JPH0643878A - Electronic alarm - Google Patents

Abstract

PURPOSE:To secure the air-permeability with a simple structure and to prevent penetration of water and dust by providing the housing of an electric alarm with air holes and sealing up them with a porous body. CONSTITUTION:A housing 4 of the alarm is provided with air holes 11, and a porous body 10 is stuck on these air holes 11 to seal up them. The installation position, the form, and the number of air holes 11 are not especially limited, and the porous bode 10 which seals up air holes 11 can take a form of a porous film, a porous plate, or the like. Thus, the electric alarm which prevents penetration of water and dust to the inside as a cause of a failure in sounding of the alarm and secures the permeability between the inside of the alarm and the outside to prevent corrosion of electric contacts and mechanism parts on the inside is inexpensively produced in a simple production process.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an electric horn,
In particular, the present invention relates to an electric horn used for automobiles, motorcycles, snowmobiles, small ships and the like.

[0002]

2. Description of the Related Art Electric horns are available for alternating current and direct current. The AC horn is of a type that directly excites the vibration system by an AC power source such as a flywheel dynamo, and has a simple structure without an internal contact / interruption mechanism. This AC horn has a high degree of durability and safety, but because the sound pressure and timbre change depending on the speed, and because it affects the clarity of sound compared to that for DC, it is special for light motorcycles and cultivators that do not have a storage battery. It is used as a simple horn for vehicles.

DC horns include flat type, spiral type and trumpet type. As shown in FIG. 5, the flat type has a core-2 that constitutes an electromagnet with respect to the housing 4.
0, the coil 21, the diaphragm (diaphragm) 6, and the interrupter 23 having the contact 22, and the bracket 3 are mounted. In this flat type, the vibration of the diaphragm 6 and the resonator 24 formed integrally with the diaphragm 6 are sounded by the impact of the armature 25 and the core 20, and the whole surface is covered.
It resonates efficiently to radiate. In the spiral type and the trumpet type, acoustic efficiency is improved by providing a trumpet-shaped sound path 12 or 13 and causing resonant radiation.

Compared with the AC horn, the DC horn as described above does not change the sound pressure timbre with the speed, and the timbre is clear. Therefore, it is widely used in automobiles, motorcycles, snowmobiles, and so on. It is used in small vessels.

However, since such a DC-type horn has an electric contact and a movable part inside, it is necessary to protect it from the intrusion of water and dust. In particular, measures are taken against damage to the contacts due to water and moisture and the progress of electrolytic corrosion, and a gasket 5 is provided between the housing 4 of the horn and the front cover 26.
There is a safety sealed type (Fig. 5) sandwiching it, and a type with a vent hole (Fig. 6). Further, the shape of the vent hole also includes a drainage hole type (FIG. 6) and a type with a water intrusion prevention hose 9 (FIG. 7).

[0006]

However, in the case of the completely sealed type shown in FIG. 5, water may be sucked into the horn from the gasket due to the difference between the internal pressure of the horn and the external pressure. Since the water that has entered is difficult to escape, corrosion inside the horn progresses, which may cause noise. Further, in the case of the vent hole type shown in FIGS. 6 and 7, dust, sand, etc. often enter the inside of the horn and cause noise. The one with the water intrusion prevention hose is more difficult for dust and the like to enter than the drainage hole type, but there is a problem that the manufacturing process becomes complicated and the manufacturing cost is increased.

The present invention is intended to solve the above-mentioned conventional problems, and an object of the present invention is to ensure the breathability of a horn and to cause the horn not to sound such as water and dust. Another object of the present invention is to provide an electric phonophone that has a structure that does not intrude into other parts and that can be manufactured at low cost by a simple structure process.

[0008]

SUMMARY OF THE INVENTION The present invention is to solve the above-mentioned problems by providing a ventilation hole in a housing of an electric horn and sealing the ventilation hole with a porous body.

[0009]

The present invention prevents the entry of water and dust into the inside of the electric horn by sealing the ventilation holes provided in the housing with a porous body (for example, a porous film), and It ensures breathability with the outside and allows moisture that has entered the inside to be quickly dissipated.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a first embodiment of the present invention in a flat type horn. In this embodiment, the housing 4 is provided with the vent holes 11, and the porous film 10 is attached in a manner to seal the vent holes 11.

FIG. 2 shows a second embodiment of the present invention in a spiral horn. As in the first embodiment, the porous film 10 is attached so as to seal the ventilation hole 11 of the housing 4. In addition, FIG. 3 shows a third embodiment of the present invention in a trumpet-type horn. As in the first embodiment, the porous film 10 is attached so as to seal the ventilation hole 11 of the housing 4.

Next, FIG. 4 shows an example in which the water intrusion prevention hose 9 and the practice of the present invention are combined. In this case, the porous film 10 can be fixed with a water intrusion hose or the like.

While the preferred embodiment has been described above, this is not meant to limit the scope of the invention. That is, the installation position of the vent holes, the shape of the vent holes, and the number of vent holes in the electric horn are not particularly limited. Further, although the shape of the porous body that seals the vent holes is the porous film in the present embodiment, the shape of the porous body is not limited, and other forms such as a porous plate may be adopted. It is a thing.
From the above description, many modifications that are within the spirit and scope of the present invention will be apparent to the parties.

[0014]

As described above, according to the present invention,
By providing a ventilation hole in the housing of the electric horn and sealing this hole with a porous body, the entry of water, dust, etc. into the horn that may cause the horn to stop is prevented. In addition, there is an effect that it is possible to inexpensively manufacture an electric alarm device that secures air permeability between the inside and outside of the sound alarm device and prevents corrosion of internal electrical contacts and mechanical parts by a simple manufacturing process.

[Brief description of drawings]

FIG. 1 is a plan view (a), a cross-sectional view (b), and a detailed view (c) of a cross section near a vent hole of a flat electric horn with a porous membrane of the present invention.

FIG. 2 is a plan view (a) and a cross-sectional view (b) of the spiral wound type electric horn with a porous film of the present invention.

FIG. 3 is a plan view (a) and a sectional view (b) of a trumpet-type electric horn with a porous film according to the present invention.

FIG. 4 is a cross-sectional view of an example in which the ventilation hole with a porous membrane of the present invention is also used as a water intrusion prevention hose.

FIG. 5 is a plan view of an example of a conventional completely sealed type (a).
It is a sectional view (b).

FIG. 6 is a plan view of a conventional drainage hole type (a).
It is a sectional view (b).

FIG. 7 is a plan view (a) and a sectional view (b) of a conventional type with a water intrusion prevention hose.

[Explanation of symbols]

 1 Terminal 2 Adjusting Screw 3 Bracket 4 Housing 5 Gasket 6 Die Toughram 7 Drain Hole Type Venting Hole 8 Venting Hole 9 Water Ingress Prevention Hose 10 Porous Membrane 11 Venting Hole 12 Swirl Resonance Part 13 Trumpet Resonance Part 20 Core 21 Coil 22 Contact 23 Intermitter 24 Resonator 25 Armature 26 Front cover

Claims (1)

[Claims] 1. An electric horn in which the housing is provided with a vent hole, and the vent hole is sealed with a porous body.