Technical Field
[0001] The present disclosure generally relates to smoke sensors. More particularly, the
present disclosure relates to a smoke sensor configured to detect smoke.
Background Art
[0002] JP 2010-257258 A (hereinafter, referred to as a "Document 1") discloses a smoke sensor. This smoke
sensor includes a smoke sensing unit configured to optically detect smoke, using a
light emitting part and a light receiving part. The smoke sensing unit further includes
an optical base in which the light emitting part and the light receiving part are
housed. The optical base is covered with an insect net.
[0003] In the smoke sensor disclosed in the Document 1, a foreign matter may enter an inside
(detection space) of the smoke sensor through a gap between the optical base (board)
and a detection cover where the insect net is provided. For this reason, the smoke
sensor has a problem that a false detection may occur due to the foreign matter entering
the inside.
Summary of Invention
[0004] It is therefore an object of the present disclosure to provide a smoke sensor, which
can contribute to reducing a chance of a false detection due to a foreign matter.
[0005] A smoke sensor according to an aspect of the present disclosure includes a housing,
a detecting unit, a partition, a board, a detection cover having a tubular shape with
bottom, and a suppressor. The housing has an opening through which smoke flows into
the housing from an outside of the housing. The detecting unit is configured to detect
the smoke in a detection space provided in an inside of the housing. The partition
is configured to divide the inside of the housing. On the board, the detecting unit
is disposed. The detection cover is configured to house the detecting unit. The suppressor
is disposed at a peripheral edge of an end of the detection cover and configured to
suppress a foreign matter from entering the detection space from the outside. The
detection space is a space formed by the board and the detection cover. The suppressor
is disposed between the board and the partition. The suppressor is at least partially
in contact with the board.
Brief Description of Drawings
[0006]
FIG. 1 is an appearance perspective view of a smoke sensor, when viewed from above,
according to a first embodiment;
FIG. 2 is a cross-sectional view of the smoke sensor;
FIG. 3 is an exploded perspective view of the smoke sensor, when viewed from above;
FIG. 4 is an appearance perspective view of a body portion of the smoke sensor, when
viewed from below;
FIG. 5 is a schematic cross-sectional view of an essential part of the smoke sensor;
FIG. 6 is a schematic cross-sectional view of an essential part in a first variation
of the smoke sensor;
FIG. 7A is a schematic cross-sectional view of an essential part in a second variation
of the smoke sensor;
FIG. 7B is a schematic cross-sectional view of the essential part in the second variation
of the smoke sensor;
FIG. 8A is a schematic cross-sectional view of an essential part in a third variation
of the smoke sensor;
FIG. 8B is a schematic cross-sectional view of the essential part in the third variation
of the smoke sensor;
FIG. 8C is a schematic cross-sectional view of the essential part in the third variation
of the smoke sensor;
FIG. 9A is a schematic cross-sectional view of an essential part in a smoke sensor
according to a second embodiment;
FIG. 9B is a schematic cross-sectional view of an essential part in a variation of
the smoke sensor;
FIG. 10A is a schematic cross-sectional view of an essential part in a smoke sensor
according to a third embodiment;
FIG. 10B is a schematic cross-sectional view of an essential part in a variation of
the smoke sensor; and
FIG. 10C is a schematic cross-sectional view of the essential part in the variation
of the smoke sensor.
Description of Embodiments
[0007] A smoke sensor according to each of exemplary embodiments of the present disclosure
will be described with reference to the drawings. The drawings to be referred to in
the following embodiments are all schematic representations. That is to say, the ratio
of the dimensions (including thicknesses) of respective constituent elements illustrated
on the drawings does not always reflect their actual dimensional ratio.
(1) First Embodiment
(1-1) Overview
[0008] Hereinafter, an overview of a smoke sensor 100 according to a first embodiment will
be described with reference to FIGS. 1 to 3.
[0009] The smoke sensor 100 (refer to FIG. 1) according to the first embodiment is a disaster
protection device that calls, when sensing smoke generated by a fire or any other
event, an alert for the fire. That is to say, when the smoke is generated in response
to occurrence of a disaster such as the fire, the smoke sensor 100 senses the smoke
and calls the alert, for example, by outputting an alarm sound or by interconnecting
with another device, using a communication function. The "disaster protection device"
mentioned in the present disclosure may be a device installed in a facility, for example,
for the purpose of preventing the disaster such as the fire, preventing the spread
of damage caused by the disaster, or recovering from the disaster.
[0010] The smoke sensor 100 is installed and used in the facility. In the present embodiment,
the smoke sensor 100 is exemplified when used in a non-residential facility such as,
for example, a hotel, an office building, a school building, a welfare facility, a
commercial facility, a theme park, a hospital, or a factory. Of course, not limited
to this example, the smoke sensor 100 may be used in a facility such as a multi-family
dwelling house or a single-family dwelling house. The smoke sensor 100 may be installed
in the facility with being attached to a ceiling or a wall in a place such as a room,
corridor or staircase, of the facility.
[0011] As shown in FIGS 1 to 3, the smoke sensor 100 includes a housing 1, a detecting unit
20, a partition 3, a board 41, a detection cover 21 and a suppressor 5.
[0012] As shown in FIG. 1, the housing 1 has an opening 101 through which smoke flows into
the housing 1 from an outside of the housing 1. That is to say, when the smoke is
generated by the fire or any other event, the smoke generated is allowed to enter
the housing 1 through the opening 101.
[0013] The detecting unit 20 (refer to FIG. 3) is configured to detect the smoke in a detection
space Sp1 (refer to FIG. 2) provided in an inside of the housing 1. The partition
3 is configured to divide the inside of the housing 1. On the board 41, the detecting
unit 20 is disposed. The detection cover 21 is configured to house the detecting unit
20. The detection cover 21 has a tubular shape with bottom. The suppressor 5 is disposed
at a peripheral edge of an end of the detection cover 21, and configured to suppress
a foreign matter from entering the detection space Sp1 from the outside. The detection
space Sp1 is a space formed by the board 41 and the detection cover 21. As shown in
FIG. 2, the suppressor 5 is disposed between the board 41 and the partition 3. The
suppressor 5 is at least partially in contact with the board 41.
[0014] The "foreign matter" mentioned in the present disclosure is assumed to be, for example,
an insect or a dust, and is a moving object larger than a smoke particle. In other
words, the "foreign matter" is larger than a smoke particle and in particular, a living
object that moves by itself, or an object that floats and moves by air flow, etc.
In the example that the foreign matter is the insect, the insect (flying, creeping,
or being carried in the wind) may rest on the ceiling or wall where the smoke sensor
100 is installed, or may enter the housing 1 through the opening 101. If the smoke
sensor includes no suppressor, the insect may creep along the ceiling, wall, or inner
wall of the housing to enter the detection space through a gap between the detection
cover and the board. If the insect enters the detection space, light (emitted by a
light emitting part 201 described later) may be reflected with the insect (i.e., the
foreign matter), amount of light (received by a light receiving part 202 described
later) may change, and accordingly the detecting unit may erroneously detect the presence
of smoke even though no smoke is present in the detection space.
[0015] On the other hand, the smoke sensor 100 according to the first embodiment includes
the suppressor 5 disposed at the peripheral edge of the end of the detection cover
21, and furthermore, the suppressor 5 is at least partially in contact with the board
41. For this reason, the suppressor 5 can reduce the chance that the foreign matter
enters the detection space Sp1 through the gap between the detection cover 21 and
the board 41. Accordingly, in the first embodiment, there is an advantage that the
smoke sensor 100 can contribute to reducing the chance of the false detection due
to the foreign matter.
(1-2) Detailed Configuration
(1-2-1) Whole Configuration
[0016] Hereinafter, a detailed configuration of the smoke sensor 100 according to the first
embodiment will be described with reference to FIGS. 1 to 5.
[0017] As one example, the smoke sensor 100 is assumed to be mounted on a ceiling surface
A1 of the facility (refer to FIG. 2). Hereinafter, while the smoke sensor 100 is mounted
on the ceiling surface A1, directions perpendicular to (orthogonal to) the ceiling
surface A1 will be described as "up-down directions," a direction from the smoke sensor
100 toward the ceiling surface A1 will be described as an "upward direction," and
the opposite direction will be described as a "downward direction." The "Up" and "Dwn."
arrows in the drawings are shown for illustrative purposes only and are not tangible.
These directions are not intended to limit the direction of use (mounting direction)
of the smoke sensor 100.
[0018] As shown in FIGS. 1 and 3, the smoke sensor 100 includes a housing 1, a detection
block 2, a partition 3, a circuit block 4, a suppressor 5, a plurality (three in this
embodiment) of first screws 91, a second screw 92, an insect net 93, and a sound output
unit 94. In the first embodiment, the smoke sensor 100 further includes a battery
B1. The battery B1 is not an essential element in the smoke sensor 100. The battery
B1 may be omitted from the elements of the smoke sensor 100. In case that the battery
B1 is not provided in the smoke sensor 100, the smoke sensor 100 may receive power
supplied from an external power supply installed in the facility.
(1-2-2) Housing
[0019] The housing 1 houses therein the detection block 2, the circuit block 4, the suppressor
5, the insect net 93, and the sound output unit 94. The housing 1 is disk-shaped with
a circular shape in planar view. The housing 1 is a molded product made of synthetic
resin.
[0020] As shown in FIG. 1, the housing 1 includes a main body 10, a first cover 11, and
a second cover 12. The housing 1 is configured by combining the first cover 11 and
the second cover 12 with the main body 10. The housing 1 is fixed to a construction
surface (in this embodiment, the ceiling surface A1 (refer to FIG. 2)). More specifically,
the housing 1 is not fixed directly to the construction surface, but is fixed indirectly
to the construction surface by being attached to an attachment base (not shown) fixed
to the construction surface.
[0021] As shown in FIGS. 3 and 4, the main body 10 has a cylindrical shape. The partition
3 is provided on an inner surface of the main body 10. The main body 10 includes:
a first wall projecting from a peripheral edge of an upper surface of the partition
3 so as to extend a diameter of the first wall upwardly; and a second wall projecting
from a peripheral edge of a lower surface of the partition 3 to extend a diameter
of the second wall downwardly. The main body 10 includes a plurality of openings 101
arranged in a circumferential direction of the main body 10. Each of the plurality
of openings 101 has a rectangular shape long in the circumferential direction of the
main body 10 and penetrates the main body 10 in a thickness direction (i.e., a radial
direction) of the main body 10. Each of the plurality of openings 101 connects the
inside of the housing 1 to the outside of the housing 1. Therefore, smoke can flow
into the inside of the housing 1 from the outside of the housing 1 through any of
the plurality of openings 101. In the first embodiment, the plurality of openings
101 are disposed above the partition 3 in the main body 10, as shown in FIG. 2.
[0022] The partition 3 partitions the inside of the housing 1 in the up-down directions.
More specifically, as shown in FIG. 2, the partition 3 divides the inside of the housing
1 into: a first space interposed between the first cover 11 and the partition 3; and
a second space interposed between the second cover 12 and the partition 3 in the up-down
directions. As shown in FIGS. 3 and 4, the partition 3 includes a body portion 30
that has a first through hole 31, a second through hole 32, a plurality (three in
this embodiment) of first insertion holes 33, a second insertion hole 34, and a protrusion
35. The body portion 30 is a disk-shaped member.
[0023] The first through hole 31 penetrates the body portion 30 in the thickness direction
(the up-down directions) and has a generally circular shape similar to an outer shape
of a detection cover 21 (described later) of the detection block 2 in planar view.
The detection cover 21 of the detection block 2 is inserted into the first through
hole 31 from below. The second through hole 32 penetrates the body portion 30 in the
thickness direction (the up-down directions) and has a generally circular shape similar
to an outer shape of a battery case 114 (described later) of the first cover 11 in
planar view. The battery case 114 of the first cover 11 is inserted into the second
through hole 32 from below.
[0024] The plurality of first insertion holes 33 and the second insertion hole 34 penetrate
the body portion 30 in the thickness direction (the up-down directions) and have circular
shapes in planar view. Each of the plurality of first insertion holes 33 faces a corresponding
first boss 111 (described later) of the first cover 11 and a corresponding screw hole
121 (described later) of the second cover 12, while the first cover 11 and the second
cover 12 are combined with the main body 10. On the other hand, the second insertion
hole 34 faces a second boss 112 (described later) of the first cover 11 and a through
hole 42 (described later) of the board 41, while the first cover 11 and the second
cover 12 are combined with the main body 10.
[0025] As shown in FIG. 4, the protrusion 35 protrudes downward from a lower surface of
the body portion 30. The protrusion 35 is provided along a peripheral edge of the
first through hole 31. As one example, the dimension of the protrusion 35 in the up-down
directions is 1.2 mm. The dimension of the protrusion 35 in the up-down directions
is not required to be exactly 1.2 mm, and an error of ± 0.05 mm may be allowed.
[0026] As shown in FIG. 3, the first cover 11 has a disk shape that is circular in planar
view, and has an outer circumferential shape similar to that of the main body 10 in
planar view. The first cover 11 includes a plurality (three in this embodiment) of
first bosses 111, a second boss 112, an acoustic case 113, and a battery case 114.
The board 41 is disposed in a region surrounded by the plurality of first bosses 111
and the second boss 112, of the first cover 11.
[0027] Each of the plurality of first bosses 111 has a cylinder, and is provided integrally
with the first cover 11 so as to project upwardly from an upper surface of the first
cover 11. Each of the plurality of first bosses 111 has a screw hole into which a
corresponding first screw 91 of the three first screws 91 is screwed. The second boss
112 has a tubular body that is circular in planar view and is provided integrally
with the first cover 11 so as to project upwardly from the upper surface of the first
cover 11. The second boss 112 has a screw hole into which the second screw 92 is screwed.
[0028] The acoustic case 113 has a cylindrical body, and is provided integrally with the
first cover 11 so as to project upwardly from the upper surface of the first cover
11. The sound output unit 94 is housed in the acoustic case 113. The acoustic case
113 has a sound hole that is disposed in a bottom surface of the acoustic case 113
and penetrates the first cover 11 in the thickness direction (the up-down directions).
The sound output unit 94 outputs a sound to the outside through the sound hole. The
sound hole is covered with a decorative plate disposed on a lower surface of the first
cover 11.
[0029] The battery case 114 has a rectangular body-shaped box, and is provided integrally
with the first cover 11 so as to project upwardly from the upper surface of the first
cover 11. The battery case 114 houses therein the battery B1 that functions as a power
source for operation of the smoke sensor 100. The battery B1 may be a primary battery
or a secondary battery.
[0030] The second cover 12 has a disk-like shape that is circular in planar view, and has
an outer circumferential shape similar to that of the main body 10 in planar view.
The second cover 12 has a plurality (three in this embodiment) of screw holes 121.
Each of the plurality of screw holes 121 has a circular shape in planar view and penetrates
the second cover 12 in the thickness direction (the up-down directions). Into each
of the plurality of screw holes 121, a corresponding first screw 91 of the three first
screws 91 is inserted from above the second cover 12.
[0031] The housing 1 is assembled as follows. First, the first cover 11 is combined with
the main body 10 so as to close the upper opening in the main body 10. The second
cover 12 is then combined with the main body 10 so as to close the lower opening in
the main body 10. The plurality of first insertion holes 33 of the partition 3, the
plurality of first bosses 111 of the first cover 11, and the plurality of screw holes
121 of the second cover 12 are then superimposed on each other. In this state, each
of the plurality of first screws 91 is inserted and fastened into a corresponding
screw hole 121 from above the second cover 12, thereby the main body 10, the first
cover 11, and the second cover 12 being coupled to one another.
(1-2-3) Detection block
[0032] The detection block 2 includes a detecting unit 20 and a detection cover 21 as shown
in FIG. 3.
[0033] The detection cover 21 houses therein the detecting unit 20. The detection cover
21 has a tubular shape with bottom, and includes a bottom wall 211 and a peripheral
wall 212. The bottom wall 211 is a plate member that has a generally circular shape
in planar view. That is to say, the detection cover 21 has a cylindrical shape with
bottom. The peripheral wall 212 is provided to project downwardly from a peripheral
edge of the bottom wall 211.
[0034] As shown in FIG. 2, the detection space Sp1 is a space formed by the board 41 and
the detection cover 21 in the inside of the housing 1. In other words, the detection
space Sp1 is a space surrounded by the board 41 and the detection cover 21 in the
inside of the housing 1.
[0035] The detecting unit 20 is configured to detect the smoke in the detection space Sp1.
The detecting unit 20 includes a light emitting part 201 and a light receiving part
202, and is photoelectric. The "photoelectric" mentioned in this disclosure means
a method of sensing the smoke based on a change in the amount of light reflected by
the smoke particles in the detection space Sp1, or the amount of light transmitted
through the detection space Sp1, using the light emitting part 201 and the light receiving
part 202. In the first embodiment, the light emitting part 201 emits light toward
the detection space Sp1. The light receiving part 202 is disposed at a position not
to receive direct light from the light emitting part 201 but to receive scattered
light by the smoke particles in the detection space Sp1. Thus, in a state in which
no smoke is present in the detection space Sp1, the light receiving part 202 does
not receive the light emitted from the light emitting part 201, but in a state in
which the smoke is present in the detection space Sp1, the light receiving part 202
can receive light (i.e., scattered light) emitted from the light emitting part 201
and scattered by the smoke particles. Accordingly, the smoke sensor 100 can sense
the smoke being present in the detection space Sp1 in response to the state of light
reception of the light receiving part 202. The amount of light received by the light
receiving part 202 may change depending on, for example, a concentration of the smoke
in the detection space Sp1 or a type of the smoke (white smoke, black smoke, or any
other smoke). The light receiving part 202 outputs, to the circuit block 4, an output
signal corresponding to the amount of light received.
[0036] As shown in FIG. 2, the smoke sensor 100 further includes a flange 22 projecting
from a peripheral edge of an end of the detection cover 21. The flange 22 is disposed
between the partition 3 and the board 41 in a thickness direction D1 (up-down directions)
of the board 41. More specifically, as shown in FIG. 5, the smoke sensor 100 further
includes the flange 22 projecting from the peripheral edge of the end of the detection
cover 21 between the protrusion 35 of the partition 3 and the board 41 in the thickness
direction D1 of the board 41. In other words, the smoke sensor 100 further includes
the flange 22 projecting from the peripheral edge of the end of the detection cover
21 so as to be positioned between the protrusion 35 of the partition 3 and the board
41 in the thickness direction D1 of the board 41. FIG. 5 is an enlarged view of a
part of a cross-section shown in FIG. 2. The "end of the detection cover 21" mentioned
herein is an end, which is not connected to the bottom wall 211, of both ends of the
peripheral wall 212 in the up-down directions (i.e., a lower end of the peripheral
wall 212). The flange 22 is provided along the entire peripheral edge of the lower
end of the peripheral wall 212. That is to say, the flange 22 has a generally circular
ring shape in planar view. In the first embodiment, the cross-section of the flange
22 taken along the up-down directions has a rectangular shape. The flange 22 according
to the first embodiment is disposed to project outward from the peripheral edge of
the end of the detection cover 21. Specifically, the flange 22 according to the first
embodiment is disposed to project outward from a peripheral edge of a lower end of
the peripheral wall 212 of the detection cover 21. The "projecting outward" mentioned
herein means projecting, in the thickness direction (radial direction) of the peripheral
wall 212, toward a direction away from the bottom wall 211 (i.e., toward a direction
closer to the main body 10 (refer to FIG. 2)). That is to say, in the first embodiment,
the flange 22 and the bottom wall 211 are disposed not to overlap with each other
in planar view. In other words, the flange 22 is disposed not to fit within a projection
plane of the bottom wall 211 in the up-down directions. According to this configuration,
the smoke sensor 100 has an advantage that the partition 3 can more stably hold the
flange 22.
[0037] As shown in FIG. 5, the flange 22 has a first surface 221 and a second surface 222,
which face each other along the thickness direction D1 of the board 41. In the first
embodiment, the first surface 221 is a lower surface of the flange 22, and the second
surface 222 is an upper surface of the flange 22. The first surface 221 is in contact
with the board 41. More specifically, the first surface 221 is certainly in contact
with the upper surface of the board 41 so as to press against the upper surface by
a sufficient force. On the other hand, the second surface 222 is in contact with the
partition 3. More specifically, the lower surface of the protrusion 35 of the partition
3 is certainly in contact with the second surface 222 so as to press against the second
surface 222 by a sufficient force.
[0038] As shown in FIG. 3, the detection cover 21 includes a plurality of window holes 213
disposed in the peripheral wall 212, through which the smoke flows into the detection
cover 21 (i.e., the detection space Sp1). Accordingly, the smoke is allowed to flow
into the detection space Sp1 from the outside of the detection cover 21 through any
of the plurality of window holes 213. Each of the plurality of window holes 213 has
a rectangular shape in front view and penetrates the peripheral wall 212 in the thickness
direction (i.e., the radial direction) thereof.
[0039] The detection cover 21 further includes a plurality of insect nets 93 covering the
plurality of window holes 213, as shown in FIGS. 2 and 3. Each of the plurality of
insect nets 93 has a rectangular shape in front view. The plurality of insect nets
93 are attached to the peripheral wall 212 to cover the plurality of window holes
213 within the detection cover 21. In this embodiment, all of the plurality of window
holes 213 are covered with the plurality (two in this embodiment) of insect nets 93.
Each insect net 93 has a number of rectangular meshes, as shown in FIG. 3.
[0040] In the first embodiment, the detection block 2 further includes a labyrinth structure
23 that is disposed inside the detection cover 21, as shown in FIG. 2. The labyrinth
structure 23 is implemented as an aggregate of a plurality of small pieces circularly
arranged in the detection cover 21 to surround the detection space Sp1 in the circumferential
direction of the detection cover 21. The labyrinth structure 23 allows the smoke to
enter the detection space Sp1 through gaps between the plurality of small pieces from
the outside of the detection cover 21 and to be entrapped in the detection space Sp1.
The labyrinth structure 23, as shown in FIG. 5, has insertion portions 231 which are
respectively inserted into insertion holes 411 provided in the board 41. The labyrinth
structure 23 is fixed to the board 41 by the insertion portions 231 being inserted
into the insertion holes 411.
(1-2-4) Circuit Block
[0041] The circuit block 4 includes the board 41 and a plurality of electronic components
including a switch(es). The plurality of electronic components are mounted on the
board 41. The board 41 is, for example, a printed wiring board including a patterned
conductor. The detecting unit 20 of the detection block 2 is electrically connected
to the patterned conductor of the board 41. The sound output unit 94 and the battery
B1 are also electrically connected to the patterned conductor of the board 41.
[0042] The board 41 is disposed below the detection block 2 (i.e., between the detection
block 2 and the first cover 11), as shown in FIG. 2. The detection block 2 is disposed
on one surface (upper surface) of both surfaces in the thickness direction D1, of
the board 41. That is to say, the detecting unit 20 and the detection cover 21 are
disposed on the one surface in the thickness direction D1, of the board 41. In other
words, the detecting unit 20 and the detection cover 21 are mounted on the one surface
in the thickness direction D1, of the board 41.
[0043] As shown in FIG. 3, the board 41 has a through hole 42. The through hole 42 penetrates
the board 41 in the thickness direction (up-down directions) and has a circular shape
in planar view. The upper end of the second boss 112 of the first cover 11 is inserted
into the through hole 42. In this state, the second insertion hole 34 of the partition
3 and the second boss 112 of the first cover 11 are superimposed on each other, and
the second screw 92 is inserted and fastened into the second insertion hole 34 from
above, thereby the board 41 being held between the partition 3 and the first cover
11. More specifically, the board 41 is held between the partition 3 and the first
cover 11 in a state where the flange 22 provided to the detection cover 21 is disposed
between the board 41 and the partition 3. As a result, the partition 3 holds the flange
22 to press the flange 22 against the board 41.
[0044] The circuit block 4 further includes an antenna 43. While the shaft part of the second
screw 92 is inserted into one end of the antenna 43, the second screw 92 is inserted
and fastened in the through hole 42 of the first embodiment from above with the upper
end of the second boss 112 of the first cover 11 being inserted in the through hole
42. Thus, the antenna 43 is fixed to the board 41 in electrical connection to the
patterned conductor of the board 41. The antenna 43 is a part of a communication module
mounted on the board 41. The communication module is configured to communicate wirelessly
with another device (e.g., another smoke sensor, etc.).
[0045] The circuit block 4 includes a control circuit constituted by the plurality of electronic
components. The control circuit is configured to control the light emitting part 201,
the light receiving part 202, the sound output unit 94, and any other units. The control
circuit at least drives the light emitting part 201 and performs signal processing
on the output signal of the light receiving part 202. In the signal processing, the
circuit block 4 compares the amount of light received by the light receiving part
202 (e.g., the magnitude of the output signal) with a threshold value to determine
whether or not smoke is present in the detection space Sp1. When finding that the
amount of light received by the light receiving part 202 is equal to or more than
the threshold value, the circuit block 4 determines that smoke with a concentration
equal to or more than a certain level is present in the detection space Sp1. The circuit
block 4 outputs, to the sound output unit 94, an electrical signal for driving the
sound output unit 94 in response to the determination that the smoke with the concentration
equal to or more than the certain level is present in the detection space Sp1.
[0046] The sound output unit 94 is configured to output a sound (sound wave) in response
to reception of the electrical signal from the circuit block 4. That is to say, the
smoke sensor 100 makes the sound output unit 94 output the sound, when finding that
the amount of light received by the light receiving part 202 is equal to or more than
the threshold value. The sound output unit 94 is implemented as a speaker, a buzzer,
or the like, which converts an electrical signal to the sound. The sound output unit
94 is generally disk-shaped with a circular shape in planar view.
(1-3) Advantages
[0047] The flange 22 according to the first embodiment projects from the peripheral edge
of the lower end of the peripheral wall 212 of the detection cover 21, and is disposed
between the protrusion 35 of the partition 3 and the board 41 in the thickness direction
D1 (the up-down directions) of the board 41. In addition, the first surface 221 of
the flange 22 is in contact with the board 41, and the second surface 222 is in contact
with the partition 3.
[0048] According to this configuration, the flange 22 is pressed against the board 41 by
the partition 3, and can suppress generation of a gap between the protrusion 35 of
the detection cover 21 and the board 41. As a result, the flange 22 can prevent the
foreign matter from entering the detection space Sp1 from the gap between the detection
cover 21 and the board 41. That is to say, the suppressor 5 according to the first
embodiment includes the flange 22. More specifically, the suppressor 5 according to
the first embodiment is implemented as the flange 22. According to this configuration,
the smoke sensor 100 can reduce the chance that the foreign matter enters the detection
space Sp1 from the outside without the smoke sensor 100 having the complicated internal
structure. Accordingly, the smoke sensor 100 can contribute to reducing the chance
of the false detection due to the foreign matter without the smoke sensor 100 having
the complicated internal structure.
[0049] Furthermore, as shown in FIG. 4, the protrusion 35 is disposed to protrude downward
from the lower surface of the main body 10.
[0050] According to this configuration, the partition 3 can more strongly press the flange
22 provided to the detection cover 21 against the board 41. For this reason, the flange
22 can prevent the gap from being generated between the detection cover 21 and the
board 41. The occurrence of intervals can be more inhibited. As a result, the flange
22 can further reduce the chance that the foreign matter enters the detection space
Sp1 from the gap between the detection cover 21 and the board 41. Accordingly, the
smoke sensor 100 can contribute to further reducing the chance of the false detection
due to the foreign matter.
(1-4) Variations of First Embodiment
[0051] The first embodiment described above is merely one of various exemplary embodiments
of the present disclosure. The first embodiment described above may be readily modified
in various manners depending on the design or any other factor, as long as the purpose
of the present disclosure can be achieved. Each of the following variations may be
implemented in combination with the other variation as appropriate.
(1-4-1) First Variation
[0052] FIG. 6 shows a schematic cross-sectional view of an essential part of a smoke sensor
100a according to the first variation.
[0053] Similarly to the smoke sensor 100, the smoke sensor 100a includes a flange 22a that
projects from a peripheral edge of a lower end of a peripheral wall 212 of a detection
cover 21 and is disposed between a protrusion 35 of a partition 3 and a board 41 in
a thickness direction D1 (up-down directions) of the board 41. The flange 22a projects
outward to be curved downwardly from the peripheral edge of the lower end of the peripheral
wall 212. The "outward" mentioned herein is a direction away from a bottom wall 211
in the thickness direction (radial direction) of the peripheral wall 212. The flange
22a has a first end 223a and a second end 224a as a pair of ends facing each other
along the projecting direction of the flange 22a. The flange 22a projects outward
while being curved downwardly such that the second end 224a is closer to the board
41 than the first end 223a is (in other words, the second end 224a is positioned below
the first end 223a). The "first end 223a" mentioned herein is one end, which is connected
to the lower end of the peripheral wall 212 of the detection cover 21, of the paired
ends facing each other along the projecting direction. The "second end 224a" mentioned
herein is the other end, which is different from the first end 223a, of the paired
ends facing each other along the projecting direction. That is to say, the "second
end 224a" is a tip end of the flange 22a.
[0054] The flange 22a has a first surface 221a and a second surface 222a facing each other
along the thickness direction D1 of the board 41. In the first variation, since the
flange 22a is provided to be curved, the first surface 221a is partially in contact
with the board 41. More specifically, as shown in FIG. 6, the first surface 221a includes
a first region on the side of the first end 223a and a second region on the second
end 224a, and the first region is separated from the board 41, but the second region
is in contact with the board 41 so as to press against the board 41 by a sufficient
force. On the other hand, the second surface 222a is in contact with the partition
3. In other words, the lower surface of the protrusion 35 of the partition 3 is in
contact with a certain region of the second surface 222a on the side of the second
end 224a so as to press against the certain region by a sufficient force.
[0055] Since the detection cover 21 is mounted to the board 41 while being pressed downwardly,
the flange 22a curved is deflected. As a result, the flange 22a has an elastic force
to press at least a part of the first surface 221a against the board 41. More specifically,
the flange 22a has an elastic force to press the second region on the side of the
second end 224a, of the first surface 221a, against the board 41. According to this
configuration, the flange 22a is pressed against the board 41 by the partition 3,
and furthermore, the flange 22a can be more certainly in contact with the board 41
by the elastic force (in other words, the adhesion between the flange 22a and the
board 41 can be improved), which can further reduce the chance that the foreign matter
enters the detection space Sp1 from the outside. Therefore, the smoke sensor 100a
can contribute to further reducing the chance of the false detection due to the foreign
matter.
(1-4-2) Second Variation
[0056] FIG. 7A shows a schematic cross-sectional view of an essential part of a smoke sensor
100b according to the second variation.
[0057] Similarly to the smoke sensor 100, the smoke sensor 100b includes a flange 22b that
projects from a peripheral edge of a lower end of a peripheral wall 212 of a detection
cover 21 and is disposed between a protrusion 35 of a partition 3 and a board 41 in
a thickness direction D1 (up-down directions) of the board 41. The flange 22b has
a generally circular ring shape in planar view and has a first surface 221b and a
second surface 222, which face each other along the thickness direction D1 of the
board 41.
[0058] The flange 22b of the smoke sensor 100b includes an uneven part 24 provided in the
whole of the first surface 221b. For example, the uneven part 24 includes a plurality
of annular-shaped protrusions 241 that protrude downward from the first surface 221b
and are provided with approximately equal intervals along a radial direction of the
flange 22b. The cross-section of each of the plurality of protrusions 241, taken along
the up-down directions, has an inverted triangular shape. Alternatively, the uneven
part 24 may include a plurality of conical-shaped protrusions that protrude downward
from the first surface 221b and are provided with approximately equal intervals along
the circumferential direction and the radial direction of the flange 22b.
[0059] According to this configuration, the plurality of protrusions 241 of the uneven part
24 of the first surface 221b are crushed against the board 41, and therefore, the
flange 22b can be more certainly in contact with the board 41 (in other words, the
adhesion between the flange 22b and the board 41 can be improved). For this reason,
the flange 22b can further reduce the chance that the foreign matter enters the detection
space Sp1 from the outside. Accordingly, the smoke sensor 100b can contribute to further
reducing the chance of the false detection due to the foreign matter. Also, according
to this configuration, the external force applied from the flange 22b to the board
41 can be dispersed, and therefore, the smoke sensor 100b can buffer the stress generated
at the board 41.
[0060] The uneven part 24 is disposed in the whole of the first surface 221b of the flange
22b but may be disposed in a part of the first surface 221b. That is to say, the uneven
part 24 may be disposed in at least a part of the first surface 221b.
[0061] Alternatively, as with a smoke sensor 100c shown in FIG. 7B, an uneven part 24 may
be disposed in a second surface 222c of a flange 22c. According to this configuration,
in the smoke sensor 100c, the external force applied from a protrusion 35 of a partition
3 to the flange 22c can be dispersed, so that the external force applied from the
flange 22c to a board 41 can be also dispersed. As a result, the smoke sensor 100c
can buffer the stress generated at the board 41.
(1-4-3) Third Variation
[0062] FIG. 8A shows a schematic cross-sectional view of an essential part of a smoke sensor
100d according to the third variation.
[0063] Similarly to the smoke sensor 100, the smoke sensor 100d includes a flange 22d that
projects from a peripheral edge of a lower end of a peripheral wall 212 of a detection
cover 21 and is disposed between a protrusion 35 of a partition 3 and a board 41 in
a thickness direction D1 (up-down directions) of the board 41. The flange 22d has
a generally circular ring shape in planar view and has a first surface 221 and a second
surface 222d, which face each other along the thickness direction D1 of the board
41.
[0064] The smoke sensor 100d includes a resin part 61 as a buffer member 6. The resin part
61 is disposed between a second surface 222d of the flange 22d and the partition 3.
The partition 3 is disposed to indirectly press the flange 22d against the board 41
through the buffer member 6 (resin part 61). That is to say, the second surface 222d
of the flange 22d is not in directly contact with the partition 3, but in indirectly
contact with the partition 3 through the buffer member 6. According to this configuration,
the buffer member 6 can buffer an external force applied from the partition 3 to the
flange 22d, and can also therefore buffer an external force applied from the flange
22d to the board 41. As a result, the smoke sensor 100d can also contribute to reducing
the stress generated at the board 41.
[0065] The resin part 61 may be made of, for example, silicone or urethane. Alternatively,
the resin part 61 may be made of photo-curable resin such as UV photon resin. Note
that, the material of the resin part 61 is not limited in particular, as long as the
resin part 61 can be disposed between the second surface 222d of the flange 22d and
the partition 3.
[0066] In order to realize that the resin part 61 is more certainly in contact with the
flange 22d while pressing against the flange 22d by a sufficient force (in other words,
in order to improve the adhesion between the flange 22d and the resin part 61), the
second surface 222d of the flange 22d, which is in contact with the resin part 61,
is a rough surface. The "rough surface" mentioned herein may be, for example, a surface
in which irregularities are provided, or a surface of which surface state is changed
by plasma treatment or any other treatment. According to this configuration, providing
the rough surface can increase the surface area of the flange 22d which is in contact
with the resin part 61, and the flange 22d can therefore obtain a physical adhesive
effect. That is to say, the smoke sensor 100d can also contribute to improving the
adhesion between the flange 22d and the resin part 61.
[0067] As shown in FIG. 7B, a smoke sensor 100e may include a packing member 62 as the buffer
member 6. For example, the packing member 62 is made of a rubber material such as
a fluorine rubber or a silicone rubber. Note that, the material of the packing member
62 is not limited in particular, as long as the packing member 62 can close the gap
between the second surface 222d of the flange 22d and the partition 3.
[0068] Similarly, as shown in FIG. 7C, a smoke sensor 100f may include a brush-shaped member
63 as the buffer member 6. The brush-shaped member 63 is implemented as an aggregate
of hairs growing upwardly from the second surface 222d of the flange 22d. For example,
the brush-shaped member 63 is made of synthetic fibers such as polypropylene or nylon.
Alternatively, the brush-shaped member 63 may be made of vegetable fibers, animal
fibers, or metal fibers. Note that, the material of the brush-shaped member 63 is
not limited in particular, as long as the brush-shaped member 63 can close the gap
between the second surface 222d of the flange 22d and the partition 3.
(1-4-4) Other Variations
[0069] Hereinafter, other variations according to the first embodiment described above are
listed.
[0070] In the first embodiment described above, the flange 22 is disposed to project outward
from the peripheral edge of the lower end of the peripheral wall 212 of the detection
cover 21, but may be disposed to project inward. The "projecting inward" mentioned
herein means projecting toward a direction away from the main body 10 in the thickness
direction (the radial direction) of the peripheral wall 212. That is to say, the flange
22 and the bottom wall 211 may be disposed so as to overlap with each other in planar
view. In other words, the flange 22 may be disposed to be within a projection plane
of the bottom wall 211 in the up-down directions.
[0071] The main body 10 according to the first embodiment described above includes the plurality
of openings 101 arranged in the circumferential direction, but should not be construed
as limiting. The main body 10 may include at least one opening 101. That is to say,
a single opening 101 may be provided in the main body 10 to be arranged in the circumferential
direction.
[0072] The partition 3 according to the first embodiment described above includes the protrusion
35, but may not include the protrusion 35.
[0073] In the first embodiment described above, the bottom wall 211 of the detection cover
21 is a plate member that has a generally circular shape in planar view, but may be
a plate member that has a polygonal shape in planar view. That is to say, the detection
cover 21 may have a tubular shape with bottom, which is polygonal-shaped in planar
view.
[0074] The detection cover 21 according to the first embodiment described above includes
the plurality of window holes 213 in the peripheral wall 212, but should not be construed
as limiting. The detection cover 21 may include at least one window hole 213. That
is to say, the detection cover 21 may include a single window hole 213 disposed in
the peripheral wall 212.
(2) Second Embodiment
(2-1) Overview
[0075] Hereinafter, a smoke sensor 100g according to the second embodiment will be described
with reference to FIG. 9A. In the second embodiment, elements similar to those of
the first embodiment are assigned with same reference signs, and the explanations
thereof are appropriately omitted.
[0076] The smoke sensor 100g according to the second embodiment is different from the smoke
sensor 100 according to the first embodiment in that the smoke sensor 100g includes
a resin part 7. In addition, the smoke sensor 100g according to the second embodiment
is different from the smoke sensor 100 according to the first embodiment in that a
suppressor 5a of the smoke sensor 100g includes a flange 22g and the resin part 7.
(2-2) Detailed Configuration
[0077] In the second embodiment, the smoke sensor 100g includes the flange 22g provided
to a detection cover 21, similarly to that of the first embodiment. The flange 22g
projects outward from the whole of the peripheral edge of the end of the detection
cover 21. As shown in FIG. 9A, the flange 22g has a first surface 221g and a second
surface 222, which face along a thickness direction D1 of a board 41. The first surface
221g is a lower surface of the flange 22g and the second surface 222 is an upper surface
of the flange 22g. The first surface 221g according to the second embodiment is different
from the first surface 221 according to the first embodiment in that the first surface
221g is not in contact with the board 41. More specifically, in the second embodiment,
a space (gap) is provided between the first surface 221g of the flange 22g and an
upper surface of the board 41 in the thickness direction D1 of the board 41. On the
other hand, the second surface 222 according to the second embodiment is in contact
with the partition 3, similarly to the second surface 222 according to the first embodiment.
More specifically, a lower surface of a protrusion 35 of the partition 3 is certainly
in contact with the second surface 222 so as to press against the second surface 222
by a sufficient force.
[0078] The smoke sensor 100g according to the second embodiment includes the resin part
7. The resin part 7 is disposed to be in contact with both the flange 22g and the
board 41. More specifically, the resin part 7 is in contact with both an end surface
225g of the flange 22g and the upper surface of the board 41. The "end surface 225g
of the flange 22g" mentioned herein is an end surface, which is different from an
end surface connected to the detection cover 21 (peripheral wall 212), of paired end
surfaces facing each other along a projecting direction of the flange 22g. That is
to say, the "end surface 225g of the flange 22g" is a tip end surface of the flange
22g. In other words, the flange 22g and the resin part 7 are disposed to close the
gap between the detection cover 21 and the board 41.
[0079] According to the configuration described above, in the second embodiment, the flange
22g and the resin part 7 suppress a foreign matter from entering the detection space
Sp1 through the gap between the detection cover 21 and the board 41. That is to say,
the suppressor 5a according to the second embodiment includes the flange 22g and the
resin part 7. In other words, the suppressor 5a according to the second embodiment
further includes the resin part 7 in addition to the flange 22g. More specifically,
the suppressor 5a according to the second embodiment is configured by the flange 22g
and the resin part 7. According to this configuration, the smoke sensor 100g can further
suppress the chance that the gap is generated between the flange 22g and the board
41. As a result, the smoke sensor 100g has an effect of further suppressing the foreign
matter from entering the detection space Sp1 from the outside. Therefore, the smoke
sensor 100g can contribute to reducing a chance of a false detection due to the foreign
matter. Furthermore, the smoke sensor 100g has an advantage that the resin part 7
can buffer the external force applied to the board 41 from the flange 22g, and also
reduce the stress generated at the board 41.
[0080] The resin part 7 is made of, for example, silicone or urethane. Alternatively, the
resin part 7 may be made of photo-curable resin such as UV photon resin. Note that,
the material of the resin part 7 is not limited in particular, as long as the resin
part 7 can be disposed to be in contact with both the flange 22g and the board 41.
[0081] The end surface 222g of the flange 22g, which is a surface in contact with the resin
part 7, is a rough surface. The "rough surface" mentioned herein may be, for example,
a surface in which irregularities are provided, or a surface of which surface state
is changed by plasma treatment or any other treatment. According to this configuration,
providing the rough surface can increase the surface area of the end surface 222g
which is in contact with the resin part 7, and the flange 22g can therefore obtain
a physical adhesive effect. That is to say, the smoke sensor 100g can also contribute
to improving the adhesion between the flange 22g and the resin part 7.
(2-3) Variations of Second Embodiment
[0082] The second embodiment described above is merely one of various exemplary embodiments
of the present disclosure. The second embodiment described above may be readily modified
in various manners depending on the design or any other factor, as long as the purpose
of the present disclosure can be achieved. Each of the following variations may be
implemented in combination with the other variation as appropriate.
[0083] In the smoke sensor 100g according to the second embodiment described above, the
resin part 7 is disposed to be in contact with both the end surface 225g of the flange
22g and the upper surface of the board 41. However, as shown in FIG. 9B, a resin part
7a of a smoke sensor 100h may be disposed to be in contact with both a first surface
221h of a flange 22h and an upper surface of a board 41. That is to say, the position
of the resin part 7a is not limited in particular, as long as the flange 22h and the
resin part 7a are disposed to close the gap between the detection cover 21 and the
board 41. In the smoke sensor 100h, the first surface 221h is partially in contact
with the resin part 7a. Alternatively, the whole of the first surface 221h may be
in contact with the resin part 7a.
[0084] Furthermore, the first surface 221h of the flange 22h, which is a surface in contact
with the resin part 7a, is a rough surface. More specifically, the whole of the first
surface 221h of the flange 22h (including not only a region in contact with the resin
part 7a but also a region not in contact with the resin part 7a) is the rough surface.
Note that, at least a part, which is in contact with the resin part 7a, of the first
surface 221h may have the rough surface.
(3) Third Embodiment
(3-1) Overview
[0085] Hereinafter, a smoke sensor 100i according to the third embodiment will be described
with reference to FIG. 10A. In the third embodiment, elements similar to those of
the first embodiment are assigned with same reference signs, and the explanations
thereof are appropriately omitted.
[0086] The smoke sensor 100i according to the third embodiment is different from the smoke
sensor 100 according to the first embodiment in that the smoke sensor 100i includes
a blocking part 8. In addition, the smoke sensor 100i according to the third embodiment
is different from the smoke sensor 100 according to the first embodiment in that a
suppressor 5c of the smoke sensor 100i includes a flange 22i and the blocking part
8.
(3-2) Detailed Configuration
[0087] In the third embodiment, the smoke sensor 100i includes the flange 22i provided to
a detection cover 21, similarly to that of the first embodiment. The flange 22i projects
outward from the whole of the peripheral edge of the end of the detection cover 21.
As shown in FIG. 10A, the flange 22i has a first surface 221i and a second surface
222, which face along a thickness direction D1 of a board 41. The first surface 221i
is a lower surface of the flange 22i and the second surface 222 is an upper surface
of the flange 22i. The first surface 221i according to the third embodiment is different
from the first surface 221 according to the first embodiment in that the first surface
221i is not in contact with the board 41. More specifically, in the third embodiment,
a space (gap) is provided between the first surface 221i of the flange 22i and an
upper surface of the board 41 in the thickness direction D1 of the board 41. On the
other hand, the second surface 222 according to the third embodiment is in contact
with the partition 3, similarly to the second surface 222 according to the first embodiment.
More specifically, a lower surface of a protrusion 35 of the partition 3 is certainly
in contact with the second surface 222 so as to press against the second surface 222
by a sufficient force.
[0088] The smoke sensor 100i according to the third embodiment includes the blocking part
8. The blocking part 8 is disposed to close the gap between the flange 22i and the
board 41. More specifically, the blocking part 8 is disposed to close the gap between
the first surface 221i of the flange 22i and the upper surface of the board 41. The
blocking part 8 according to the third embodiment is a packing member 81 provided
on the first surface 221i of the flange 22i. Since the flange 22i has a generally
circular ring shape in planar view, the packing member 81 is also implemented as a
member with a generally circular ring shape in planar view. The cross-sectional shape
of the packing member 81 is a substantially inversely triangular shape, and the lower
end of the packing member 81 is crushed against the board 41, which can more tightly
close the gap between the flange 22i and the board 41. For example, the packing member
81 is made of a rubber material such as a fluorine rubber or a silicone rubber. Note
that, the material of the packing member 81 is not limited in particular, as long
as the packing member 81 can close the gap between the flange 22i and the board 41.
[0089] According to the configuration described above, in the third embodiment, the flange
22i and the blocking part 8 (packing member 81) suppress a foreign matter from entering
the detection space Sp1 from the gap between the detection cover 21 and the board
41. That is to say, the suppressor 5c according to the third embodiment includes the
flange 22i and the blocking part 8. In other words, the suppressor 5c according to
the third embodiment further includes the blocking part 8 in addition to the flange
22i. According to this configuration, the blocking part 8 can reduce an external force
applied to the board 41 from the flange 22i. Therefore, the smoke sensor 100i has
an effect of further suppressing the foreign matter from entering the detection space
Sp1 from the outside, while further reducing the stress generated at the board 41.
Therefore, the smoke sensor 100i can contribute to reducing a chance of a false detection
due to the foreign matter.
(3-3) Variation of Third Embodiment
[0090] The third embodiment described above is merely one of various exemplary embodiments
of the present disclosure. The third embodiment described above may be readily modified
in various manners depending on the design or any other factor, as long as the purpose
of the present disclosure can be achieved. Each of the following variations may be
implemented in combination with the other variation as appropriate.
[0091] The blocking part 8 according to the third embodiment is implemented as the packing
member 81, but may be implemented as a brush-shaped member 82, as shown in FIG. 10B.
The brush-shaped member 82 is disposed on a first surface 221j of a flange 22j. More
specifically, the brush-shaped member 82 is implemented as an aggregate of hairs growing
downwardly from the first surface 221j of the flange 22j. For example, the brush-shaped
member 82 is made of synthetic fibers such as polypropylene or nylon. Alternatively,
the brush-shaped member 82 may be made of vegetable fibers, animal fibers, or metal
fibers. Note that, the material of the brush-shaped member 82 is not limited in particular,
as long as the brush-shaped member 82 can close the gap between the flange 22j and
the board 41.
[0092] In the smoke sensor 100j shown in FIG. 10B, the flange 22j and the brush-shaped member
82 suppress the foreign matter from entering the detection space Sp1 from the outside.
That is to say, a suppressor 5d with the configuration shown in FIG. 10B includes
the flange 22j and the brush-shaped member 82. In other words, the suppressor 5d further
includes the brush-shaped member 82 in addition to the flange 22j.
[0093] Alternatively, the blocking part 8 may be implemented as an adhesive tape 83, as
shown in FIG. 10C. The adhesive tape 83 is attached to the upper surface of the board
41. More specifically, the adhesive tape 83 is attached to the upper surface of the
board 41 so as to have a generally circular ring shape in planar view. The adhesive
tape 83 and a flange 22k are disposed to overlap with each other in planar view. In
other words, the adhesive tape 83 is disposed to be within a projection plane of the
flange 22k in the up-down directions. The adhesive tape 83 has an upper surface with
adhesiveness. Therefore, the adhesive tape 83 can catch the foreign matter, which
passes through the gap between the flange 22k and the adhesive tape 83, on the upper
surface with adhesiveness.
[0094] In a smoke sensor 100k shown in FIG. 10C, the flange 22k and the adhesive tape 83
suppress the foreign matter from entering the detection space Sp1 from the gap between
the detection cover 21 and the board 41. That is to say, a suppressor 5e with the
configuration shown in FIG. 10C includes the flange 22k and the adhesive tape 83.
In other words, the suppressor 5e further includes the adhesive tape 83 in addition
to the flange 22k.
[0095] Thus, the blocking part 8 according to the third embodiment may include at least
one of the packing member 81, the brush-shaped member 82, and the adhesive tape 83.
According to this configuration, the blocking part 8 can reduce the external force
applied to the board 41 from the flange (22i-22k), and can also reduce the stress
generated at the board 41.
(Recapitulation)
[0096] A smoke sensor (100, 100a-100k) according to a first aspect includes a housing (1),
a detecting unit (20), a partition (3), a board (41), a detection cover (21) having
a tubular shape with bottom, and a suppressor (5, 5a-5e). The housing (1) has an opening
(101) through which smoke flows into the housing (1) from an outside of the housing
(1). The detecting unit (20) is configured to detect the smoke in a detection space
(Sp1) provided in an inside of the housing (1). The partition (3) is configured to
divide the inside of the housing (1). On the board (41), the detecting unit (20) is
disposed. The detection cover (21) is configured to house the detecting unit (20).
The suppressor (5, 5a-5e) is disposed at a peripheral edge of an end of the detection
cover (21), and configured to suppress a foreign matter from entering the detection
space (Sp1) from the outside. The detection space (Sp1) is a space formed by the board
(41) and the detection cover (21). The suppressor (5, 5a-5e) is disposed between the
board (41) and the partition (3). The suppressor (5, 5a-5e) is at least partially
in contact with the board (41).
[0097] According to this aspect, the smoke sensor (100, 100a-100k) can contribute to reducing
the chance of a false detection due to a foreign matter.
[0098] In a smoke sensor (100, 100a-100k) according to a second aspect, which may be implemented
in conjunction with the first aspect, the detection cover (21) includes: a window
hole (213) through which the smoke flows into the detection cover (21); and an insect
net (93) disposed to cover the window hole (213).
[0099] According to this aspect, the smoke sensor (100, 100a-100k) can contribute to sensing
the smoke more efficiently.
[0100] A smoke sensor (100, 100a-100k) according to a third aspect, which may be implemented
in conjunction with the first or second aspect, further includes a flange (22, 22a-22k).
The flange (22, 22a-22k) projects from the peripheral edge of the end of the detection
cover (21), the flange (22, 22a-22k) being disposed between the partition (3) and
the board (41) in a thickness direction (D1) of the board (41). The suppressor (5,
5a-5e) includes the flange (22, 22a-22k).
[0101] According to this aspect, the smoke sensor (100, 100a-100k) can contribute to reducing
the chance of the false detection due to the foreign matter.
[0102] In a smoke sensor (100, 100a-100k) according to a fourth aspect, which may be implemented
in conjunction with the third aspect, the flange (22, 22a-22k) is disposed to project
outward.
[0103] According to this aspect, the smoke sensor (100, 100a-100k) has the advantage that
the partition (3) can more stably hold the flange (22, 22a-22k).
[0104] In a smoke sensor (100, 100a-100f) according to a fifth aspect, which may be implemented
in conjunction with the third or fourth aspect, the flange (22, 22a-22f) has a first
surface (221, 221a, 221b) and a second surface (222), which face each other along
the thickness direction (D1). The first surface (221, 221a, 221b) is in contact with
the board (41).
[0105] According to this aspect, the smoke sensor (100, 100a-100f) can contribute to reducing
the chance of the false detection due to the foreign matter without the smoke sensor
(100, 100a-100f) having a complicated internal structure.
[0106] In a smoke sensor (100a) according to a sixth aspect, which may be implemented in
conjunction with the fifth aspect, the flange (22a) has an elastic force to press
at least a part of the first surface (221a) against the board (41).
[0107] According to this aspect, the flange (22a) can be more certainly in contact with
the board (41), and the smoke sensor (100a) can further reduce the chance of the false
detection due to the foreign matter.
[0108] In a smoke sensor (100b) according to a seventh aspect, which may be implemented
in conjunction with the fifth or sixth aspect, the first surface (221b) includes an
uneven part (24) that is disposed in at least a part of the first surface (221b).
[0109] According to this aspect, the flange (22b) can be more certainly in contact with
the board (41), and the smoke sensor (100b) can further reduce the chance of the false
detection due to the foreign matter. Furthermore, the smoke sensor (100b) can buffer
the stress generated at the board (41).
[0110] In a smoke sensor (100g, 100h) according to an eighth aspect, which may be implemented
in conjunction with the third or fourth aspect, the suppressor (5a, 5b) further includes
a resin part (7, 7a). The resin part (7, 7a) is disposed to be in contact with both
of the flange (22g, 22h) and the board (41).
[0111] According to this aspect, the smoke sensor (100g, 100h) can contribute to further
suppressing the foreign matter from entering the detection space (Sp1) from the outside.
Furthermore, the smoke sensor (100g, 100h) can buffer the stress generated at the
board (41).
[0112] In a smoke sensor (100g, 100h) according to a ninth aspect, which may be implemented
in conjunction with the eighth aspect, the flange (22g, 22h) has a rough surface,
as a surface that is in contact with the resin part (7, 7a).
[0113] According to this aspect, the smoke sensor (100g, 100h) has the advantage that the
flange (22g, 22h) can be more certainly in contact with the resin part (7, 7a).
[0114] In a smoke sensor (100i-100k) according to a tenth aspect, which may be implemented
in conjunction with the third or fourth aspect, the suppressor (5c-5e) further includes
a blocking part (8). The blocking part (8) is disposed to close a gap between the
flange (22i-22k) and the board (41). The blocking part (8) is disposed to be in contact
with the board (41).
[0115] According to this aspect, the smoke sensor (100i-100k) can contribute to further
suppressing the foreign matter from entering the detection space (Sp1) from the outside,
while reducing the stress generated at the board (41).
[0116] In a smoke sensor (100i-100k) according to an eleventh aspect, which may be implemented
in conjunction with the tenth aspect, the blocking part (8) includes at least one
of a packing member (81), a brush-shaped member (82) and an adhesive tape (83).
[0117] According to this aspect, the smoke sensor (100i-100k) can contribute to further
suppressing the foreign matter from entering the detection space (Sp1) from the outside,
while reducing the stress generated at the board (41).
Reference Signs List
[0118]
- 100, 100a-100k
- Smoke Sensor
- 1
- Housing
- 101
- Opening
- 20
- Detecting Unit
- 21
- Detection Cover
- 213
- Window Hole
- 22, 22a-22k
- Flange
- 221, 221a, 221b
- First Surface
- 222
- Second Surface
- 24
- Uneven Part
- 3
- Partition
- 41
- Board
- 5, 5a-5e
- Suppressor
- 7, 7a
- Resin Part
- 8
- Blocking Part
- 81
- Packing Member
- 82
- Brush-shaped Member
- 83
- Adhesive Tape
- 93
- Insect Net
- D1
- Thickness Direction
- Sp1
- Detection Space