JP2012226657A - Alarm unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin type alarm unit which makes a good response in whatever direction smoke flows.SOLUTION: The alarm unit includes a case C which has a flat front shape and allows smoke to flow in from an outer peripheral part and a photoelectric smoke sensor 6 which is arranged in the case C, and has a plurality of smoke introduction holes 63 and in which the smoke flowing in the case C is introduced from the smoke introduction holes 63 to be sensed, includes a plurality of smoke guide parts 21, 22 which extend toward the outer peripheral part starting at the smoke introduction holes 63, and guide the smoke flowing in the case C to the smoke introduction holes 63, and includes one or more of closed areas 24, 25, 26, and 27 which are provided between the smoke sensor 6 and outer peripheral part of the case C nearby the outer peripheral part and to which the smoke flowing in the case C does not circulate, one of the areas 24, 25 including the smoke guide part 22 whose end does not reach the outer peripheral part on at least one of both sides of the area 24, or 25.

Description

  In the present invention, the front shape is a flat shape, a case that allows the inflow of smoke from the outer peripheral portion, and a plurality of smoke inlets disposed in the outer peripheral portion and disposed inside the case. A photoelectric smoke sensor that introduces and senses inflowing smoke into the interior, extends toward the outer periphery of the case from the smoke introduction port, and smoke that flows into the case The present invention relates to an alarm device provided with a plurality of smoke guide sections.

  Conventionally, there has been an alarm device described in Patent Document 1 as such an alarm device. In the alarm device described in Patent Literature 1, the smoke sensor (in the literature, “smoke detection unit”) is not projected forward of the case (in literature, “housing”), but is retracted into the case and the case This enables a smoke inflow from the outer periphery of the slab, and is a thin alarm device. And since the smoke sensor was retreated inside the case, a smoke guide part (in the literature, "guidance wall") where the end reaches the outer peripheral part of the case while the smoke introduction port is a starting point is preferably disposed, Smoke is appropriately guided from the outer periphery of the case to the smoke sensor.

  And in the alarm device of patent document 1, the closed area | region where the smoke which flowed into the inside of a case cannot distribute | circulate between the outer peripheral part of a smoke sensor and the outer peripheral part of a case in the vicinity of the outer peripheral part of a case (references) In the case where one or more “structures” are provided, the arrangement of the smoke guiding portion is appropriately changed to cope with the smoke circulation.

JP 2009-230647 A (paragraphs [0080] to [0111], FIGS. 8 to 13)

  However, in the alarm device described in Patent Document 1, even if smoke can appropriately flow into the spaces on both sides of the closed area, the area closed with the smoke guide portion sandwiched depending on the direction of smoke flow. It may be difficult for smoke to enter the opposite area. The smoke sensor must be able to detect smoke from any direction (eight surrounding directions) with a certain response speed. In such a case, the inflow of smoke is biased and the response speed decreases. There is a possibility.

  In view of the above circumstances, an object of the present invention is to provide a thin alarm device with good responsiveness regardless of the direction of smoke flow.

  The first characteristic configuration of the alarm device according to the present invention is that a front shape is a flat shape, a case that allows inflow of smoke from the outer peripheral portion, and a plurality of smoke inlets that are disposed inside the case. And a photoelectric smoke sensor that senses smoke flowing into the case by introducing the smoke into the case from the smoke introduction port, and is directed toward the outer peripheral portion with the smoke introduction port as a starting point. And a plurality of smoke guide portions for guiding smoke flowing into the case to the smoke inlet, and provided between the smoke sensor and the outer peripheral portion in the vicinity of the outer peripheral portion. One or more closed areas in which smoke that has flowed into the area cannot flow, and at least one of the areas, at least one of both sides of the area, the end does not reach the outer periphery The point is that it has a guide.

  According to this configuration, the end of the smoke guide wall next to the closed area does not reach the outer periphery of the case, so that no matter what direction the smoke flows, Smoke tends to flow into the space opposite to the closed area. Therefore, with this feature configuration, there is no bias in the inflow of smoke, and the response speed does not decrease.

  It should be noted that the expression “front shape is flat” according to this feature configuration indicates that the smoke sensor is not a shape protruding from the case but has been retreated into the case, and the front of the case is somewhat uneven. It does not exclude what is.

It is a perspective view of the alarm device which concerns on this invention. It is a front view of the alarm device which concerns on this invention. It is a side view (top view) of the alarm device according to the present invention. It is sectional drawing (back view) of the IV-IV direction in FIG. It is sectional drawing of the VV direction in FIG. It is a disassembled perspective view from the front side of the alarm device which concerns on this invention. It is a schematic diagram which shows the mode of inflow of the smoke from the CO sensor side, Comprising: (a)-(c) changes the inflow direction of smoke.

  Hereinafter, embodiments of an alarm device according to the present invention will be described with reference to the drawings.

[About overall configuration]
As shown in FIGS. 1, 2, 4, and 5, the alarm device allows the inflow of the gas to be detected and allows the inflow of smoke from the outer periphery, and the detected gas that has flowed into the case C. Is fixed to the wall surface W (see FIG. 5) or the ceiling surface, the photoelectric smoke sensor 6 for detecting the smoke flowing into the case C, the battery accommodating portion 42 for accommodating the battery B, and the ceiling surface. And a mounting portion 5 from which the case C can be removed. That is, the alarm device according to the present invention is a composite alarm device capable of detecting a gas to be detected and detecting smoke. In the present embodiment, the “gas sensor” is the CO sensor 7, which detects CO (carbon monoxide) gas.

  As shown in FIG. 5, the smoke sensor 6 and the CO sensor 7 are attached to the front side of the substrate 9 and are located in a distribution space S <b> 1 described later. When the smoke sensor 6 detects smoke and the smoke concentration exceeds a preset threshold value, or when the CO sensor 7 detects CO gas and the CO gas concentration exceeds a preset threshold value, A warning sound is emitted from the speaker 8 built in the case C. If the switch 11 provided on the surface of the case C is pressed, the alarm sound is stopped.

  Hereinafter, on the premise that the alarm device is installed on the wall surface W (see FIG. 5), the side opposite to the wall surface W is defined as the front side or the front side, and the side of the wall surface W is defined as the back side or the rear side. Therefore, “front view” indicates that the alarm device is viewed from the front side, and “back view” indicates that the alarm device is viewed from the back side. As for the up and down direction, the explanation will be made assuming that the upper direction in FIGS. 1, 2, 4, 5 and 7 is “up” of the alarm device and the lower direction is “down”. In FIG. 3, the front direction on the paper is “up”, and in FIG. 6, the left direction on the paper is “up”. “Thickness” refers to the thickness in the front-rear direction, and “thickness direction” refers to the front-rear direction of the alarm device.

[About Case C]
As shown in FIGS. 1, 3, 5, and 6, the case C includes a front case 1, a rear case 2, an intermediate case 3, and a rear case cover 4, and has a circular shape in front view. It is a flat shape with no protruding part in the direction. The front case 1, the rear case 2, the rear case cover 4, and the intermediate case 3 are made of resin and are manufactured by injection molding. As shown in FIGS. 5 and 6, the front case 1, the rear case 2, the rear case cover 4, and the intermediate case 3 all have a circular shape having substantially the same diameter in front view.

  The front case 1 serves as a decorative cover on the front side, and its surface is generally flat as shown in FIGS. 1, 3 and 3. However, in detail, the thickness of the center portion is the most. It is thick and slightly inclined toward the outer peripheral part, and the outer peripheral part is slightly thinner than the central part. As shown in FIG. 2, an acoustic port 13 for the speaker 8 is opened above the center on the front side of the front case 1, and a gas circulation port 14 through which CO gas can be circulated is opened at the upper right part from the center. It is. In addition, a ring-shaped lamp cover 12 is disposed at the center of the front case 1 on the front side. The lamp cover 12 covers a lamp (such as a light bulb or a light emitting diode) (not shown) disposed inside the case C. When the lamp is turned on or blinking, the lamp notifies an alarm together with an alarm sound, and also notifies information other than the alarm (such as battery exhaustion or failure).

  As shown in FIG. 6, the rear case 2 has a generally cylindrical shape with a bottom, and is disposed such that the side with the bottom becomes the side of the front case 1, and is greatly opened on the rear side. As shown in FIGS. 1, 3 to 6, the outer periphery of the rear case 2 is formed in a horizontal lattice shape and an inflow port 23 is provided. Smoke and CO gas can flow into and out of the case C from the inlet 23. As shown in FIG. 4, ribs 21 and 22 as “smoke guide portions” to be described later are erected on the rear side of the rear case 2 in the rear direction. A part of the ribs 21 constitutes a closed area such as a CO sensor accommodating portion 24 that accommodates the CO sensor 7 and closed areas 25, 26, and 27 described later.

  As shown in FIG. 2, the CO sensor accommodating portion 24 is disposed on the right side of the central portion of the alarm device in a front view so as to be oriented in a direction (vertical direction) perpendicular to the circular radial direction of the case C. Has been. As shown in FIG. 4, a plurality of gas inlets 28 through which CO gas can be circulated are provided in the upper portion of the outer peripheral surface of the CO sensor accommodating portion 24. In addition, the gas distribution port 14 mentioned above is connected to the upper part of the CO sensor accommodating part 24, as shown in FIG.

  Further, on the front side of the rear case 2, there are provided a recess (not indicated) for accommodating the speaker 8 and an opening (not indicated) for communicating the gas flow port 14 of the front case 1 and the CO sensor accommodating portion 24. is there.

  As shown in FIG. 5, the rear case cover 4 covers the back side of the rear case 2 and constitutes the back side of the case C. As shown in FIGS. 2 and 6, a portion of the rear case cover 4 on the upper left side from the center in the front view is recessed toward the front side to form a battery accommodating portion 42. That is, the battery B can be easily removed from the back side of the case C without disassembling the case C. As shown in FIG. 2, the battery housing portion 42 is disposed so as to be oriented in a direction orthogonal to the circular radial direction of the case C in a front view.

  Thus, the front case 1 constitutes the front surface of the case C, the rear case 2 constitutes the outer peripheral surface of the case C, and the rear case cover 4 constitutes the back surface of the case C. As shown in FIG. 5, the space enclosed by the front case 1, the rear case 2, and the rear case cover 4 is divided into two in the front-rear direction by the intermediate case 3, and the distribution space S 1 on the front side of the intermediate case 3 A substrate space S2 on the rear side of the intermediate case 3 is formed. The CO sensor 7 and the smoke sensor 6 are disposed in the distribution space S1, and the substrate 9 is disposed in the substrate space S2.

  As the size (thickness) of the substrate space S2 in the front-rear direction is sufficient if the substrate 9 can be disposed, the intermediate case 3 has a battery housing portion 42 as shown in FIGS. An opening corresponding to the shape (not indicated) is provided, and a part of the battery housing portion 42 is protruded into the circulation space S1. As a result, the substrate space S2 is thin, and the thickness of the case C is not increased unnecessarily. Further, as shown in FIG. 6, an intermediate case is formed so that the CO sensor 7 and the smoke sensor 6 (see FIG. 5) attached to the front side of the substrate 9 are positioned in the circulation space S1. 3 is provided with openings (not indicated) corresponding to the shapes of the CO sensor 7 and the smoke sensor 6.

[Mounting section]
The attaching portion 5 is fixed to the wall surface W (see FIG. 5) prior to the case C. The attachment portion 5 is made of resin and is manufactured by injection molding. Although not particularly illustrated, the attachment portion 5 is formed with a hole through which a fixing tool such as a plaster board pin can be inserted. Further, the fixing tool may be a fastener such as a screw, and the mounting portion 5 may be provided with a screw hole in addition to the hole for the gypsum board pin. The case C is attached to the attachment portion 5 attached to the wall surface W by engagement or the like.

[About the smoke sensor]
As shown in FIGS. 4 and 6, the smoke sensor 6 has a cylindrical shape, and is provided uniformly on the outer peripheral portion so as to block smoke from a plurality of smoke inlets 63 through which smoke can be introduced. A plurality of labyrinth-like wall portions (not shown) juxtaposed via a gap, a light emitting portion 61 for irradiating light inside the smoke sensor 6, and a light emitting portion scattered by the smoke flowing into the smoke sensor 6 A light receiving unit 62 that senses light from 61.

  Since the smoke inlet 63 is provided uniformly on the outer periphery of the smoke sensor 6, the smoke sensor 6 can sense the smoke regardless of the direction of 360 degrees from which direction the smoke flows into the case C. The light emitting unit 61 and the light receiving unit 62 are provided along the outer peripheral portion of the smoke sensor 6 with a central angle of about 90 degrees in a state directed toward the center of the smoke sensor 6. Of the outer periphery of the smoke sensor 6, the portion that is the back surface of the light emitting unit 61 and the light receiving unit 62 is closed with a wall for light shielding. Further, as the light emitting unit 61, for example, an issuing diode is used, and as the light receiving unit 62, for example, a photodiode is used. Although not shown in particular, an insect net is provided on the outer peripheral side of the smoke inlet 63. Since the smoke sensor 6 has a known configuration, the configuration of the other smoke sensor 6 is not particularly described.

[About CO sensor]
The CO sensor 7 is accommodated in the CO sensor accommodating portion 24 as shown in FIGS. The CO sensor 7 is, for example, an electrochemical sensor, and detects CO gas in incomplete combustion exhaust gas that has flowed into the CO sensor housing portion 24 from the gas flow port 14 or the gas introduction port 28. In this way, not only the smoke sensor 6 but also the CO sensor 7 is provided, and by detecting carbon monoxide due to incomplete combustion, it is possible to detect fire early and prevent CO poisoning.

[Assembling the case]
The assembly of the case C will be described in detail with reference to FIGS. The back side of the front case 1 and the front side (bottom part) of the rear case 2 are set back to back. In the space between the front case 1 and the rear case 2, a speaker 8 and a lamp are disposed.

  Separately, the substrate 9 is set on the front side of the rear case cover 4 so that the smoke sensor 6 and the CO sensor 7 are on the front side, and further, the intermediate case 3 is attached to the rear case from the front side so as to cover the substrate 9. Set on cover 4. At this time, the smoke sensor 6, the CO sensor 7, and the battery housing portion 42 penetrate the intermediate case 3 and are exposed to the front side.

  Finally, a recovery case cover is set on the rear case 2. At this time, the rear case cover 4 and the front case 1 are fixed by screws from the rear side of the rear case cover 4. Thereby, the rear case 2 and the intermediate case 3 are sandwiched and fixed by the front case 1 and the rear case cover 4.

[About the layout of each part]
The layout of each part in the case C will be described. First, the positional relationship among the smoke sensor 6, the CO sensor 7, and the battery housing portion 42 will be described. First, as shown in FIG. 4, the smoke sensor 6 is located on the right side of the center of the case C so that the light emitting unit 61 is located on the upper left side and the light receiving unit 62 is located on the upper right side in the rear view. It is arranged on the lower side.

  As shown in FIG. 4, the CO sensor 7 is disposed slightly to the left with respect to the smoke sensor 6 in the rear view. That is, the CO sensor 7 is disposed so as to be located behind the light emitting unit 61 with the center of the smoke sensor 6 as a reference. In addition, as described above, the CO sensor 7 is oriented in a direction orthogonal to the circular radial direction of the case C, but is not orthogonal to the circular radial direction of the smoke sensor 6, It is a slightly inclined posture.

  As shown in FIG. 4, the battery housing portion 42 is disposed substantially upward with respect to the smoke sensor 6 in the rear view. That is, the battery housing part 42 is disposed so as to be located behind the light receiving part 62 with respect to the center of the smoke sensor 6. Further, as described above, the battery housing portion 42 is also oriented in a direction orthogonal to the circular radial direction of the case C, but is not orthogonal to the circular radial direction of the smoke sensor 6. A slightly inclined attitude.

  That is, since the CO sensor 7 and the battery housing portion 42 are in a posture orthogonal to the circular radial direction of the case C, the CO sensor 7 and the battery housing portion 42 are most compactly housed in the case C. Further, since the CO sensor 7 and the battery housing portion 42 are not orthogonal to the circular radial direction of the smoke sensor 6, the width of the CO sensor 7 and the battery housing portion 42 that are found based on the smoke sensor 6. Becomes narrow, and the flow of smoke to the smoke sensor 6 is difficult to be hindered. Furthermore, since the CO sensor 7 and the battery housing part 42 are located on the back side of the light emitting part 61 and the back side of the light receiving part 62 that are blocked by the wall with respect to the center of the smoke sensor 6, Less impact on distribution.

  Further, in the thickness direction of the case C, as shown in FIG. 5, the smoke sensor 6, the CO sensor 7, and the battery housing portion 42 are arranged inside the case C so that a part of their occupied ranges overlap each other. It is arranged. That is, by integrating these as much as possible in the thickness direction of the case C and compactly accommodating them in the case C, a thin alarm device is obtained.

  As shown in FIG. 4, the battery housing portion 42 is arranged in a posture over the entire area in the width direction (left and right direction on the paper surface) of the smoke sensor 6 in the substantially upward direction of the smoke sensor 6. Further, as shown in FIG. 5, a gap G is provided between the battery housing portion 42 and the rear portion of the rear case 2. Therefore, when the alarm device is mounted on a wall and used, even if dust or the like enters the case C from above the alarm device, the battery housing portion 42 becomes a shade and the dust reaches the smoke sensor 6. Can be prevented. Even if smoke flows from above, since the gap G is provided, a certain amount of smoke is introduced into the smoke sensor 6 from the gap G, and a decrease in response speed can be suppressed.

[About ribs]
The smoke flowing in from the inflow port 23 is guided to the ribs 21 and 22 (see FIG. 4) and reaches the smoke introduction port 63. As described above, the ribs 21 and 22 are erected from the back side of the rear case 2 toward the back side, and the tips thereof are in contact with the intermediate case 3. That is, as shown in FIG. 5, the ribs 21 and 22 partition the circulation space S1 into a plurality of flow paths.

  As shown in FIG. 4, the rib 21 extends from the smoke inlet 63 toward the outer peripheral portion of the case C, and the end reaches the outer peripheral portion of the case C. On the other hand, the rib 22 similarly extends from the smoke introduction port 63 toward the outer peripheral portion of the case C, but the end does not reach the outer peripheral portion of the case C. Regardless of which rib (21, 22), the provision of the ribs 21, 22 makes it possible to smoothly guide the inflowing smoke to the smoke inlet 63 regardless of the direction in which smoke flows. The reason why the end of the rib 22 does not reach the outer periphery of the case C will be described later.

  Further, as shown in FIG. 4, the rib 21 closes the space between the CO sensor 7 and the smoke sensor 6 to form a closed closed region 25. The closed region 25 is a region that is integrated with the CO sensor accommodating portion 24 and is formed over the entire range between the outer peripheral portion of the case C and the outer peripheral portion of the smoke sensor 6. As described above, since the smoke sensor 6, the CO sensor 7, and the battery housing portion 42 are aggregated in the thickness direction in order to configure the alarm device to be thin, the ratio occupied by the CO sensor 7 in the distribution space S <b> 1 is high. . Further, since the CO sensor accommodating portion 24 extends over the rear side of the rear case 2 and the front side of the intermediate case 3 in the circulation space S1, if there is a gap between the CO sensor 7 and the smoke sensor 6, the CO sensor The smoke flowing into the case C after passing through the flow passages A1 and A2 on both sides of the air flow 7 is entangled in the gap immediately after dodging the CO sensor 7 and is disturbed by convection and the like, and the smoke introduction port 63 smoothly. Are not introduced into the smoke sensor 6. For this reason, there is a possibility that the response speed of smoke detection is lowered.

  However, since the gap is closed by the rib 21 to form the closed region 25, the smoke is smoothly guided from the smoke inlet 63 to the smoke inlet 63, and the above-described flow is not disturbed. Similarly, the outer peripheral wall 41 erected from the outer peripheral portion on the front side of the rear case cover 4, the screw boss for assembling the front case 1 and the rear case cover 4, etc., can cause disturbance of the flow of smoke. The portions are surrounded by ribs 21 to form closed regions 26 and 27.

[Inflow of smoke from a specific direction]
The rib 22 whose end does not reach the outer peripheral portion of the case C will be described with reference to FIGS. In the present embodiment, as shown in FIG. 4, the length of the CO sensor 7 in the longitudinal direction (vertical direction) exceeds 1/2 of the diameter of the case C. Therefore, when smoke flows from a direction perpendicular to the longitudinal direction of the CO sensor 7 (see FIG. 7B) or a direction close thereto (see FIGS. 7A and 7C), the smoke flows from the inlet 23. The amount of smoke flowing into the case C tends to be small. In this case, the amount of smoke introduced into the smoke inlet 63 corresponding to that direction is reduced, and the response speed to the smoke from that direction may be reduced. Accordingly, the ribs 21 and 22 are bent in the middle so that the flow passage A1 and the flow passage A2 adjacent to the CO sensor accommodating portion 24 expand in a trumpet shape as they approach the outer peripheral portion of the case C, and the corresponding inflow ports. The opening of 23 is widened so that as much smoke as possible can flow in.

  Incidentally, a closed region 26 exists on the opposite side of the CO sensor accommodating portion 24 across the rib 22. This closed region 26 is different from the closed region by the CO sensor accommodating portion 24 and the closed region 25 so as not to cover the entire range between the outer peripheral portion of the case C and the outer peripheral portion of the smoke sensor 6. Yes, a flow passage A3 is formed. This is because if the area is closed between the closed area 26 and the outer periphery of the smoke sensor 6, the amount of smoke inflow from the vicinity of the CO sensor accommodating section 24 is considerably reduced. The closed region 26 has a relatively narrow width in the circumferential direction, and one side of the region between the closed region 26 and the outer periphery of the smoke sensor 6 is partitioned by the rib 21, so that the smoke that has flowed in Disturbance does not occur so much.

  However, if the end of the rib 22 reaches the outer periphery of the case C, when smoke flows from the direction as shown in FIGS. 7B and 7C, the flow passage A1 and the flow passage A2 Smoke appropriately flows in, but the flow path A3 is blocked by the end portion of the rib 22 so that almost no smoke flows, and eventually the response speed to smoke from those directions decreases.

  Therefore, in the present embodiment, the rib 22 is prevented from reaching the outer peripheral portion of the case C. Accordingly, as shown in FIGS. 7A, 7B, and 7C, the direction perpendicular to the longitudinal direction of the CO sensor 7 (see FIG. 7B) or a direction close thereto (FIG. 7A). , (C)), when smoke flows from the smoke introduction port 63, the smoke is smoothly and uniformly introduced into the smoke introduction port 63 on the CO sensor 7 side. As a result, the CO sensor accommodating portion 24 It is suitably prevented that the response speed decreases due to the provision of.

  The battery housing part 42 is also a wide area as with the CO sensor housing part 24, but as described above, there is a gap G between the back surface of the rear case 2 and the battery housing part 42 (see FIG. 5), the amount of inflow with respect to the smoke from the direction of the battery accommodating portion 42 can be secured.

[Another embodiment]
(1) Although the front view shape of the case C is circular in the above-described embodiment, it is not limited to this shape. The shape of the case C viewed from the front may be a shape other than a circular shape, for example, a polygonal shape such as a triangular shape or a quadrangular shape, or an elliptical shape.

(2) In the above-described embodiment, an example in which the gap G is provided between the battery housing portion 42 and the rear portion of the rear case 2 has been described, but a configuration in which the gap G is not provided may be employed. . In this case, in order to ensure the amount of smoke inflow from the direction of the battery housing portion 42, the gap between the battery housing portion 42 and the outer periphery of the smoke sensor 6 is appropriately closed by the rib 21 so that A region may be formed or the rib 22 may be provided around the periphery.

(3) In the above-described embodiment, the closed region 26 is shown on the opposite side of the CO sensor accommodating portion 24 with the rib 22 interposed therebetween. However, for example, the single rib 21 reaching the outer peripheral portion of the case C is used. May be. Also in this case, the rib 22 has the same effects as described above.

(4) In the above-described embodiment, the example in which the ribs 22 are provided only on one side of the both sides of the sensor housing portion 24 has been described. However, the ribs 22 are provided on both sides of the sensor housing portion 24 as necessary. It may be provided. Further, the closed area is not limited to the sensor accommodating portion 24, and may be another closed area (closed areas 26, 27, etc.). Then, ribs 22 may be provided on one side or both sides adjacent to another closed region. In addition, when the closed area | regions adjoin and there is only one rib between them, the rib 22 may be shared.

  The present invention is not limited to an alarm device including a CO sensor and a smoke sensor, but can also be applied to an alarm device including another gas sensor and a smoke sensor, and also to an alarm device including only a smoke sensor. Applicable.

6 Smoke sensor 21 Rib (smoke guide)
22 Rib 24 CO sensor housing (closed area)
25 Closed area (closed area)
26 Closed area (closed area)
27 Closed area (closed area)
63 Smoke inlet C Case

Claims (1)

The front shape is a flat shape, and the case that allows the inflow of smoke from the outer periphery,
A photoelectric smoke sensor which is disposed inside the case and has a plurality of smoke inlets, and detects smoke flowing into the case by introducing the smoke into the case from the inside. ,
A plurality of smoke guide portions extending toward the outer peripheral portion starting from the smoke inlet, and guiding the smoke flowing into the case to the smoke inlet;
Provided between the smoke sensor and the outer peripheral part in the vicinity of the outer peripheral part, comprising one or more closed areas where the smoke flowing into the case cannot flow,
An alarm device comprising the smoke guide portion whose end does not reach the outer peripheral portion on at least one of both sides of the region for at least one of the regions.

Images