold criteria are met.
Non-limiting examples of additional responses can include
activating an alarm, triggering other system responses, and
initiating protective actions.
[0025] As will be described in FIGS. 2-8, several factors can
influence the ability of particulates to enter inside region 29,
thereby being detectable in sensing volumes in inside region 29.
Similarly, several factors can affect the ability of covered point
sensor 10 to detect particulates in outside region 31. Non-limiting
examples of these several factors include the size and shape of
protective cover 30, the transparency of protective cover 30, the
use of mesh/openings/slots/openings on protective cover 30, and the
degree of fluid communication from outside region 31 to inside
region 29.
[0026] Mounting rim 20 surrounds the outer peripheral edge of
chamberless detector 12 in the region where protective cover 30
attaches to chamberless detector 12. Similarly, protective cover
rim 32 surrounds the outer peripheral edge of protective cover 30
in the region where protective cover 30 attaches to chamberless
detector 12. In the illustrated embodiment, mounting rim 20 fully
surrounds chamberless detector 12, and protective cover rim 32
fully surrounds protective cover 30, and a removable adhesive can
be used to affix protective cover rim 32 to mounting rim 20,
thereby affixing protective cover 30 to chamberless detector 12. In
other embodiments, a means of fastening protective cover 30 to
chamberless detector 12 may be provided. For example, threaded
fasteners could be used to affix protective cover 30 to chamberless
detector 12. In some embodiments, a distinctive mounting rim 20 may
not exist on chamberless detector 12, and/or a distinctive
protective cover rim 32 may not exist on protective cover 30. In
these embodiments, any suitable means of affixing protective cover
20 to chamberless detector 12 may be employed. Non-limiting
examples include friction-fit, snap-fit, twist lock, touch
fasteners, threaded fasteners, and permanent adhesives. In other
embodiments, mounting rim 20 may only partially surround
chamberless detector 12, and/or protective cover rim 32 may only
partially surround mounting rim 30. In these other embodiments, for
example, tabs, hooks, snaps, feet, or the like may take the place
of affixing protective cover 32 to mounting rim 20.
[0027] FIGS. 2-8 disclose various embodiments of protective cover
30 as shown in FIG. 1. In the description of FIGS. 2-8, references
to emitting cone 22, receiving cone 23, near particles 24, far
particles 26, inside region 29, and outside region 31 will be as
shown in FIG. 1.
[0028] FIG. 2 is a perspective view of a second embodiment of the
protective cover of covered point sensor 10. Shown in FIG. 2 are
protective cover 130, protective cover rim 132, protective cover
material 134, and protective cover apertures 136. Protective cover
130 is formed from a structure of protective cover material 134,
with a lattice of protective cover apertures 136 in the
non-material regions. In the illustrated embodiment, protective
cover material 134 includes stands of wire that are woven together
and formed into the dome-like structure of protective cover 130. In
other embodiments, protective cover material 134 can be any
metallic or non-metallic material, with non-limiting examples
including glass, plastic, fiberglass, resin, and metal. In the
illustrated embodiment, protective cover material 134 is
anti-reflective, such that light from emitting cone 22 is not
reflected within protective cover 130. In other embodiments,
protective cover material 134 can be transparent, reflective,
anti-reflective, and/or absorptive.
[0029] In the illustrated embodiment, protective cover apertures
136 can allow for light from optical emitters 14 to pass from
inside region 29 into outside region 31, thereby illuminating
particulates in outside region 31. Protective cover apertures 136
can also allow for scattered light from particulates in outside
region 31 to pass from outside region 31 to inside region 29,
thereby entering one or more receiving cones 23 of optical sensors
16. Accordingly, one or more sensing volumes can be created in
outside region 31. Protective cover apertures 136 can also permit
fluid communication between outside region 31 and inside region 29,
thereby allowing particulates to enter inside region 29. Particles
in inside region 29 can be detected by covered point sensor in one
or more sensing volumes that are created in inside region 29. In
the illustrated embodiment, protective cover material 134 covers
between about 1-3% of the surface area of protective cover 130. In
some embodiments, protective cover material 134 can cover less than
1% of the surface area of protective cover 130. In yet other
embodiments, protective cover material 134 can cover more than 3%
of the surface area of protective cover 130.
[0030] FIG. 3 is a perspective view of a third embodiment of the
protective cover of covered point sensor 10. Shown in FIG. 3 are
protective cover 230, protective cover rim 232, protective cover
material 234, protective cover apertures 236, and protective cover
inner surface 238. Protective cover 230 is formed from a structure
of protective cover material 234, with a lattice of protective
cover apertures 236 in the non-material regions. In the illustrated
embodiment, protective cover material 234 is a lattice structure of
metal that is formed into the dome-like structure of protective
cover 230. In other embodiments, protective cover material 234 can
be any metallic or non-metallic material, with non-limiting
examples including plastic, fiberglass, and resin. The lattice of
protective cover material 234 can be formed by punching, drilling,
etching, or burning protective cover apertures 236 into protective
cover material 234. In the illustrated embodiment, protective cover
inner surface 238 is anti-reflective, such that light from emitting
cone 22 is not reflected within protective cover 230. In other
embodiments, protective cover inner surface 238 can be reflective
or partially reflective. In some embodiments, protective cover
material 234 can be transparent, reflective, anti-reflective,
and/or absorptive. Protective cover apertures 236 can function
similar to protective cover apertures 136 described in FIG. 1.
[0031] FIG. 4 is a perspective view of a fourth embodiment of the
protective cover of covered point sensor 10. Shown in FIG. 4 are
protective cover 330, protective cover rim 332, protective cover
material 334, protective cover apertures 336, protective cover
inner surface 338, and protective cover rim apertures 340.
Protective cover 330 is formed from a structure of protective cover
material 334, with a structure of protective cover apertures 336 in
the non-material regions. In the illustrated embodiment, protective
cover material 334 is a material structure of plastic that is
molded into the dome-like structure of protective cover 330. In
other embodiments, protective cover material 334 can be any
metallic or non-metallic material, with non-limiting examples
including metal, fiberglass, and resin. In the illustrated
embodiment, protective cover apertures 336 are molded into
protective cover 330. In other embodiments, protective cover
apertures 336 can be formed by punching, cutting, etching, or
burning protective cover apertures 336 into protective cover
material 334. In the illustrated embodiment, protective cover inner
surface 338 is anti-reflective, such that light from emitting cone
22 is not reflected within protective cover 330. In other
embodiments, protective cover inner surface 338 can be reflective
or partially reflective. In some embodiments, protective cover
material 334 can be transparent, reflective, anti-reflective,
and/or absorptive.
[0032] Protective cover apertures 336 can function similar to
protective cover apertures 136 described in FIG. 1. In the
illustrated embodiment, protective cover material 334 covers
between about 40-60% of the surface area of protective cover 330.
In some embodiments, protective cover material 334 can cover less
than 40% of the surface area of protective cover 330. In yet other
embodiments, protective cover material 334 can cover more than 60%
of the surface area of protective cover 330. Protective cover rim
apertures 340 can be used for affixing protective cover 330 to
mounting rim 20 by the use of mechanical fastening devices.
Non-limiting examples of mechanical fastening devices include pins,
threaded fasteners, studs, and rivets.
[0033] FIG. 5 is a perspective view of a fifth embodiment of the
protective cover of covered point sensor 10. Shown in FIG. 5 are
protective cover 430, protective cover rim 432, protective cover
material 434, and protective cover apertures 436. Protective cover
430 is formed from protective cover material 434, with an array of
protective cover apertures 436 that are arranged as parallel
latitudes in some regions of protective cover 430. In the
illustrated embodiment, protective cover material 434 is
transparent plastic material in the form of a dome-like structure
for protective cover 430. Accordingly, protective cover 430 can
allow light transmission similar to that described in FIG. 1. As
use in this disclosure, transparent is defined to mean the material
has a transparency of at least 90% at the wavelength or wavelengths
of light being transmitted through protective cover 430. In other
embodiments, protective cover material 434 can be any transparent
or substantially transparent material such as glass or resin. In
yet other embodiments, protective cover material 434 can be a
partially transparent material. As use in this disclosure,
partially transparent is defined to mean the material has a
transparency of 40-90% at the wavelength or wavelengths of light
being transmitted. In some embodiments, protective cover material
434 can be transparent, reflective, anti-reflective, and/or
absorptive.
[0034] Protective cover apertures 436 can be formed by molding,
punching, cutting, etching, or burning protective cover material
434. Protective cover apertures 436 can function similar to
protective cover apertures 136 described in FIG. 1. In the
illustrated embodiment, protective cover apertures 436 are arranged
as parallel latitudes. In other embodiments, the shape, size, and
orientation of protective cover apertures 436 can be of any
geometry. In the illustrated embodiment, protective cover apertures
436 cover between about 2-10% of the surface area of protective
cover 430. In some embodiments, protective cover apertures 436 can
cover less than 2% of the surface area of protective cover 430. In
yet other embodiments, protective cover apertures 436 can cover
more than 10% of the surface area of protective cover 430.
Protective cover apertures 436 can function similar to protective
cover apertures 136 described in FIG. 1.
[0035] FIG. 6 is a perspective view of a sixth embodiment of the
protective cover of covered point sensor 10. Shown in FIG. 6 are
protective cover 530, protective cover rim 532, protective cover
material 534, and protective cover apertures 536. Protective cover
530 is formed from protective cover material 534, with an array of
protective cover apertures 536 that are arranged as meridian
longitudes in some regions of protective cover 530. Protective
cover apertures 536 can be formed by molding, punching, cutting,
etching, or burning protective cover material 534. In the
illustrated embodiment, protective cover apertures 536 are arranged
as meridian longitudes. In other embodiments, the shape, size, and
orientation of protective cover apertures 536 can be of any
geometry. In the illustrated embodiment, protective cover material
534 is transparent plastic material in the form of a dome-like
structure for protective cover 530. In other embodiments,
protective cover material 534 can be any transparent material such
as glass, polymer, or resin. In yet other embodiments, protective
cover material 534 can be a partially transparent material. In the
illustrated embodiment, protective cover material 534 is
transparent. Accordingly, protective cover 430 can allow light
transmission similar to that described in FIG. 1. In some
embodiments, protective cover material 334 can be transparent,
reflective, anti-reflective, and/or absorptive.
[0036] In the illustrated embodiment, protective cover apertures
536 cover between about 2-10% of the surface area of protective
cover 530. In some embodiments, protective cover apertures 536 can
cover less than 2% of the surface area of protective cover 530. In
yet other embodiments, protective cover apertures 536 can cover
more than 10% of the surface area of protective cover 530.
Protective cover apertures 536 can function similar to protective
cover apertures 136 described in FIG. 1.
[0037] FIG. 7 is a perspective view of a seventh embodiment of the
protective cover of covered point sensor 10. Shown in FIG. 7 are
protective cover 630, protective cover rim 632, protective cover
material 634, and protective cover apertures 636. Protective cover
630 is formed from protective cover material 634, with an array of
protective cover apertures 636 that are arranged as parallel
latitudes in some regions of protective cover 630. In the
illustrated embodiment, protective cover material 634 is an opaque
material in the form of a dome-like structure for protective cover
630. As use in this disclosure, opaque is defined to mean the
material has a transparency less than of 40% at the wavelength or
wavelengths of light being transmitted.
[0038] In other embodiments, protective cover material 634 can be
any opaque material such as resin or metal. In yet other
embodiments, protective cover material 634 can be a partially
opaque material. Protective cover apertures 636 can be formed by
molding, punching, cutting, etching, or burning protective cover
material 634. In the illustrated embodiment, protective cover
material 634 is opaque, thereby preventing or restricting the
transmission of light from emitting cone 22 to pass through
protective cover 630. The opacity of protective cover material 634
can also prevent or restrict the transmission of light from outside
region 31 into inside region 29. Sources of light from outside
region 31 can include light from optical emitters that is scattered
from particulates in outside region 31, or from ambient light
external to covered point sensor 10. Non-limiting examples of
ambient light can include light sources in the vicinity of covered
point sensor such as office, room, and cargo bay lighting, or from
direct or reflected light from other sources such as sunlight.
These various sources of ambient light can be broad or narrow bands
of light in the range of wavelengths from about 300-3000 nm.
Protective cover apertures 636 can also allow fluid communication
of particulates from outside region 31 into inside region 29, as
described earlier.
[0039] In the illustrated embodiment, protective cover apertures
636 are arranged as parallel latitudes. In other embodiments, the
shape, size, and orientation of protective cover apertures 636 can
be of any geometry. Protective cover apertures 636 can allow for
light from optical emitters 16 to pass from inside region 29 to
outside region 31, and from outside region 31 to inside region 29,
thereby allowing for sensing volumes to be created in outside
region 31. As described earlier, several factors determine the size
and location of the sensing volumes that are created by covered
point sensor 10 including the location, direction, and cone width
of emitting cones 22 and receiving cones 23. In the illustrated
embodiment, protective cover apertures 636 cover between about
2-10% of the surface area of protective cover 630. In some
embodiments, protective cover apertures 636 can cover less than 2%
of the surface area of protective cover 630. In yet other
embodiments, protective cover apertures 636 can cover more than 10%
of the surface area of protective cover 630.
[0040] FIG. 8 is a perspective view of an eighth embodiment of the
protective cover of covered point sensor 10. Shown in FIG. 8 are
protective cover 730, protective cover rim 732, protective cover
material 734, and protective cover apertures 736. Protective cover
730 is formed from protective cover material 734, with an array of
protective cover apertures 736 that are arranged as meridian
longitudes in some regions of protective cover 730. In the
illustrated embodiment, protective cover material 734 is an opaque
material in the form of a dome-like structure for protective cover
730. In other embodiments, protective cover material 734 can be any
opaque material such as resin or metal. In yet other embodiments,
protective cover material 734 can be a partially opaque material.
Protective cover apertures 736 can be formed by molding, punching,
cutting, etching, or burning protective cover material 734. In the
illustrated embodiment, protective cover material 734 is opaque,
thereby not allowing light from emitting cone 22 to pass through
protective cover 730. In the illustrated embodiment, protective
cover apertures 736 are arranged as meridian longitudes. In other
embodiments, the shape, size, and orientation of protective cover
apertures 736 can be of any geometry. In the illustrated
embodiment, protective cover apertures 736 cover between about
2-10% of the surface area of protective cover 730. In some
embodiments, protective cover apertures 736 can cover less than 2%
of the surface area of protective cover 730. In yet other
embodiments, protective cover apertures 736 can cover more than 10%
of the surface area of protective cover 730. Protective cover
apertures 736 can function similar to protective cover apertures
636 described in FIG. 7.
[0041] The various embodiments of protective cover 30 depicted in
FIGS. 1-8 are non-limiting, with the scope of the present
disclosure including any embodiment of a cover that is disposed on
chamberless detector 12. While the various embodiments that are
disclosed herein generally depict protective cover 30 as being
round and symmetrical in shape, other geometries of protective
cover 30 are within the scope of the present disclosure. Moreover,
the various embodiments that are disclosed herein generally depict
protective cover 30 as entirely covering chamberless detector 12,
with apertures generally having a uniform distribution. However, a
partial protective cover 30 is within the scope of the present
disclosure. Moreover, aperture arrangements that are non-uniform in
size and/or shape and/or coverage are also within the scope of the
present disclosure.
Discussion of Possible Embodiments
[0042] The following are non-exclusive descriptions of possible
embodiments of the present invention.
[0043] A covered chamberless particulate detector comprises a
chamberless detector configured to produce a signal when
particulate sensing events occurs, one or more optical emitters
disposed on the chamberless detector and configured to emit one or
more emitting cones of light, one or more optical sensors disposed
on the chamberless detector defining one or more receiving cones,
and a protective cover disposed on the chamberless detector and
defining an inside region and an outside region, wherein each of
the one or more optical sensors is configured to detect occurrence
of the particulate sensing events.
[0044] The covered chamberless particulate detector of the
preceding paragraph can optionally include, additionally and/or
alternatively, any one or more of the following features,
configurations and/or additional components:
[0045] A further embodiment of the foregoing covered chamberless
particulate detector, wherein each of the one or more emitting
cones of light is configured to overlap with each of the one or
more receiving cones, thereby creating one or more sensing
volumes.
[0046] A further embodiment of the foregoing covered chamberless
particulate detector, further configured to create one or more of
the sensing volumes in the inside region.
[0047] A further embodiment of the foregoing covered chamberless
particulate detector, further configured to create one or more of
the sensing volumes in the outside region.
[0048] A further embodiment of the foregoing covered chamberless
particulate detector, wherein the one or more optical emitters
comprises two optical emitters, each configured to emit a different
wavelength of light.
[0049] A further embodiment of the foregoing covered chamberless
particulate detector, wherein the one or more optical sensors
comprises two optical sensors, each configured to detect a
different wavelength of light.
[0050] A further embodiment of the foregoing covered chamberless
particulate detector, wherein the protective cover comprises a
material that has a transparency of at least 40%.
[0051] A further embodiment of the foregoing covered chamberless
particulate detector, wherein the protective cover has a plurality
of apertures therethrough, the apertures configured to: permit
light from each of the one or more emitting cones of light to
illuminate the outside region; permit light from the outside region
to enter the inside region; and permit fluid communication between
the outside region and the inside region.
[0052] A further embodiment of the foregoing covered chamberless
particulate detector, wherein the plurality of apertures are
configured in a geometrical pattern selected from the group
consisting of: parallel latitudes and meridian longitudes.
[0053] A further embodiment of the foregoing covered chamberless
particulate detector, wherein a ratio of a surface area of the
apertures to a total surface area of the protective cover is at
least 40%.
[0054] A further embodiment of the foregoing covered chamberless
particulate detector, wherein the protective cover comprises a
material that is selected from the group consisting of: glass,
plastic, polymer, fiberglass, resin, and metal.
[0055] A further embodiment of the foregoing covered chamberless
particulate detector, wherein an inside surface of the protective
cover has a reflectivity that is less than 4%.
[0056] A further embodiment of the foregoing covered chamberless
particulate detector, further comprising a protective cover rim,
the protective cover rim disposed on the protective cover in a
region where the protective cover matingly attaches to the
chamberless detector.
[0057] A further embodiment of the foregoing covered chamberless
particulate detector, further comprising a plurality of protective
cover rim apertures disposed on the protective cover rim, the
protective cover rim apertures configured to receive a connector
for attaching the protective cover to the chamberless detector.
[0058] A further embodiment of the foregoing covered chamberless
particulate detector, wherein
[0059] A method of using a covered chamberless particulate detector
that comprises one or more optical emitters, one or more optical
sensors, and a protective cover over the optical emitters and the
optical sensors that defines an inside region and an outside
region. The method includes emitting one or more emitting cones of
light from the one or more optical emitters; receiving light in one
or more receiving cones by the one or more optical sensors; and
detecting particulate sensing events, and producing a signal
denoting occurrence of the particular sensing events, based on
presence of particulate material in one or more sensing volumes
defined by an overlap of the one or more emitting cones of light
and the one or more receiving cones; wherein the one or more
sensing volumes are located in the inside region, the outside
region, or both the inside region and the outside region.
[0060] The method of the preceding paragraph can optionally
include, additionally and/or alternatively, any one or more of the
following features, configurations and/or additional
components:
[0061] A further embodiment of the foregoing method, wherein the
one or more sensing volumes are created in the inside region.
[0062] A further embodiment of the foregoing method, wherein the
one or more sensing volumes are created in the outside region.
[0063] A further embodiment of the foregoing method, wherein the
protective cover has a plurality of apertures therethrough, the
apertures configured to: permit light from each of the one or more
emitting cones of light to illuminate the outside region; permit
light from the outside region to enter the inside region; and
permit fluid communication between the outside region and the
inside region.
[0064] A further embodiment of the foregoing method, wherein a
ratio of a surface area of the apertures to a total surface area of
the protective cover is at least 97%.
[0065] A further embodiment of the foregoing method, wherein the
protective cover comprises a material that has a transparency of at
least 90%.
[0066] While the invention has been described with reference to an
exemplary embodiment(s), it will be understood by those skilled in
the art that various changes may be made and equivalents may be
substituted for elements thereof without departing from the scope
of the invention. In addition, many modifications may be made to
adapt a particular situation or material to the teachings of the
invention without departing from the essential scope thereof.
Therefore, it is intended that the invention not be limited to the
particular embodiment(s) disclosed, but that the invention will
include all embodiments falling within the scope of the appended
claims.
* * * * *