JP7818123B2 - Alarm bell - Google Patents

Description

This invention relates to an alarm bell that sounds an alarm by striking a gong.

An alarm bell comprises a gong that produces a bell sound when struck, a striker that strikes the gong, a motor that drives the striker, and a housing that houses the motor. In the event of an emergency such as a fire, the gong sounds, producing a bell sound and issuing an alarm (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2000-235394

The main uses of this type of alarm bell are as local sounding devices in automatic fire alarm systems and emergency bells in emergency alarm systems (hereinafter simply referred to as "emergency bells").

Standards for emergency bells are set in accordance with the Fire Service Act. One of those standards is sound pressure (90 dB or more at a distance of 1 m from the center).

Emergency bells are sometimes installed inside a housing such as a fire hydrant box or equipment storage box. In such cases, they still need to meet the sound pressure standards mentioned above, but being housed inside a housing can reduce the sound pressure, making it difficult to achieve the required sound pressure.

In consideration of the above circumstances, this invention aims to provide an alarm bell that can increase sound pressure.

This invention relates to an alarm bell that sounds an alarm when struck by a gong, and includes a cylindrical hood that surrounds the gong. The alarm bell also includes a mounting part for attaching the gong to an object to which it is attached. The hood is attached to the object together with the gong via the mounting part. The mounting part has a base plate and a detachable part that is provided on the base plate and detachably connected to it. When the alarm bell is to be installed without the hood, the detachable part can be detached from the mounting part and used as a part for attaching the gong to the object to which it is attached.

In this invention, the mounting part may be plate-shaped.

In this invention, the gong can be surrounded by a hood. This hood prevents the bell sound from diffusing around the gong, strengthening its directionality and increasing its sound pressure.

Therefore, this invention provides an alarm bell that can increase sound pressure.

When conventional alarm bells are installed inside a housing, as mentioned above, the housing reduces the sound pressure, making it difficult to obtain the required sound pressure. However, with this invention, even when the bell is installed inside a housing, the sound pressure can be increased by providing a hood, so the sound pressure does not decrease as it does with conventional alarm bells. In other words, this invention is particularly suitable for alarm bells that are installed inside a housing, and the inclusion of a hood offers significant advantages.

1A and 1B show an example of an embodiment of the alarm bell of the present invention, in which (a) is a front view and (b) is a perspective view showing the entire alarm bell with the hood attached to the mounting bracket surrounding the gong. 1A is a front view of the same gong, and FIG. 1B is a rear view of the same gong. 1A is a front view of the hood attached to the mounting bracket, and FIG. 1B is a side view of the hood attached to the mounting bracket. 4A and 4B are a perspective view and a side view, respectively, of components constituting the hood of the same as above. FIG. FIG. 2 is a front view of the equipment housing box to which the alarm bell is attached. This is an enlarged cross-sectional view of a portion (the portion on the alarm bell side) of the line AA in Figure 6. However, wall panel portions (such as the back panel) other than the front panel of the equipment housing box are not shown. FIG. 10 is a front view of another example of a mounting bracket.

An example of an embodiment of the alarm bell of this invention will be described below as alarm bell 1, with reference to Figures 1 to 8. Note that alarm bell 1 can be used, for example, as a district sounding device in an automatic fire alarm system or as an emergency bell in an acoustic device in an emergency alarm system.

[Basic configuration]
2, the alarm bell 1 is equipped with a gong 2 that rings when struck and is used to sound an alarm in the event of an emergency such as a fire. The back side of the gong 2 is provided with a housing 4 that supports a striking rod 3 that strikes the gong 2 and houses a drive mechanism (not shown) for driving the striking rod 3. The housing 4 is provided with a hook 4a for attaching the gong 2 to mounting brackets 6 and 7 (examples of mounting parts) that will be described later.

[Food]
The alarm bell 1 is particularly suited for use when it is housed and installed inside a housing such as a fire hydrant box or an equipment housing box (specific examples of which will be described later), and as shown in FIG. 1, it is provided with a cylindrical hood 5 that surrounds the gong 2.

In the alarm bell 1, the gong 2 can be surrounded by a hood 5. The hood 5 prevents the bell sound emitted from the side of the gong 2 from diffusing around the gong 2 and instead directs it forward, thereby strengthening its directionality and increasing its sound pressure.

Furthermore, as will be explained later, the sound pressure of the alarm bell 1 can be increased by the hood 5 even when it is housed within a housing, so the sound pressure of the bell sound does not decrease as it does with conventional alarm bells. In other words, the alarm bell 1 is particularly suitable for installation inside a housing, and the inclusion of the hood 5 offers significant advantages.

[Examples of food]
Cylindrical portion and opening: Specifically, the hood 5 has a cylindrical portion 5a that surrounds the gong 2. One end 5c of the cylindrical portion 5a has an opening 5b that opens toward the front surface of the gong 2, surrounding the gong 2 (see FIGS. 1 and 3). As a result, the bell sound emitted from the gong 2 is emitted toward the front surface of the gong 2 along the cylindrical portion 5a, enhancing directionality and increasing sound pressure.

Hood Height: The hood 5 preferably has a height that exceeds the overall height of the gong 2 when surrounding it (see FIGS. 1(b) and 7). By positioning the opening 5b of the cylindrical portion 5a at a height that exceeds the overall height of the gong 2, all bell sounds emitted from the sides of the gong 2 can be directed toward the front surface of the gong 2. This effectively increases the sound pressure of the bell sounds emitted from the gong 2. The height of the hood 5 may be the same as the overall height of the gong 2 or may be lower than that height. Furthermore, the height may vary circumferentially.

Furthermore, as will be explained later, when the alarm bell 1 is installed inside a housing, the front panel-side end 5c of the hood 5, where the opening 5b through which the bell sound is emitted is provided, can be in contact with or close to the sound hole provided in the front panel of the housing. This allows the bell sound, with increased sound pressure emitted from the opening 5b of the hood 5, to be efficiently emitted outside the housing from the sound hole.

Shape of the Cylindrical Portion In the illustrated example, the hood 5 has a cylindrical portion 5a that is a rectangular tubular shape (see FIGS. 1 and 3). This cylindrical shape may be a rectangular tubular shape of another polygonal shape or a cylindrical shape. In the illustrated example, the cylindrical portion is tapered toward the opening 5b. This shape is more suitable for increasing the sound pressure of the bell sound. The shape toward the opening 5b may be tapered, or may be a straight tubular shape with no change in thickness. In either case, it is preferable that the size of the opening 5b be approximately the same as the size of the sound hole in the front panel of the housing (in the example shown in FIGS. 6 and 7, which will be described later, the size of the opening 5b is slightly larger than the sound hole 10b).

In the illustrated example, the hood 5 is formed by assembling two identically shaped components 5A, 5A' that are divided into two equal halves in the circumferential direction (see FIG. 4). Specifically, the components 5A, 5A' have, on both circumferential end surfaces, recesses 5e and protrusions 5f, and recesses 5e' and protrusions 5f', respectively, as fitting portions between the components (these fitting portions also have the same shapes (including positions) between the components). The recess 5e of one component 5A fits into the protrusion f' of the other component 5A', and the protrusion 5f of one component 5A fits into the recess 5e' of the other component 5A', thereby forming the cylindrical hood 5.

By making the hood 5 out of multiple parts of the same shape, such as the two parts 5A and 5A', it is possible to mold these multiple parts from a synthetic resin material using only one mold, thereby reducing manufacturing costs. The number of identically shaped parts that make up the hood 5 may be more than two, but two is more advantageous in terms of ease of assembly.

Mounting Portion The hood 5 has mounting portions 5d, 5d' at the end opposite the opening 5b for mounting a metal fitting 6 (an example of a mounting part) described below (see FIGS. 3(b) and 7). In the illustrated example, the mounting portions 5d, 5d' are provided as recesses into which the insertion portion of the mounting fitting 6 is inserted. The mounting portion 5d will be described further below together with the mounting fitting 6.

[Mounting bracket (example of mounting parts)]
The alarm bell 1 further comprises a mounting bracket 6 which is used to mount the gong 2 at a predetermined position within the housing when the alarm bell 1 is to be installed housed within the housing.

The mounting bracket 6 is made of a metal plate member. In the illustrated example, it has a U-shaped cross section and includes a bottom plate 6a that is attached to a predetermined position within the housing using fixing means (screws, etc.) and standoffs 6b, 6b at both longitudinal ends of the bottom plate 6a (see Figure 5). The mounting bracket 6 is attached to a predetermined position within the housing with the standoffs 6b, 6b positioned on the left and right. A receiving portion 6c for attaching the gong 2 is provided in the center of the bottom plate 6a. The gong 2 can be attached by inserting the hook portion 4a of the rear side of the housing 4 into the receiving portion 6c from above, so that it is attached to the bottom plate 6a with the front side facing forward.

The hood 5 is attached to the mounting bracket 6 in a manner that surrounds the gong 2. Specifically, the two parts 5A and 5A' of the hood 5 are assembled to each other from either side of the width of the bottom plate 6a, sandwiching the gong 2 from above and below. The two widthwise ends of the bottom plate 6a are then inserted into the mounting portions 5d and 5d' on both parts, so that the tubular portion 5a is attached to the mounting bracket 6 in a manner that surrounds the gong 2 on the bottom plate 6a (see Figure 7).

The left and right standing pieces 6b, 6b of the mounting bracket 6 are provided to be positioned on the outside of the hood 5 when the hood 5 is attached. The standing pieces 6b, 6b function as guards for the hood 5, which is positioned on the inside.

[Example of storage inside the housing]
As described above, the alarm bell 1 can be installed by being housed inside a housing such as a fire hydrant box, an equipment housing box, etc. Figures 6 and 7 show, as an example, how the alarm bell 1 is housed when it is installed by being housed inside an equipment housing box.

The equipment housing box 10 is used in an automatic fire alarm system, and as shown in the figure, it houses an alarm bell 1 as a local sound device, as well as an indicator light and transmitter (the housing portion is not shown), with parts of them (such as the display section 10c and push button section 10d) exposed to the outside.

Specifically, as shown in Figure 7, the alarm bell 1 is stored inside the equipment housing box 10, with the gong 2 and the hood 5 surrounding it attached to a frame member on the front panel 10a with screws through screw holes in the mounting bracket 6.

At this time, the hood 5 surrounds the gong 2, with the opening 5b opening toward the sound hole 10b located in front of the surface of the gong 2.

Therefore, even when the alarm bell 1 is stored inside the equipment housing box 10, the sound pressure can be increased by the hood 5, and the increased sound pressure bell sound can be emitted outside the equipment housing box 10 through the opening 5b and sound hole 10b.

Furthermore, in the illustrated example, the end of the alarm bell 1 where the opening 5b of the hood 5 is provided is close to the part of the front panel 10a where the sound hole 10b is provided. This allows the bell sound, with increased sound pressure emitted from the opening 5b of the hood 5, to be efficiently emitted from the sound hole 10b to the outside of the equipment housing box 10.

The end of the hood 5 where the opening 5b is provided may be in contact with the portion of the front panel 10a where the sound hole portion 10b is provided.

[Mounting bracket with detachable part (another example of mounting part)]
The alarm bell 1 may also be installed directly on the wall of a building without being housed inside a housing. In this case, it may be installed without the hood 5. The mounting bracket 7 shown in Figure 8 is an example of a mounting part that can be suitably used when the alarm bell 1 is installed without the hood 5.

Like the mounting bracket 6, the mounting bracket 7 is made of a metal plate member and has a bottom plate 7a that is attached to a predetermined position inside the housing by a fixing means, and standing pieces 7b, 7b at both ends of the length of the bottom plate 7a. A receiving portion 7c is provided in the center of the bottom plate 7a into which the hook portion 4a on the back side of the gong 2 is inserted.

The mounting bracket 7 differs from the mounting bracket 6 in that the bottom plate 7a has a detachable portion 7d that can be easily separated by the user. The receiving portion 7c is provided on this detachable portion 7d.

When the detachable portion 7d is not separated, the mounting bracket 7 can be used to attach the hood 5 and to hang the gong 2, just like the mounting bracket 6. If the detachable portion 7d is separated, the hood 5 cannot be attached, but the gong 2 can still be hung if the detachable portion 7d is used as a mounting part.

In other words, when the alarm bell 1 is installed inside a housing, such as when the alarm bell 1 is installed with the hood 5 attached, the mounting bracket 7 can be used as is as a part for attaching to the object without separating the detachable portion 7d. On the other hand, when the alarm bell 1 is installed without being installed inside a housing, such as when the alarm bell 1 is installed without the hood attached, the detachable portion 7d can be separated and the separated part can be used as a part for attaching to the object.

The detachable portion 7 can be formed using various metal processing techniques. In the example shown, the connecting portions 7e, 7e with the bottom plate portion 7a are cut while leaving only a small portion, and the connecting portions 7e are thinned so that they can be easily separated. However, the processing method is not limited to this, as long as they can be easily separated.

[Configuration change example]
In the alarm bell 1, for example, the configuration can be changed as follows.

Instead of being made up of multiple parts of the same shape assembled together, the cylindrical portion 5a of the hood 5 may be made up of multiple parts of different shapes assembled together, or it may be made up of a single part formed as a single unit.

The hood 5 may be attached to the housing 4 instead of to the mounting brackets 6 and 7.

The hood 5 and mounting bracket 6 may be manufactured as a single unit instead of being separate components.

1: Alarm bell 2: Gong 3: Striker 4: Housing 4a: Hook 5: Hood 5A, 5A': Part 5a: Cylindrical part 5b: Opening 5c: End 5d, 5d': Mounting part 5e, 5e': Recess 5f, 5f': Convex part 6: Mounting bracket 6a: Bottom plate 6b: Standing piece 6c: Receiving part 7: Mounting bracket 7a: Bottom plate 7b: Standing piece 7c: Receiving part 7d: Separable part 7e: Connecting part 10: Equipment housing box 10a: Front panel 10b: Sound hole 10c: Display 10d: Push button

Claims (2)

An alarm bell that sounds an alarm by striking a gong, and that includes a cylindrical hood that surrounds the gong,
the gong further includes an attachment part for attaching the gong to an attachment object, and the hood is attached to the attachment object together with the gong by the attachment part;
The mounting part has a bottom plate portion and a detachable portion, the detachable portion being provided on the bottom plate portion and detachably connected thereto, and when the alarm bell is to be installed without the hood being attached, the detachable portion can be detached from the mounting part and used as a part for attaching the gong to an object to be attached. An alarm bell as described in claim 1, characterized in that the mounting part is plate-shaped.