JP2018067067A - Photoelectric smoke sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent steam, etc. which is not a sensing target from flowing into a smoke detection part provided on an upper side concerning a photoelectric smoke sensor having a smoke flow-in part under the smoke detection part.SOLUTION: A photoelectric smoke sensor 1 comprises a smoke flow-in part 3 under a smoke detection part 2. The smoke flow-in part 3 includes a flow-in space 3a that is formed between a pair of upper and lower plate-like parts 5a and 5b and is formed as an open space whose circumference is opened to an outside. The lower plate-like part 5b includes a projection 5d that is provided on a side of a surface 5j opposing to the upper plate-like part 5a and projecting upward so as to penetrate an opening 5e formed in the upper plate-like part 5a. In the upper plate-like part 5a, a communication port 5f for communication between the smoke detection part 2 and the smoke flow-in part 3 is formed in an annular shape inside the opening 5e.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a photoelectric smoke detector that optically detects smoke.

  The photoelectric smoke detector optically detects the smoke flowing in from the smoke inflow part when the light receiving element receives the scattered light generated in the smoke detection part as the light emitted from the light emitting element is scattered by the smoke particles. It is configured to detect.

  Conventionally, in such photoelectric smoke detectors, there is one in which a smoke inflow portion into which smoke flows from the outside is provided below the smoke detection portion. In this way, by arranging the smoke detector and smoke inlet in two stages, it separates the smoke with a small mass and the one that originates from a cause other than a fire, such as a steam with a large mass. This makes it easier for smoke to flow into the upper smoke detection section, while making it difficult for steam or the like not to be detected to flow into the upper smoke detection section (see, for example, Patent Document 1).

JP 2010-238109 A

  By the way, the photoelectric smoke detector has a labyrinth made up of a large number of light shielding walls that block external light from entering the smoke detection section while forming a smoke flow path in the smoke inflow section that guides smoke from the outside to the smoke detection section. The part is provided in the smoke inflow part. Even in the case where the smoke inflow portion is provided below the smoke detection portion, the labyrinth portion having such a complicated structure is provided in the smoke inflow portion (see Patent Document 1).

  However, if the labyrinth section as described above is provided, steam or the like that is not to be detected may stay in the labyrinth section, and the accumulated steam or the like rises and flows into the upper smoke detector section. May end up. That is, even in a photoelectric smoke detector in which a smoke inflow section is provided below the smoke detection section, steam or the like that is not a detection target may flow into the smoke detection section.

  In view of the above circumstances, in the photoelectric smoke detector in which a smoke inflow portion is provided below the smoke detection portion, the present invention prevents steam that is not a detection target from flowing into the smoke detection portion above. Objective.

  The present invention relates to a photoelectric smoke detector in which a smoke inflow portion is provided below a smoke detection portion, wherein the smoke inflow portion is an inflow space formed between a pair of upper and lower plate-shaped portions, Is formed as an open space that is open to the outside, and has an inflow space that allows airflow flowing in from one side of the periphery to pass through the inside in a straight line in the horizontal direction and flow out from the other side. The lower plate-like portion of the pair of upper and lower plate-like portions protrudes upward on the surface facing the upper plate-like portion and is formed on the upper plate-like portion. A projecting portion penetrating through the opening facing the smoke detecting section is provided, and the upper plate-like portion of the pair of upper and lower plate-like portions has an opening in the opening. By connecting the smoke inflow part and the smoke detection part, the projecting part penetrates the part. Mouth a photoelectric smoke sensor, characterized in that it is formed as an annular.

  In the present invention, terms indicating the positional relationship such as “upper” and “lower” are used in accordance with the positional relationship when the photoelectric smoke detector is attached to the ceiling.

  Further, the present invention is the photoelectric smoke detector characterized in that the opening is provided with an inclined step portion inclined downward inward at the mouth edge thereof.

  In the present invention, the upper plate-like portion is provided with a plurality of ridges extending radially around the opening on the surface facing the lower plate-like portion. This is a photoelectric smoke detector characterized by the following.

  Further, according to the present invention, the upper plate-like portion is provided with a smoke detection section cover that covers the smoke detection section from below on the surface facing the smoke detection section. It is a smoke detector.

  In the present invention, smoke and steam flowing into the inflow space portion that do not hit the projecting portion flow in the lateral direction as it is and flow out to the outside. On the other hand, in the case of the projecting portion, smoke and steam are shunted up and down due to the difference in mass. That is, since smoke is light, it rises and is shunted upward, and steam and the like are heavy and are shunted downward without rising due to inertia. And since the smoke divided | segmented upward is light, it is induced | guided | derived upwards by the protrusion part, flows further upwards, passes through the cyclic | annular communication port formed around a protrusion part, and flows in into a smoke detection part. On the other hand, the steam or the like that is diverted downward is heavy, so that it flows downward without being guided upward due to inertia, flows laterally inside the smoke detector, and flows out to the outside.

  In other words, according to the present invention, of the smoke and steam flowing into the inflow space portion, the smoke that is the detection target hits the projecting portion, so that the smoke that is not the detection target is allowed to flow into the smoke detection section. Of course, not only those that do not hit the protruding portion but also those that hit the protruding portion can flow out to the outside without staying inside the inflow space portion.

  Therefore, according to the present invention, in the photoelectric smoke detector in which the smoke inflow section is provided in the lower part of the smoke detection section, the smoke to be detected flows into the upper smoke detection section but is not the detection target. Steam or the like can be prevented from flowing into the upper smoke detector.

  Moreover, according to this invention, the inclination step part which inclines below toward the center is provided in the lip | edge edge part of the opening part opened facing the smoke detection part currently formed in the upper plate-shaped part. Therefore, smoke and steam flowing upward can be flowed downward by the inclined step portion, and the downward inertia acts on steam and the like when the smoke and steam flowing downward hit the projecting portion. Can improve the shunting effect with smoke. Furthermore, the inflow space portion becomes narrower in the height direction at the portion where the flow path is the inclined step portion. Smoke, steam and the like hit the projecting portion in a state where the flow velocity is increased through the narrowed flow path. Thereby, inertia acts strongly on steam and the like, and the shunting action with smoke can be further enhanced.

  Further, according to the present invention, the upper plate-like portion is provided with a plurality of ridges extending radially around the opening on the surface facing the lower plate-like portion. The smoke and steam flowing through the can be collected toward the opening. And the smoke, steam, etc. which flow through the collected upper part can be made to flow below by an inclination step part as mentioned above, and can be shunted up and down by hitting to a projection part.

  Here, in the present invention, there is no need to provide a labyrinth portion having a complicated structure as formed by a large number of conventional light shielding walls, so the surface side of the upper plate portion facing the lower plate portion is not provided. The shape can be simplified. Thereby, for example, it is possible to provide a smoke detection unit cover that covers the smoke detection unit, which has been conventionally formed as a separate part, from below on the surface side facing the smoke detection unit of the upper plate-like part. That is, according to the present invention, the smoke detector cover can be provided on the surface of the upper plate-like portion facing the smoke detector, and the number of parts can be reduced.

It is an example of an embodiment of a photoelectric smoke detector of the present invention, and is a longitudinal sectional view of the entire device It is a disassembled perspective view of the whole apparatus seen from the downward side of the example same as the above. It is a disassembled perspective view of the whole apparatus seen from the upper side of the example same as the above. It is the side view which showed only the smoke inflow member of the example same as the above. It is a longitudinal cross-sectional view of FIG. FIG. 5 is a plan view of FIG. 4. It is the elements on larger scale of FIG.

  An example of an embodiment of the photoelectric smoke detector according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the photoelectric smoke detector 1 is provided with a smoke inflow portion 3 below the smoke detection portion 2, and the smoke detection portion 2 and the smoke inflow portion 3 are arranged in two upper and lower stages. It will be. The smoke flowing in from the lower smoke inflow portion 3 is optically detected in the upper smoke detection portion 2.

  Here, as shown in FIGS. 2 and 3, the photoelectric smoke detector 1 includes a base member 6 for attachment to a mounting surface (such as a ceiling surface) and a smoke detector 2 as main components. The smoke detecting member 4 provided, the smoke inflow member 5 provided with the smoke inflow portion 3, and the cover member 7 covering these members from below are provided. Although details will be described later, in the case of the present embodiment, the smoke inflow member 5 includes a smoke detection unit cover 12 that covers the smoke detection unit 2 from below on the surface facing the smoke detection member 4. I have it. Conventionally, such a smoke detection unit cover had to be molded as a separate part from the smoke inflow member for molding reasons, but according to the present invention, as illustrated in the present embodiment, smoke It can be formed as a part of the inflow member 5, and the number of parts can be reduced.

  In the photoelectric smoke detector 1, the smoke detecting section 2 is provided on the lower surface of the base plate 4 a of the smoke detecting member 4 and on the surface facing the smoke inflow member 5. Specifically, as shown in detail in FIG. 2, the smoke detector 2 includes a cylindrical wall body 11 provided on the base plate 4a, and a light emitting element in which the light emitting element and the light receiving element are respectively housed. While having the accommodating part 8 and the light receiving element accommodating part 9, it is provided as what has the smoke detection space part 10 surrounding the circumference | surroundings by them. For convenience of illustration, optical components such as a light emitting element and a light receiving element are not shown.

  The smoke inflow portion 3 is provided inside the smoke inflow member 5. 4 to 6 are views showing only the smoke inflow member 5 in an enlarged manner. As shown in the drawings, the smoke inflow member 5 has a pair of upper and lower plate-like portions 5 a and 5 b disposed below the smoke detection member 4. The two plate-like parts 5a and 5b are connected in a state of facing and spaced apart from each other in a substantially parallel manner by a plurality of column parts 5c provided between the peripheral parts of the two plate-like parts 5a and 5b. Thus, an inflow space portion 3a is formed between the plate-like portions 5a and 5b as an open space of a blow-off structure whose periphery is opened to the outside. The smoke inflow portion 3 is provided for allowing smoke flowing in from the outside of the inflow space portion 3a to flow into the smoke detecting portion 2. On the other hand, it does not have a labyrinth portion having a complicated structure formed by a number of conventional light shielding walls. The inflow space 3a is specifically formed as an opening between the plurality of support columns 5c, and the periphery is opened to the outside by an inflow port 3b that is an inlet through which smoke flows. That is, the smoke inflow part 3 has the inflow space part 3a and the inflow port 3b as a thing for making the smoke which flows in from the outside into the smoke detection part 2. FIG. In addition, although the smoke inflow part 3 demonstrates as what does not provide an insect screen in the outer peripheral part, you may provide an insect screen.

  Here, in the case of the present embodiment, the smoke detecting member 4 is also provided with a plurality of openings 4b that open facing the outer periphery, and the cover member 7 is also opened facing the outer periphery. A plurality of openings 7a are provided. In the assembled state, the opening 4b and the opening 7a are provided on the outside of the plurality of inflow ports 3b in the smoke inflow portion 3. That is, in the case of this embodiment, the some inflow port 3b in the smoke inflow part 3 is provided as what is open | released outside via these opening part 4b and the opening part 7b.

  In the smoke inflow portion 3, the inflow space portion 3a is formed as an open space having a blow-off structure whose periphery is opened to the outside as described above. Thereby, the airflow flowing in from the peripheral inlet 3b passes through the inside in a horizontal linear shape and flows out from the opposite inlet 3b on the other side.

  In the smoke inflow member 5, the lower plate-like portion 5 b has a truncated cone-like protruding portion 5 d protruding upward in a mountain shape at the center of the surface 5 j facing the upper plate-like portion 5 a. Is provided. The upper plate-like portion 5a is formed with an opening 5e that opens at the center thereof so as to communicate with the smoke detection space portion 10 of the smoke detection portion 2, and the protruding portion 5d penetrates the opening 5e. doing. That is, the upper end portion of the protruding portion 5d is located above the opening portion 5e. Thereby, the inflow space 3a of the smoke inflow part 3 and the smoke detection space 10 of the smoke detection part 2 are communicated with each other in the opening 5e of the upper plate-like part 5a, and smoke is detected from the smoke inflow part 3 side. A communication port 5f having an annular shape (annular shape in the present embodiment) through which smoke flows into the portion 2 side is provided. In the case of this embodiment, the annular shape of the communication port 5f is an annular shape that is continuously opened over the entire circumference, but may be an intermittently opened shape. . Furthermore, the shape of the protruding portion 5d may be a shape that tapers upward, and may be a conical shape that is not truncated. Further, the cross section may not be circular, and may be, for example, a truncated pyramid shape or a pyramid shape.

  The smoke inflow part 3 is configured as described above, and smoke, steam and the like flowing in from the outside flow as shown by arrows in FIG.

  Among the smoke and steam that flow into the inflow space 3a from the inlet 3b of the smoke inflow portion 3, those that do not hit the protruding portion 5d in the middle pass through the inside of the inflow space 3a as shown by the arrow A1. It flows in the direction and flows out from the opposite inlet 3b. On the other hand, in the case of the projecting portion 5d, smoke and steam etc. are shunted up and down due to the difference in mass between them. That is, since smoke is light, as shown by arrow A2, it rises and is shunted upward, and steam and the like are heavy and are shunted downward without rising due to inertia as shown by arrow A3. . Since the smoke that is shunted upward is light, as indicated by the arrow A4, the smoke is guided upward by the protruding portion 5d and flows further upward, and passes through the annular communication port 5f formed around the protruding portion 5d. It passes through and flows into the smoke detection space 10 of the smoke detector 2. On the other hand, the steam or the like which is diverted downward is heavy, and therefore is not guided upward due to inertia, but remains flowing downward. As shown by the arrow A5, the steam wraps backward from both side surfaces of the projecting portion 5d. It flows in the direction and flows out from the inlet 3b on the opposite side. Alternatively, it flows out from the inlet 3b on the side (backward) of the protruding portion 5d.

  In other words, in the smoke inflow portion 3, the smoke that is the detection target out of the smoke and steam flowing into the inflow space portion 3a hits the protruding portion 5d, and flows into the smoke detection portion 2 while being detected. Non-steaming steam or the like can flow out to the outside without staying inside the inflow space portion 3a as well as those that do not hit the protruding portion 5d and those that hit the protruding portion 5d.

  Therefore, in the photoelectric smoke detector 1, the smoke inflow portion 3 is configured as described above, so that the smoke that is the detection target flows into the upper smoke detection portion 2 and is not the detection target. Steam or the like can be prevented from flowing into the upper smoke detector section 2.

  Furthermore, the photoelectric smoke detector 1 of this embodiment will be described in detail.

  In the smoke inflow member 5, the upper plate-like portion 5 a is provided with the opening 5 e that opens toward the smoke detection space portion 10 of the smoke detection portion 2 as described above, and the opening 5 e is in the opening 5 e. An annular communication port 5f is formed, and the opening 5e is provided with an inclined step portion 5g that inclines the mouth edge portion downward. As shown by arrow A6 in FIG. 7, the inclined stepped portion 5g causes the smoke and steam flowing upward to flow downward and hits the protruding portion 5d in that state. As a result, the steam or the like has a downward inertia. On the other hand, since the smoke is light, it is guided upward by the protrusion 5d, so that the shunting action with the smoke can be enhanced. Further, the inflow space 3a is narrowed in the height direction at a portion where the flow path has the inclined step portion 5g. Smoke, steam, and the like increase in flow rate when passing through the narrowed flow path, and hit the protruding portion 5d with the flow rate increased. Thereby, inertia acts strongly on steam and the like, and the shunting action with smoke can be enhanced.

  The upper plate-like portion 5a is provided with a plurality of protrusions 5h extending in the radial direction around the opening 5e on the surface 5k facing the lower plate-like portion 5b. By the plurality of protrusions 5h, smoke, steam, and the like flowing above the inflow space 3a can be collected toward the center (opening 5e). And the smoke, steam, etc. which flow through the collected upper part can be induced | guided | derived below by the inclination step part 5g, and can be shunted up and down against the protrusion part 5d. By setting the number of the protrusions 5h to three or more, the protrusions 5h can be arranged radially around the opening 5e, and smoke and steam flowing upward can be easily collected toward the opening 5e. In the case of the present embodiment, the same number as the plurality of support columns 5c provided on the periphery of the upper plate-like portion 5a is provided, and the periphery of the upper plate-like portion 5a is continuous with the plurality of support columns 5c. Provided to extend from the portion toward the opening 5e. Thereby, the smoke, steam, etc. which flow in from the inflow port 3b provided between several support | pillar parts 5c and flow upwards can be collected smoothly toward the center side.

  In addition, the upper plate-like portion 5 a is provided with a smoke detector cover 12 that covers the smoke detector 2 from below on the surface facing the smoke detector 2. Here, in the present invention, there is no need to provide a labyrinth portion having a complicated structure as formed by a number of conventional light shielding walls, so that the plate-like portion below the plate-like portion 5a above the smoke inflow member 5 The shape on the surface 5k side facing 5b can be simplified. As a result, it is possible to provide a structural part that is conventionally molded as a separate part on the surface facing the smoke detector 2 on the opposite side of the upper plate-like part 5a. It is possible to provide a structural part such as the smoke detection part cover 12 that covers the smoke detection part 2 from below. That is, in the present embodiment, the number of parts can be reduced by providing the smoke detector cover 12 on the surface side of the upper plate-like portion 5a facing the smoke detector 2.

  Further, the frustoconical protrusion 5d provided on the lower plate-like portion 5b has a curved surface 5m that is curved in a concave shape on its outer surface. Thereby, when the steam etc. which are shunted downward hits the protrusion part 5d, it can make it easier to wrap around back.

  Further, the surface 5j facing the upper plate-like portion 5a of the lower plate-like portion 5b that forms the lower surface side of the inflow space portion 3a is gradually inclined upward from the peripheral side toward the center-side protruding portion 5d. Is provided. That is, the inflow space 3a is formed in a shape in which the flow path is gradually narrowed in the height direction from the peripheral side toward the inside toward the central protrusion 5d. Note that the surface 5k facing the lower plate-like portion 5b of the upper plate-like portion 5a that forms the upper surface side of the inflow space portion 3a is also slightly toward the inclined step portion 5g on the center side from the peripheral side. It is provided so as to be gradually inclined downward with a gentler inclination angle than the inclined step portion 5g.

  As mentioned above, although an example of embodiment of the photoelectric smoke detector of this invention was demonstrated, this invention is not limited to said embodiment, A suitable change is possible.

1: Photoelectric smoke detector 2: Smoke detector 3: Smoke inlet
3a: Inflow space part 3b: Inlet port 4: Smoke detection member 4a: Base plate 5: Smoke inflow member 5a: Upper plate-like part 5b: Lower plate-like part 5c: Supporting part 5d: Projection part 5e: Opening part 5f : Communication port 5g: Inclined step 5h: Projection
5j: Surface (lower plate-shaped portion) 5k: Surface (upper plate-shaped portion)
5m: Curved surface 6: Base member 7: Cover member 8: Light emitting element storage part 9: Light receiving element storage part 10: Smoke detection space part 11: Wall body 12: Smoke detection part cover A1 to A6: Smoke and / or steam, etc. Flow of

Claims (4)

In the photoelectric smoke detector where the smoke inflow section is provided below the smoke detection section,
The smoke inflow portion is an inflow space portion formed between a pair of upper and lower plate-like portions, and is formed as an open space whose periphery is opened to the outside, and an airflow flowing from one side of the periphery is a horizontal straight line And is provided as having an inflow space that can flow out from the other side opposite to the inside,
The lower plate-like portion of the pair of upper and lower plate-like portions protrudes upward on the surface side facing the upper plate-like portion and is formed on the upper plate-like portion. Protrusions that pass through the opening facing the smoke part are provided,
Further, the upper plate-like portion of the pair of upper and lower plate-like portions communicates the smoke inflow portion and the smoke detecting portion by passing the opening through the opening in the opening. A photoelectric smoke detector characterized in that the communication port is formed in a ring shape.   The photoelectric smoke detector according to claim 1, wherein the opening is provided with an inclined step portion that is inclined downward inward at a mouth edge thereof.   The upper plate-like portion is provided with a plurality of ridges extending radially around the opening on a surface facing the lower plate-like portion. The photoelectric smoke detector according to 1 or 2.   The smoke detection part cover which covers the said smoke detection part from the downward direction is provided in the said upper plate-shaped part on the surface side which opposes the said smoke detection part, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. The photoelectric smoke detector according to item 1.

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