JP2022116561A - Smoke detector - Google Patents

Abstract

To provide a smoke detector in which a visibility is good at a lighting of an operation display light, and which is not noticeable at the time of non-lighting of the operation display light.SOLUTION: A fire detector (smoke detector) comprises: a housing comprising a main body part, and a cover member covering a whole of an upper side of the main body part; a circuit board which is housed in the housing and implemented with an electron circuit comprising a sensor part having a photoelectric smoke sensor; and an insect screen which is visible form an outside. The cover member comprises: a cover main body part having an open part to which the sensor part face; a head part covering the sensor part; and multiple columns which connect the head part and the cover main body part, and formed respectively with smoke inflow ports therebetween. The cover member further has a light emitting part constituting a pilot lamp, and mounted with a light emitting member arranged the light emitting part is directed toward a front face side of the cover member. Further, the cover member is mounted with an opaque coated layer, which is arranged, allowing light to leak, to cover a lower side of the light emitting part in a state that the fire detector is installed in a ceiling plane of a building, and which has a color similar to a color of the front surface of the cover member.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a fire sensor, and more particularly to a technique effectively applied to a fire sensor (smoke sensor) using a photoelectric smoke sensor comprising a light emitting element and a light receiving element.

Conventionally, as a fire detector, there has been known a smoke detector using a photoelectric smoke sensor, which senses smoke by detecting light emitted from a light-emitting element scattered by smoke particles and receiving the scattered light with a light-receiving element. there is
The photoelectric smoke sensor of the smoke detector contains the light emitting element and the light receiving element with their optical axes shifted in a dark box surrounded by a labyrinth-structure light shielding wall that prevents light from entering from the outside. However, when smoke flows into the dark box when a fire occurs, the light emitted from the light emitting element is scattered by smoke particles, and when the light receiving element detects the scattered light, it is determined that a fire has occurred and an alarm is generated. there is something

By the way, fire detectors are generally installed in white, which is often used as the color of the environment in which they are installed, so that they are not conspicuous in the non-fired state because the ceilings of many fire prevention objects are white. The surface color of the container (case) is often based on white. On the other hand, an operation indicator lamp that lights up or flashes when a fire is detected is required to have good visibility when it is lit up, for example, when installed on a ceiling surface. For this reason, a window is provided in a part of the sensor main body (housing) so that the luminous indication of the spot-shaped operation indicator lamp can be seen through the window (for example, Patent Document 1). There is also a smoke sensor provided with a plurality of operation indicator lamps in order to improve visibility from all directions of 360° (for example, Patent Document 2).

JP-A-2001-126165 JP 2013-8084 A

Since the ceiling surface on which the fire detector is installed is often white or whitish, it is possible to make the fire detector inconspicuous by installing the fire detector based on white that matches the installation environment. In the case where the fire sensor is a heat sensor, it is possible to form the sensor without providing any detection openings at all, depending on the detection element to be used, since it is sufficient to detect the conduction of heat. However, for a smoke detector using a photoelectric smoke sensor, it is essential for smoke detection to take in the smoke particles to be detected. An insect screen is installed near the smoke sensor to surround it. Since insect screens for conventional smoke detectors are dark in color, by making the body of the smoke detector white to match the color of the environment, even if the smoke detector is not conspicuous, the dark color will pass through the smoke inlet. The problem is that the insect screen is conspicuous, and the smoke detector as a whole does not match the surrounding color. In addition, the smoke detector is configured to have a dark box that houses the smoke sensor, but because the dark box is made of black resin due to its characteristics, a part of it is visible through the insect screen, so it is difficult to install. Even if a fire sensor based on white that matches the environment is installed, there is a problem that the dark color of the dark box that can be seen through the insect screen stands out.

In addition, as in the smoke sensor of Patent Document 2, when an operation indicator light is provided, the operation indicator light is formed of a transparent or translucent material to guide light. The surface of the detector case (outer cover), which is based on white to match the environment, is exposed to the operation indicator lamps of different colors. There is a problem that the operation indicator light stands out because it is not in harmony with the white color that matches the color.

The present invention has been made in view of the above problems, and its object is to provide a smoke detector using a photoelectric smoke sensor, in which visibility is improved when the operation indicator lamp is activated (lighted). To make a good operation indicator lamp inconspicuous when it is not operated (not lit).
Another object of the present invention is to provide a smoke sensor that can be adapted to the installation environment by preventing components such as an insect net, a dark box, and a dark box base from being conspicuous.

In order to achieve the above object, the present invention
A sensing unit equipped with a photoelectric smoke sensor and an electronic circuit for detecting the occurrence of a fire based on a signal from the sensing unit are placed inside a housing composed of a main body and a cover member covering the upper side of the main body. A smoke sensor containing a mounted circuit board and equipped with an insect screen visible from the outside,
The cover member is provided with a cover body portion having an opening facing the sensing portion, a head portion covering the sensing portion, and a plurality of pillars connecting the head portion and the cover body portion, A smoke inlet is formed between each of the pillars,
a light emitting member having a light emitting portion that constitutes an operation indicator lamp, the light emitting member being disposed so that the light emitting portion faces the surface side of the cover member;
An opaque coating layer having a color similar to that of the surface of the cover member is provided so as to cover the light emitting portion so as to allow light to leak.

According to the smoke sensor having the configuration as described above, since the coating layer having the same color as the surface color of the cover member is provided so as to cover the light-emitting portion constituting the operation indicator light, the operation indicator light is non-functional. When lit, it can be made inconspicuous by harmonizing with the color of the installation environment. In addition, since the coating layer covering the light emitting portion can leak light, the lighting state of the operation indicator lamp can be visually recognized when it is lit.
Here, the operation indicator lamp is annular and arranged in the vicinity of the opening of the cover member and outside the pillar.
As a result, the light emitting portion has an annular shape, so that visibility from all directions is improved when the operation indicator lamp is lit.

Further, the coating layer is a coating formed on the exposed surface of the light emitting portion.
According to such a configuration, it is only necessary to form a film on the surface of the exposed side of the light emitting portion. It can be matched and discreet with the color of the

Alternatively, the light emitting member is disposed inside the cover member,
The covering layer is formed on a portion of the cover member facing the light emitting portion.
According to this configuration, it is sufficient to form the coating layer on the portion facing the light emitting portion of the cover member, so that the sensor can easily match the color of the installation environment and be inconspicuous when the operation indicator lamp is not lit. can do.

Further, desirably, the portion is a thin-walled portion, and is formed in a portion excluding at least the vicinity of the plurality of pillars.
According to such a configuration, since the thickness of the cover member is increased in the vicinity of the column connecting the head portion and the cover main body portion, it is possible to avoid a decrease in the strength of the base portion of the column, and the external force applied to the head portion can be avoided. It is possible to make it difficult for deformation to occur even if

Further, preferably, the housing includes the insect net facing the smoke inlet and disposed so as to surround the sensing unit,
The insect screen is formed with a layer having a similar color to the surface color of the cover member on its outer surface, or is entirely made of a resin having a color similar to the surface color of the cover member.
According to such a configuration, the surface of the insect screen and the surface of the surrounding cover member have the same color, so that the insect screen itself can be prevented from being conspicuous, and the sensor can be adapted to the installation environment.

Further, desirably, the sensing unit includes a dark box containing the photoelectric smoke sensor and a dark box base for holding the dark box, and the dark box has a storage space inside for storing the photoelectric smoke sensor. A light shielding wall having a labyrinth structure is provided outside the storage space,
At least the portion of the light shielding wall that is in contact with the insect net is colored in the same color as the surface color of the cover member.
According to this configuration, the part of the light shielding wall inside the insect screen that contacts the insect screen has the same color as the surface of the cover member. It can prevent you from standing out.

Further, desirably, the dark box base is provided with ribs into which the openings of the cover members can be fitted, and the upper surface of the ribs and a part of the inner peripheral surface of the ribs on the side of the dark box are: It should be colored in the same color as the surface color of the cover member.
According to this configuration, since the upper surface and inner peripheral surface of the rib of the dark box base into which the opening of the cover member is fitted and the surface of the surrounding cover member have similar colors, the dark box base is prevented from being conspicuous. can do.

Further, preferably, a space serving as a light projection path or a light-transmitting member is provided between the light emitting portion and the insect screen.
According to such a configuration, the surface of the insect screen is irradiated with the light emitted from the light emitting portion, so that the outer peripheral surface of the insect screen can be used to display the operation.

According to the present invention, in a smoke sensor using a photoelectric smoke sensor, visibility is good when the operation indicator lamp is on, and it can be made inconspicuous when the operation indicator lamp is off. In addition, there is an effect that parts such as an insect net, a dark box, and a dark box base can be prevented from being conspicuous, and the smoke sensor can be adapted to the installation environment.
In addition, since the visible part of the smoke sensor can be unified in the same color, it is possible to realize an inconspicuous smoke sensor with a color scheme that matches the color of the required installation environment.

1 is an exploded perspective view showing an embodiment of a smoke sensor having a photoelectric smoke sensor according to the present invention; FIG. It is a central sectional view showing the internal configuration of the smoke sensor of the embodiment. FIG. 2 is a perspective view of an upside-down outer cover that constitutes the smoke sensor of the embodiment shown in FIG. 1 ; FIG. 3 is an enlarged cross-sectional view of a main part showing details of a connecting portion between a sensor main body and a main body cover that constitute the smoke sensor of the embodiment; FIG. 4 is a central cross-sectional view showing the internal configuration of a smoke sensor according to a second embodiment of the present invention; (A) is an enlarged cross-sectional view of the locking claw forming portion of the outer cover of the smoke sensor of the second embodiment; (B) is an enlarged cross-sectional view of the column forming portion of the outer cover; ) and (B) are enlarged cross-sectional views of inner rib formation portions. FIG. 4 is a perspective view showing an example of a display form by a light emitting portion of an outer cover of the smoke sensor; FIG. 4 is a central cross-sectional view showing the internal configuration of another embodiment of the smoke sensor according to the present invention;

An embodiment of a smoke sensor to which the present invention is applied will be described below with reference to the drawings.
The smoke sensor 10 of this embodiment is a sensor capable of sensing smoke generated by a fire, and is configured to be installed on the ceiling surface of a building or the like for use. In the following description, unless otherwise specified, the upper side of the smoke sensor 10 installed on the ceiling surface of the building is referred to as the lower side, and the lower side is referred to as the upper side.

As shown in FIG. 1, the smoke sensor 10 of the present embodiment has a housing recess 11A for housing a sensing portion, and has a cylindrical main body case 11 for mounting on the ceiling surface of a building. and an outer cover 12 that has an opening serving as a smoke inlet and covers the entire upper side of the main body case 11, and has an accommodation space inside by the main body case 11 and the outer cover 12 body is formed.
The main body case (main body portion) 11 is not limited to the structure shown in FIG. 1, and may have any structure as long as it can accommodate the constituent members and parts constituting the smoke sensing function.
Further, the smoke sensor 10 includes a circuit board 13 accommodated and fixed in the accommodation recess 11A of the main body case 11, a dark box base 14 having a light shielding wall of labyrinth structure and mounted on the circuit board 13, A cylindrical insect net 15 which is engaged and placed inside the edge of the dark box base 14, and a dark box cover 16 which engages with the dark box base 14 with the insect net 15 interposed therebetween to form a dark box. These constituent members are accommodated in the housing, and the main body case 11 and the outer cover 12 are coupled to form a sensor.

The main body case 11 constitutes the lower housing wall of the smoke sensor 10, and the lower surface of the main body case 11 is connected to a mounting base (not shown) previously installed on the ceiling surface, and the smoke sensor Three connecting fittings 17 are provided for fixing 10 to the ceiling surface (one of them is visible in FIG. 1). Further, the body case 11 is provided with three boss portions 11b through which screws 18 for fixing the circuit board 13 and the dark box base 14 housed in the housing recess 11A are inserted (one of these boss portions 11b in FIG. 1). individual is visible). Further, the outer peripheral wall of the main body case 11 is provided with an engaging portion 11c with which the claw portion at the tip of the locking claw 12d (see FIG. 3) of the outer cover 12 is engaged.

The dark box base 14 is provided with a storage portion 14a for storing a light emitting element 19A such as an LED (light emitting diode) that emits red light, and a storage portion 14b for storing a light receiving element 19B such as a photodiode. Holes (not shown) through which the lead terminals 19a and 19b of the light emitting element 19A and the light receiving element 19B can be inserted are formed in the bottom walls of the portions 14a and 14b. The tip of the lead terminal of the element passes through the circuit board 13 and is connected by flow soldering or the like. Further, the dark box base 14 is provided with a rib 14e which is circular in top view and fits in the central opening 12A of the outer cover 12. As shown in FIG.

Further, the dark box base 14 is provided with two locking pieces (hooks) 14c projecting toward the circuit board 13 side (downward in the drawing), and the tips of these locking pieces 14c are attached to the circuit board 13. The dark box base 14 and the circuit board 13 are configured to be integrated by engaging with the formed engagement hole 13c. The circuit board 13 is composed of a printed wiring board on which electronic components such as resistors, capacitors, and ICs (semiconductor integrated circuits) constituting an electronic circuit for fire detection are mounted on the upper and lower surfaces, and screws are inserted into the board. Three holes 13a are formed in the body case 11, and the body case 11 is secured by screws 18 inserted through the screw holes 17 of the connecting fittings 17 and the boss portion 11b of the bottom wall of the body case 11 and into the screw insertion holes 13a of the circuit board 13. It is fixed in the housing recess 11A (see FIGS. 1 and 2).

The light-receiving element 19B is configured to be housed in an electromagnetic shielding case 20 made of a conductive material and inserted into the housing portion 14b. Also, the dark box cover 16 is provided with light shielding walls 16a and 16b formed so as to surround the elements housed inside corresponding to the housing portions 14a and 14b of the dark box base 14. As shown in FIG. The light shielding walls 16a and 16b may be provided on the dark box base 14 side.
On the other hand, the outer cover 12 has a circular opening 12A at the center thereof through which the upper part of the dark box can protrude. A disk-shaped head portion 21 engaged with the edge portion is provided, and an opening 22 communicating with the opening portion 12A is formed between the head portion 21 and the upper wall of the body portion of the outer cover 12 in the circumferential direction. , and the openings 22 function as smoke inlets that allow smoke from the outside to flow into the case.

A ring-shaped light emitting member 23 made of a transparent material such as acrylic resin is fitted to the edge of the opening 12A at the center of the outer cover 12. As shown in FIG. A pair of rod-shaped light guide portions 23a formed so as to hang down is coupled to the light emitting member 23, and one tip (lower end) of the light guide portions 23a guides light. An incident portion (end face) is configured to face a light emitting diode (LED) (not shown) mounted on the circuit board 13 for informing the operating state. Further, although not shown, a plurality of small projections are formed on the outer surface of the ring-shaped light emitting member 23, and the light emitting member is accommodated near the opening 12A of the outer cover 12 that contacts the outer surface of the light emitting member 23. Holes are formed on the inner surface of the portion at positions corresponding to the protrusions, and the protrusions are engaged with the holes so that the light emitting member 23 is locked inside the opening 12A of the outer cover 12. configured to be

FIG. 3 is a perspective view of the outer cover 12 constituting the sensor of FIG. 1, which is turned upside down and viewed obliquely from above. As shown in FIG. 3, the outer edge of the outer cover 12 is provided with an outer rib 12a extending upward (downward in FIG. 1), and at a position slightly away from the open end of the opening 12A of the outer cover 12. An inner rib 12b is provided to stand upward (downward in FIG. 1), and an annular recess is formed between the outer rib 12a and the inner rib 12b. A part of the outer rib 12a is cut out to form four drain holes 12c at approximately 90° intervals.
Further, in the vicinity of the opening 12A of the outer cover 12, two through holes 12i are formed through which the two light guide portions 23a provided on the ring-shaped light emitting member 23 are inserted. A drain hole 12h is formed at a portion closer to the opening 12A than the inner rib 12b.

Further, at a position which is substantially the same radial position as the inner rib 12b and which is slightly closer to the center side, there is a height sufficiently higher than the height of the inner rib 12b, and the outer peripheral wall of the main body case 11 is engaged. Engagement claws 12d that can be engaged with the portion 11c (three locations) are formed at three locations at intervals of approximately 120°. Notches 12e (three places) having a width slightly wider than the width of 12d are respectively formed.

On the other hand, as shown in FIG. 1, three engaging portions 11c are formed on the upper portion of the peripheral surface of the outer peripheral wall of the main body case 11, and the engaging portions 11c are formed at positions slightly below the upper end in the outer peripheral direction. A protruding ring-shaped rib 11d is formed. When the outer cover 12 is attached to the main body case 11, the locking claws 12d of the outer cover 12 and the engaging portions 11c of the main body case 11 are integrated with each other, and the lower surfaces of the ribs 11d are attached to the outer cover 12 as described above. The height of the rib 11d is set so as to contact the upper end surface of the inner rib 12b.

Next, a device for harmonizing the surface-side parts and visible parts of the smoke sensor with the environment, which is the gist of the present invention, will be described.
The most visually conspicuous part of a conventional general smoke sensor is the outer peripheral surface of the insect screen 15 facing the opening 22, which is the smoke inlet. In addition, the upper surface and the inner peripheral surface of the rib 14e for fitting the outer cover 12 provided on the dark box base 14, the part of the light shielding wall 14d of the labyrinth structure with which the inner surface of the insect screen 15 contacts, and the ring-shaped light emission. There is an exposed surface of the member 23 and the like. Of these ribs 14e, the fitting rib 14e is formed with a tapered surface that slopes downward toward the center inside the upper end so that smoke can easily flow into the smoke inlet (opening 22) of the outer cover 12 from the outside. Therefore, the material color (dark color) of the tapered surface was conspicuous when the smoke detector was viewed obliquely from below.

Therefore, in the smoke sensor of the present embodiment, the outer peripheral surface of the insect screen 15 is coated with the same color (generally white) as the surface of the outer cover 12 to make it inconspicuous. Further, instead of applying paint to the outer peripheral surface of the insect screen 15, the insect screen 15 may be formed of a resin having the same color as the surface of the outer cover 12. Since the insect screen 15 is relatively thin, a metal mesh is generally used. is also described.

Next, with respect to the ribs 14e for fitting the outer cover 12 provided on the dark box base 14, the upper surface and the inner peripheral surface (tapered surface) on the dark box side are coated with the same color as the surface of the outer cover 12. It was decided to. When the sensor in the installed state is viewed from directly below, the rib 14e overlaps with the head portion 21 of the outer cover 12 and is almost invisible. These areas should be the same color as the outer cover in order to be visible. For this reason, the upper surface of the rib and the inner peripheral surface (tapered surface) may be coated with paint having the same color as the surface of the outer cover 12 .
The dark box base 14 is made of black resin in order to prevent light from the outside from reaching the light-receiving element of the photoelectric smoke sensor housed inside due to irregular reflection on the surface of the light-shielding wall. There are many. Therefore, it is not desirable to form the dark box base 14 itself with resin of the same color as the surface of the outer cover 12, and the paint is applied to the upper surface of the rib 14e for fitting the outer cover 12 outside the smoke detection area and the upper surface of the outer cover 12. It is better to stay on the inner peripheral surface (tapered surface).
A portion of the light shielding wall 14d having a labyrinth structure that is in contact with the inner surface of the insect screen 15 (dotted portion in FIG. 1) is also coated with the same color as the surface of the outer cover 12. FIG. If the light shielding wall 14d is black, the inner light shielding wall 14d is conspicuous through the insect screen 15 whose outer peripheral surface is white.

If a white paint is applied to the surface of the light shielding wall 14d that is in contact with the insect net, the dark box base 14 is made of black resin to prevent external light from reaching the internal light receiving element. Although there is a possibility that the dark box base 14 will be damaged, the dark box base 14 is nearly black in order to be able to test whether the light receiving element operates normally by utilizing a slight amount of light leaking in from the outside in the initial inspection. There is a design method of forming with gray resin. Therefore, although there is no particular problem in applying white paint to a part of the surface (outermost surface) of the light shielding wall 14d in contact with the insect screen, the coating area of the paint becomes wider ( Since the function of the dark box base 14 will be impaired if it is spread outside the surface (outermost surface), the coating range should be appropriately set in relation to the color of the resin of the dark box base 14 and the labyrinth structure.

On the other hand, with respect to the light emitting member 23, the main body case 11 and the outer cover 12 are generally made of white resin or white resin so that the sensor does not stand out when installed on the white ceiling surface of a building. On the other hand, the ring-shaped light emitting member 23 is made of a transparent material as described above. Since the surface color of the cover 12 is different, the light emitting member 23 is conspicuous.
Therefore, in the smoke sensor of this embodiment, an opaque paint having the same color as the surface of the outer cover 12 is applied only to the exposed surface (upper surface) of the light emitting member 23, as shown in FIG. , a thin coating 23b is formed.

The film 23b is opaque, but when the LED on the circuit board 13 is turned on and the light is guided from the light guide portion 23a to the light emitting member 23, it leaks to the surface side of the outer cover 12 and shines brightly. is formed so that Therefore, it is desirable to form the film 23b as thin as possible. However, if the thickness of the coating 23b is made thin, it becomes easy to peel off, so the thickness should be determined in consideration of the balance between the amount of light transmitted and the durability.

In the above description, an example in which the light emitting member has a ring shape that is highly visible from all directions of 360 degrees has been described. By forming a film of the same color as the cover, the smoke sensor can be constructed so that it is easy to see when the operation indicator light is illuminated and is inconspicuous with the same color as the outer cover when the operation indicator light is not operating.
Further, the spot-shaped operation indicator lamp may be formed of a bullet-shaped LED, and the surface side of the outer cover of the operation indicator lamp may be coated with the same color as the outer cover.
Alternatively, the coating 23b may be formed on the surface of the light emitting member 23 and the outer cover 12 itself may be made of a material that allows light to pass through to some extent. It should be noted that although it is a heat sensor, it is possible to form the cover of the sensor with a resin that allows light to pass through so that the lighting state of the LED arranged inside can be visually recognized. is also described.

As described above, in the smoke sensor of the present embodiment, the thin film 23b made of paint or the like is formed on the surface of the light emitting member 23, so that the light emitting member 23 is prevented from becoming conspicuous. can be done. In addition, since the outer peripheral surface of the insect screen 15 is coated with paint of the same color (generally white) as the surface of the outer cover 12, or the insect screen 15 is formed of resin of the same color as the surface of the outer cover 12, It is possible to prevent the insect screen 15 from being conspicuous.
Furthermore, since the upper surface and the inner peripheral surface of the rib 14e for fitting the outer cover 12 of the dark box base 14 are coated with the same color as the surface of the outer cover 12, the rib 14e is partially conspicuous. can be prevented.

In the above embodiment, the surface of the light emitting member 23, the outer peripheral surface of the insect screen 15, and the upper surface and inner peripheral surface of the rib 14e for fitting the outer cover 12 of the dark box base 14 are colored in the same color as the surface of the outer cover 12. Of these, the insect screen 15 and the dark box base 14 are provided at a location inside the outer cover 12 where external light is difficult to reach. The upper surface of 14e and the inner peripheral surface on the side of the dark box may be made brighter than the surface of the light emitting member 23. FIG. As a result, the surface of the insect screen 15 and the ribs 14e of the dark box base 14 can be made inconspicuous even when the smoke sensor is installed on the ceiling surface of a building or the like.
Further, in the above description, an example in which the film is formed by applying paint has been described, but the same effect can be obtained by forming the film by pasting a seal.
Furthermore, by individually implementing the examples described above, it is possible to reduce the portions (areas) that do not fit in with the color of the installation environment.

(Second embodiment)
5 to 7 show a second embodiment of the smoke detector according to the invention.
In the smoke sensor of the second embodiment, as shown in FIG. 5, a ring-shaped light emitting member 23 is arranged on the lower side when the outer cover 12 is installed. 23 is covered with the outer cover 12 so that the ring-shaped light emitting member 23 is not directly visible from the outside, and the thickness of the portion of the outer cover 12 facing the upper surface of the ring-shaped light emitting member 23 is set to another value. A thin portion 12f made thinner than the thickness of the portion is provided.
As a result, the ring-shaped light emitting member 23 is completely invisible from the outside when the operation indicator lamp (LED) is not lit, and the light from the LED is guided to the ring-shaped light emitting member 23 when the operation indicator lamp is illuminated. , light is emitted from the surface, and the light is transmitted through the thin portion of the outer cover 12, and the surface of the outer cover 12 becomes bright in a ring shape so that the lighting state of the operation indicator lamp can be visually recognized. become.

It is the same as the first embodiment except that the light emitting member 23 is arranged under the outer cover 12, and the outer peripheral surface of the insect screen 15 is coated with the same color paint as the surface of the outer cover 12, or An insect screen 15 is made of resin having the same color as the surface of the outer cover 12 . Further, the inner peripheral surface (inner surface and tapered surface) of the outer cover 12 fitting rib 14e provided on the dark box base 14 on the dark box side is coated with the same color as the outer cover 12 surface. Further, a portion of the light shielding wall 14d having a labyrinth structure, which is in contact with the inner surface of the insect screen 15, is also coated with the same color as the surface of the outer cover 12. As shown in FIG.

The ring-shaped light emitting member 23 has a plurality of small protrusions formed on the outer surface thereof, and is attached to the inner surface of the light emitting member storage portion near the opening 12A of the outer cover 12, which is in contact with the outer surface of the light emitting member 23. is formed with a hole at a position corresponding to the projection, and the projection engages with the hole so that the light emitting member 23 is locked inside the opening 12A of the outer cover 12. It is A plurality of small protrusions are formed on the inner surface of the light emitting member 23, and pores are formed at positions corresponding to the protrusions on the outer surface of the ribs 14e of the dark box base 14 that are in contact with the inner surface of the light emitting member 23. Alternatively, the light emitting member 23 may be engaged with the outer side of the rib 14e of the dark box base 14 by engaging the protrusion with the hole.

Next, the specific structure of the portion of the outer cover 12 that covers the light emitting member 23 and faces the upper surface of the light emitting member 23 will be described with reference to FIGS. 6(A) to 6(C). 6A to 6C are enlarged cross-sectional views of the engaging claw forming portion of the outer cover 12, the column forming portion of the smoke inlet, and other portions, respectively.

As shown in FIG. 6A, the outer cover 12 has a thin portion 12f on the inner side (left side in FIG. 6) of the locking claw 12d. A rib R is provided at the end of the thin portion 12f, and a drain hole 12j is formed by cutting out a portion of the rib. By doing so, the drain holes 12j are not visible from below and can be made inconspicuous.
In addition, as shown in FIG. 6B, the part where the pillar 12g of the smoke inlet (22) of the outer cover 12 is provided is the inner side (left side in FIG. 6) and the outer side of the rib 12b of the outer cover 12. are formed to have the same thickness. As shown in FIG. 6(C), portions other than those shown in FIGS. 6(A) and (B) are provided with thin portions 12f.

Since the thin portion 12f is provided in the portion of the outer cover 12 facing the upper surface of the light emitting member 23 as described above, the light emitted from the light emitting member 23 is transmitted through the thin portion 12f. Even if the surface of the cover 12 shines brightly and the light emitting member 23 is covered with the outer cover 12, the visibility of the operation indicator lamp hardly deteriorates.
Further, it is assumed that the strength of the base portion of the column supporting the outer cover 12, particularly the head portion 21, is reduced by providing the thin portion 12f in the vicinity of the opening portion 12A of the outer cover 12 as described above. In terms of form, as shown in FIG. 6(B), since the outer cover 12 is not provided with a thin portion 12f in the vicinity of the column forming portion of the smoke inlet, when an external force acts on the head portion 21, the smoke inlet is closed. It is possible to suppress the deterioration of the strength of the base portion and the head portion 21 of the column 12g.
On the other hand, when considering the installation mode of the outer cover 12 (installation on the ceiling where it is difficult to reach), the slight decrease in strength is negligible, so the thin portion 12f is formed continuously along the ring-shaped light emitting member 23. By doing so, a continuous ring display can be performed.

FIG. 7 shows the appearance of the smoke sensor of the second embodiment installed on the ceiling as viewed obliquely from below. In FIG. 7, the hatched portion corresponds to the thin portion 12f of the outer cover 12, and when the internal LED is turned on, the light is guided to the inner ring-shaped light emitting member 23. , the hatched area shines brightly evenly. Therefore, although the example of FIG. 7 has a slightly interrupted portion, it functions as an operation indicator light that lights up in a ring shape. Visibility from any direction is good.

Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments.
It suffices if the luminescence can be visually observed from the surface of the outer cover when the operation indicator lamp of the smoke sensor is activated (when it emits light). It is sufficient that the thickness is such that light can be transmitted to the outside of the outer cover. As one example, the entire outer cover member 12 of Example 2 is formed with a thickness equivalent to that of the thin portion, and the ring display of the operation indicator lamp is made clearer and the strength of the outer cover is increased. A second outer cover is placed only on the outside of the lamp (in the direction away from the sensor), and by reducing the amount of transmitted light on the outside of the operation indicator lamp (in the direction away from the sensor), the display state is clearer when viewed visually. It is possible to display the shape and ensure the strength of the outer cover.
In the above embodiment, four pillars 12g forming the opening 22 as the smoke inlet of the outer cover 12 are shown. good.
Furthermore, in the above-described embodiment, the light emitting surface (indication lamp) of the light emitting member 23 is shown to be circular, but it may not be circular, and may be oval, star-shaped or flower-shaped with a plurality of bends. It may have a shape such as

(Other embodiments)
In the smoke sensor of the first embodiment and the second embodiment, the configuration in which the operation indicator lamp can be confirmed from the surface side of the outer cover 12 (the side that can be visually observed in the installed state) has been described.
Next, an example of a structure other than the first and second embodiments, which is inconspicuous when the operation indicator lamp is not operated and improves visibility when the operation indicator lamp is operated, will be described with reference to FIG.
In the example shown in FIG. 8, the basic structure is similar to that of the second embodiment, but the rib 14e is formed separately from the dark box base 14 instead of integrally formed, and is fitted in the same position as the rib formation position in FIG. It differs in that it is configured to be fixed and that the separate rib 14e is made of a material having optical transparency.

By changing the two points described above with respect to the structure of the smoke sensor of the second embodiment, the light emitted from the light emitting member 23 is transmitted through the light-transmitting rib 14e to an insect net (the surface is outside). The surface of the cover 12 and the same color) 15 can be irradiated with the light from the light emitting member 23 to display the operation of the operation indicator lamp on the surface of the insect screen. As a result, the appearance can be unified to the color of the outer cover when the operation indicator lamp is not in operation, and by matching the color of the outer cover to the color of the installation environment, it is possible to realize a smoke detector that is in harmony with the environment. can. The upper surface and the inner peripheral surface (tapered surface) of the rib 14e are coated with paint having the same color as the surface of the outer cover 12. As shown in FIG.

In the example of FIG. 8, both the projection display on the surface of the insect screen and the transmission display from the portion (thin portion) of the outer cover 12 overlapping the light emitting member 23 in the smoke sensor of the second embodiment can be performed. Although the structure is shown, it may be configured to implement only a light projection display on the surface of the insect screen, thereby making it inconspicuous when the operation indicator light is not activated and making it visible when the operation indicator light is activated. It can serve the function of making good.
In the example of FIG. 8, a ring-shaped light emitting member 23 is arranged under the outer cover 12, which cannot be visually recognized from the outside, and light is projected from the ring-shaped light emitting member 23 onto the surface of the insect screen 15 through the ribs 14e. Although an example has been described, it is not limited to such a configuration. As long as the light emitted from the ring-shaped light emitting member 23 can be projected onto the surface of the insect screen 15, it is sufficient for a smoke sensor having a structure in which the dark box base 14 does not require the ribs 14e. It is sufficient that the light projection path from the member 23 to the surface of the insect screen is sufficiently secured. Also, the ring-shaped light emitting part 23 may be arranged inside the opening part 12A. It is good if it is arranged.

10 fire detector (photoelectric smoke detector)
11 Body Case 11c Engaging Portion 11d Rib 12 Outer Cover (Cover Member)
12A opening 12b inner rib 12d locking claw (locking means)
12f thin portion 12g pillar forming smoke inlet 13 circuit board 14 dark box base 14d light shielding wall 14e rib 15 insect net 16 dark box cover 19A light emitting element 19B light receiving element 21 head portion of outer cover 22 opening (smoke inlet)
23 light emitting member 23b coating (coating film)

Claims (9)

A sensing unit equipped with a photoelectric smoke sensor and an electronic circuit for detecting the occurrence of a fire based on a signal from the sensing unit are placed inside a housing composed of a main body and a cover member covering the upper side of the main body. A smoke sensor containing a mounted circuit board and equipped with an insect screen visible from the outside,
The cover member is provided with a cover body portion having an opening facing the sensing portion, a head portion covering the sensing portion, and a plurality of pillars connecting the head portion and the cover body portion, A smoke inlet is formed between each of the pillars,
a light emitting member having a light emitting portion that constitutes an operation indicator lamp, the light emitting member being disposed so that the light emitting portion faces the surface side of the cover member;
A smoke sensor, comprising: an opaque coating layer having the same color as the surface color of the cover member, the opaque coating layer allowing light to leak so as to cover the light emitting part. 2. The smoke sensor of claim 1, wherein said operation indicator light is annular and positioned adjacent said opening in said cover member and outside said post. 3. The smoke sensor according to claim 1, wherein said coating layer is a coating formed on the exposed side surface of said light emitting portion. the light emitting member is disposed inside the cover member;
3. The smoke sensor according to claim 1, wherein the covering layer is formed on a portion of the cover member facing the light emitting portion. 5. The smoke sensor according to claim 4, wherein the portion is a thin-walled portion and is formed in a portion excluding at least the vicinity of the plurality of pillars. The housing contains the insect screen facing the smoke inlet and disposed so as to surround the sensing unit,
2. The insect screen is formed on its outer surface with a layer having the same color as the surface color of the cover member, or is entirely made of resin having the same color as the surface color of the cover member. 6. The smoke sensor according to any one of 1 to 5. The sensing unit includes a dark box containing the photoelectric smoke sensor and a dark box base for holding the dark box. The dark box has a storage space inside for storing the photoelectric smoke sensor and an outside of the storage space. A light-shielding wall with a labyrinth structure is provided in
7. A smoke sensor according to claim 6, wherein at least a portion of said light shielding wall which is in contact with said insect net is colored in a similar color to the surface color of said cover member. The dark box base is provided with a rib that allows the opening of the cover member to be fitted to the outside,
8. The smoke sensor according to claim 7, wherein the upper surface of the rib and a part of the inner peripheral surface of the rib on the side of the dark box are colored in the same color as the surface color of the cover member. 7. A smoke sensor according to claim 6, wherein a space serving as a light projection path or a light-transmitting member is provided between said light emitting portion and said insect screen.

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