TWI438722B - Fire alarm device - Google Patents

Description

Fire alarm

The present invention relates to a fire alarm that integrally includes a sensor unit and an alarm unit.

A conventional fire alarm is provided inside a flat box type body: a sensor unit for detecting a fire, and an alarm unit for issuing an alarm when the sensor unit detects a fire. Further, the dark box of the sensor unit and the acoustic member of the alarm unit are disposed inside the main body without overlapping (see, for example, Patent Document 1).

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2004-362537

However, in the conventional fire alarm, since the dark box and the acoustic member are disposed so as not to overlap each other, the casing becomes large in diameter, which causes inconvenience in handling, and becomes conspicuous when installed on the ceiling, thereby damaging the appearance of the room. Therefore, it is conceivable to arrange a part of the acoustic member so as to overlap the dark box on the back side of the dark box. However, a part of the alarm sound from the acoustic member is diffused inside the casing after hitting the back of the black box, and there is a problem that the predetermined sound pressure cannot be secured.

The present invention has been made in order to solve the above problems, and an object thereof is to obtain a fire alarm that can reduce the diameter of a casing and increase the sound pressure of an alarm sound.

The fire alarm of the present invention includes a black box storage unit (a tobacco inflow window is formed to protrude toward the front surface), and an acoustic member housing portion (an acoustic hole is formed outside the dark box housing portion). a cover, a dark box housed in the dark box storage unit, an acoustic member housed in the acoustic member storage unit, a printed circuit board disposed on a back side of the dark box, and a fixed dark box and the acoustic member between the cover and the protective cover The main body of the printed circuit board; the fire alarm device is characterized in that the acoustic member is superposed on the back side of the dark box; and the protective cover is provided on the back side from the side of the acoustic member that does not overlap the dark box a first rib that contacts the edge portion; and a second rib that surrounds the outer periphery of the acoustic member that overlaps the dark box is provided on the back side of the dark box.

The fire alarm according to the present invention can exert the following effects. By arranging the acoustic member and the black box in a partially overlapping manner in the housing, the diameter of the housing can be reduced, and the first rib and the second rib can provide an alarm sound from the acoustic member without damaging the sound pressure. The sound is emitted to the outside of the front side of the fire alarm, so that an alarm sound of a predetermined sound pressure can be emitted.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the fire alarm of the present invention will be described with reference to the drawings. In the following description, the side attached to the ceiling or the like is referred to as the back side, and the side opposite to the back side is referred to as the front side. Further, a direction parallel to the ceiling or the like is referred to as a horizontal direction.

Fig. 1 is a plan view showing a state in which the mount and the body of the fire alarm of the present invention are removed. Fig. 2 is a cross-sectional view of the fire alarm of section A-A of Fig. 1. Figure 3 is a top view of the protective cover of the fire alarm. Fig. 4 is a plan view of a black box, a printed circuit board, and a speaker of a fire alarm. Fig. 5 is a plan view seen from the body side of the fire alarm. Fig. 6 is a cross-sectional view of a section B-B of Fig. 5.

The fire alarm 1 of the present invention has a circular shape and allows smoke to flow in from the center. The fire alarm device 1 of the present invention includes a dark box storage unit 3 having a built-in hidden box 2 (projecting in a cylindrical shape toward the front side in the center portion) and an acoustic member housing portion 5 (outside the horizontal direction of the dark box housing portion 3) a protective cover 6 through which the acoustic hole 4) is inserted, a dark box 2 housed in the dark box housing portion 3 of the protective cover 6, a printed circuit board 7 disposed on the back side of the dark box 2, and an acoustic member disposed on the acoustic member housing portion 5 (speaker 8) The main body 16 for arranging the dark case 2, the printed circuit board 7, and the speaker 8 and the mounting seat (not shown) disposed on the back side of the main body 16 are disposed on the back side of the protective cover 6. Further, the protective cover 6, the body 16, and the mount are collectively referred to as a frame.

The black box 2 has a cylindrical shape and allows smoke to invade from the side to detect the occurrence of smoke. Further, as shown in FIG. 2, the dark case 2 is mounted on the printed circuit board 7 in a non-contact manner, and by this structure, wafer-shaped electrical components can be mounted on both surfaces of the printed circuit board 7 (not shown). ).

The dark box accommodating portion 3 is provided with a smoke inflow window 9 on the side surface of the cylindrical shape, and the smoke flowing in from the smoke inflow window 9 flows into the dark box 2 from the side surface of the dark box 2.

The acoustic member accommodating portion 5 is provided with an acoustic hole 4 in a specific region of the protective cover 6, that is, a portion of the speaker 8 that faces the disc-shaped speaker 8 that does not overlap the bottom surface of the dark box accommodating portion 3. When the speaker 8 is disposed in the acoustic member housing portion 5, the distance between the center of the speaker 8 and the center of the bottom surface of the dark box housing portion 3 is smaller than the sum of the radius of the speaker 8 and the radius of the bottom surface of the dark box housing portion 3, and the acoustic hole 4 is The wearing region is a shape in which a part of the circle of the speaker 8 is cut off by the bottom surface of the dark box housing portion 3.

In the periphery of the region around which the acoustic hole 4 is disposed, the periphery that does not overlap the dark box storage portion 3 has an arc shape, and an arc-shaped positioning rib 10 is provided on the outer side of the periphery to provide the speaker 8 with the sound. When the component housing portion 5 is used, the lateral movement of the speaker 8 is restricted. Further, when the speaker 8 is disposed in the acoustic member accommodating portion 5, if the speaker 8 moves slightly on the plane, the outer circumference of the speaker 8 hits the positioning rib 10 to prevent further movement.

Inside the positioning rib 10, an arc-shaped first rib 12 that abuts against the outer edge portion 11 of the speaker 8 is provided. When the speaker 8 is placed in the acoustic member housing portion 5, the top of the first rib 12 abuts against a portion of the outer edge portion 11 of the speaker 8, and the sound wave from the speaker 8 is prevented from being between the speaker 8 and the positioning rib 10. leakage.

The outer circumference of the acoustic member accommodating portion 5 that is in contact with the dark box accommodating portion 3 is an arc shape that protrudes toward the center of the speaker 8 (when the speaker 8 is placed in the acoustic member accommodating portion 5). An arc portion 14 is erected on the protruding arc. The arc portion 14 has a shape that forms a bank that overlaps the speaker 8 along the dark box housing portion 3 and is coupled to both ends of the first rib 12 . The height of the top of the arc portion 14 is lower than the top of the first rib 12, and a gap can be secured between the speaker 8 and the arc portion 14 when the speaker 8 is placed in the acoustic member housing portion 5. The portion of the speaker 8 facing the top of the arc portion 14 vibrates, and if the speaker 8 is in contact with the arc portion 14, the sound pressure is lowered. By keeping a slight gap, the sound propagating from the front chamber surrounded by the protective cover 6 and the first rib 12 to the dark box accommodating portion 3 is reflected by the curved portion 14, and can be returned to the front chamber and transmitted from the acoustic hole 4. Out.

The second rib 13 having an arc shape is provided on the bottom surface of the back side of the dark box 2, and the second rib 13 is provided on an arc on which the positioning rib 10 is externally inserted when the dark box 2 is housed in the dark box accommodating portion 3. The height of the second rib 13 is substantially in contact with the printed circuit board 7. The sound wave radiated from the portion of the speaker 8 facing the bottom surface on the back side of the dark box 2 is reflected by the second rib 13, and then propagates toward the front side from the side surface of the dark box 2 through the smoke inflow window 9.

The second rib 13 is disposed to surround the outer circumference of the speaker 8 . Here, the second rib 13 may be disposed to abut against the outer edge portion 11 of the speaker 8. In this case, the smoke detecting element (not shown) in the dark box 2 is vibrated by the speaker 8. Peeling may occur with the welded portion of the printed substrate 7.

The acoustic member holding rib 15 is provided on the front side of the main body 16, and when the main body 16 is attached to the protective cover 6 by screwing as shown in Fig. 5, it will abut against the back side of the speaker 8 as shown in Fig. 6. The outer edge portion 11 holds and holds the speaker 8 between it and the first rib portion 12. The acoustic member holding rib 15 has a substantially cylindrical shape having a diameter substantially the same as that of the first rib 12, and is abutted against the outer edge portion 11 of the speaker 8 by a plurality of abutting portions 15a provided at the distal end.

From the front view, the speaker 8 and the black box 2 are partially overlapped to each other, and the frame body is reduced in diameter. The speaker 8 is positioned by the positioning rib 10 provided on the protective cover 6 and the second rib 13 provided in the dark box 2.

The sound generated in the horizontal direction from the front side portion of the speaker 8 facing the acoustic hole 4 is blocked by the first rib 12 without being diffused into the inside of the casing, so that the sound can be emitted from the acoustic hole 4 in the straight forward direction. . Further, the alarm sound generated from the portion facing the front side of the speaker 8 of the black box 2 is reflected by the second rib 13 and then released from the side surface of the dark box 2 through the smoke inflow window 9 to the outside of the fire alarm 1.

In this manner, the first rib 12 and the second rib 13 allow the alarm sound from the speaker 8 to emit sound to the outside of the front side of the fire alarm 1 without damaging the sound pressure, so that a predetermined sound pressure can be emitted. Alarm tone. In particular, an alarm sound generated from a portion facing the front side of the speaker 8 of the black box 2 is sounded by the second rib 13 along the side of the dark box 2 from the smoke inflow window 9, whereby an alarm occurs from the speaker 8. All of the sounds can be emitted to the outside of the fire alarm 1 through the protective cover 6 in a substantially straight forward direction, so that the sound pressure loss of the alarm sound can be further reduced.

The alarm sound generated from the portion facing the front side of the speaker 8 of the acoustic hole 4 is almost entirely discharged from the acoustic hole 4 by the arc portion 14, and on the other hand, from the front side of the speaker 8 facing the dark box 2. The partially generated alarm sound also emits sound almost from the smoke inflow window 9 by the arc portion 14, so that the alarm sound is emitted through the protective cover 6 in a substantially straight forward direction, so that the sound of the alarm sound can be further reduced. Pressure loss.

Since the height of the arc portion 14 is lower than that of the first rib portion 12, vibration occurs even when the speaker 8 emits sound, and the diaphragm of the speaker 8 does not contact the arc portion 14, so that the frame body does not cause chattering sound.

1. . . Fire alarm

2. . . Black box

3. . . Black box storage

4. . . Acoustic hole

5. . . Acoustic component storage unit

6. . . protection cap

7. . . Printed substrate

8. . . speaker

9. . . Smoke into the window

10. . . Positioning rib

11. . . Outer edge

12. . . First rib

13. . . Second rib

14. . . Arc

15. . . Acoustic member retaining rib

15a. . . Abutment

16. . . Ontology

Fig. 1 is a plan view showing a state in which the mount and the body of the fire alarm of the present invention are removed.

Fig. 2 is a cross-sectional view of the fire alarm of section A-A of Fig. 1.

Figure 3 is a top view of the protective cover of the fire alarm.

Fig. 4 is a plan view of a black box, a printed circuit board, and a speaker of a fire alarm.

Fig. 5 is a plan view seen from the body side of the fire alarm.

Fig. 6 is a cross-sectional view of a section B-B of Fig. 5.

1. . . Fire alarm

2. . . Black box

6. . . protection cap

7. . . Printed substrate

8. . . speaker

10. . . Positioning rib

13. . . Second rib

Claims (3)

A fire alarm device includes a protective cover having a dark box accommodating portion (a tobacco inflow window is formed to protrude toward the front surface), and an acoustic member accommodating portion (an acoustic hole is formed outside the dark box accommodating portion), a dark box housed in the dark box accommodating portion, an acoustic member housed in the acoustic member accommodating portion, a printed circuit board disposed on a back side of the dark box, and a dark box and the acoustic member and the printing between the protective cover and the protective cover The main body of the substrate; the fire alarm device is characterized in that the acoustic member is superposed on the back side of the dark box; and the protective cover is provided on the back side from an outer edge portion of the acoustic member that does not overlap the dark box a first rib that contacts the first rib; and a second rib that surrounds an outer circumference of the acoustic member that overlaps the dark box. The fire alarm according to the first aspect of the invention, wherein the protective cover is provided with an arc portion that is connected to both ends of the first rib along a bank that overlaps the acoustic member in the dark box housing portion . The fire alarm according to the second aspect of the invention, wherein the arc portion has a lower height than the first rib.