JPH08148916A - In-vehicle antenna device - Google Patents

Abstract

(57) [Summary] [Purpose] A large parallel force is applied in the mounted state,
Even if it is repeatedly attached and removed, there is no risk of damaging the painted surface of the body, the gap between the body surface and the magnet attractor is small, and a strong attracting force is obtained, so that the mounting position can be changed without any problem. An in-vehicle antenna device is provided. [Structure] A magnet attractor 5 in which a dish-shaped yoke 5a having a central convex portion and a flat ring-shaped magnet 5b are combined is disposed on the bottom surface of the case 2 while being exposed to the outside. A thick and elastic protective sheet 8 made of an epoxy-impregnated polyester cloth sheet or a silicone rubber sheet was attached to the joint surface of the vehicle body and the peripheral bottom surface of the case with an adhesive.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-mounted antenna device in a car navigation system utilizing a GPS (Global Positioning System), and more particularly to an antenna of a type that is magnetically attracted and attached to a car body surface by a magnet. Regarding the improvement of the device.

[0002]

2. Description of the Related Art As is well known, a vehicle-mounted antenna device for receiving GPS radio waves is built in a flat waterproof case made of plastic, and an antenna cable is pulled out from a side portion. This antenna device is attached to the outer surface of a steel plate automobile body (such as a trunk lid) by utilizing the magnetic attraction force of a magnet.

As the mounting structure utilizing the magnetic attraction force, there are one in which the magnet attractor is exposed outside the bottom face of the case and one in which the magnet attractor is built inside the bottom face of the case of the antenna device. .

[0004]

However, in the former structure, when a large parallel force is applied to the antenna device while it is attached to the vehicle body by the magnetic attraction device, or when the antenna device is repeatedly attached and detached, the body is painted. There is a problem that the surface is easily scratched or cut. In particular, scratching a high-grade painted surface deteriorates the appearance of the automobile, and repairing it is not easy.

Further, in the latter construction, the plastic case surface contacts the vehicle body, so the contact is relatively soft and there is a surface that is less likely to damage the body than the former case where the metal magnet attractor directly contacts the vehicle body. However, in the magnet built-in type, the gap between the vehicle body and the magnet becomes very large, so that a strong magnet cannot obtain a sufficient attracting force, and thus it is large and expensive. Even with the magnet built-in type, if fine particles of dust are caught between the bottom of the case and the car body, the painted surface of the body will be damaged.

Therefore, in general, for the purpose of protecting the painted surface of the body, an adhesive resin foil sheet made of a resin material such as mylar or polyester is pasted on the surface of the vehicle body where the antenna device is attached, and the resin sheet is placed on top of it. The antenna device is magnetically attracted to. However, since this resin foil sheet is very thin, there is a problem in that the sheet attached to the vehicle body is gradually damaged and deteriorated, and cannot serve as a protective sheet. Especially when repeatedly removing and reattaching the antenna device when washing the car,
The resin foil sheet may be torn due to the stress of installation / removal and the stress of car wash, resulting in severe wear. Also, when changing the antenna mounting position, the resin foil sheet attached to the vehicle body must be peeled off, but once the resin foil sheet with a strong adhesive is attached to the vehicle body surface, it can be peeled off cleanly. It was very troublesome and often scratched the painted surface during the work of peeling off the sheet or removing the adhesive remaining on the vehicle body.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to prevent a damage on a painted surface of a body even if a large parallel force is applied in a mounted state or repeated mounting and dismounting. An object of the present invention is to provide a vehicle-mounted antenna device that has a small gap between the surface of the vehicle body and the magnet attracting device, can obtain a strong attracting force, and can change the mounting position without any problem.

[0008]

In view of the above, according to the present invention, a magnet adsorber, which is a combination of a dish-shaped yoke and a flat ring magnet, is arranged on the bottom surface of the case while being exposed to the outside. A thick and elastic protective sheet made of an epoxy-impregnated polyester cloth sheet or a silicone rubber sheet was attached to the vehicle body joint surface of the adsorber and the peripheral bottom surface of the case with an adhesive.

[0009]

[Function] Since the body joint surface on the bottom of the case is covered with a thick and elastic protective sheet made of epoxy-impregnated polyester cloth sheet or silicone rubber sheet, it is better than the conventional antenna device in which a magnet is housed in a plastic case. The contact with the car body surface is much softer, and there is almost no risk of damaging the painted surface of the body. Even though the protective sheet is thick, it is much thinner than the bottom plate of the plastic case in the case of the conventional built-in magnet type, and therefore the gap between the magnet attractor and the vehicle body surface is kept sufficiently small. . Therefore, a strong magnetic attraction force can be obtained.

[0010]

1 to 3 show the structure of a vehicle-mounted antenna device according to an embodiment of the present invention. As shown in detail in FIG. 1, the antenna body 1 is sealed in a flat case 2 made of plastic, and the antenna cable 3 is pulled out from the side portion of the case. The case 2 is composed of an upper case 2a and a lower case 2b, and a gasket 4 is sandwiched between the combination surfaces of the upper case 2a and the lower case 2b so as to have waterproofness and airtightness, and both are fastened with a plurality of screws 10.

A circular recess 2c is formed on the bottom surface of the lower case 2b, and a magnet attractor 5 is attached to the recessed portion 2c. As shown in detail in FIG. 2, the magnet attractor 5 is a combination of a dish-shaped yoke 5a having a central convex portion and a flat ring-shaped magnet 5b. The ring-shaped magnet 5b is joined to the yoke 5a by a double-sided adhesive sheet 6, and the yoke 5a is joined to the recess 2c on the bottom surface of the case by a double-sided adhesive sheet 7.

The lower surface of the magnet attractor 5 and the lower case 2b
The lower surface (around the recess 2c) is substantially flush, and this is the vehicle body joint surface. A thick and elastic epoxy-impregnated polyester cloth sheet (for example, NO.351 manufactured by Nitto Denko Corporation) or a protective sheet 8 made of a silicone rubber sheet is attached to the joint surface of the vehicle body with an adhesive. As shown in FIG. 3, in order to attach the antenna device to the vehicle body 9, there is no need to attach a resin foil sheet to the body surface as in the conventional case, and the protective sheet 8 on the bottom surface of the antenna device can be directly bonded to the body. Good.

[0013]

In the vehicle-mounted antenna device of the present invention, since the vehicle body joint surface on the bottom surface of the case is covered with the protective sheet made of the thick and elastic epoxy impregnated polyester cloth sheet or silicon rubber sheet, the inside of the plastic case It is much softer to hit the surface of the car body than a conventional type antenna device that houses a magnet, and there is almost no risk of damaging the painted surface of the car body. Therefore, it is not necessary to attach the resin foil sheet to the vehicle body side, and therefore the mounting position of the antenna device can be freely changed.

Although the protective sheet is thick,
Compared with the thickness of the bottom plate of the plastic case in the case of the conventional magnet built-in type, the gap between the magnet adsorber and the vehicle body surface is kept sufficiently small. Therefore, a strong magnetic attraction force can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a vehicle-mounted antenna device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a magnet attractor in the apparatus of the above embodiment.

FIG. 3 is a view showing a state in which the above antenna device is attached to an automobile body.

[Explanation of symbols]

1 antenna body 2 case 2a upper case 2b lower case 2c recess 3 antenna cable 4 gasket 5 magnet adsorber 5a dish-shaped yoke 5b ring magnet 6,7 double-sided adhesive sheet 8 protective sheet made of epoxy impregnated polyester cloth sheet or silicone rubber sheet 9 Car body

Claims (1)

[Claims] 1. An in-vehicle antenna device in which an antenna body 1 is sealed in a flat case 2 made of plastic, and an antenna cable 3 is pulled out from a side portion of the case, which is a dish-shaped yoke 5a and a flat ring magnet. The magnet attracting device 5 in which 5b is combined is a bottom part 2 of the case 2.
The protective sheet is made of an epoxy-impregnated polyester cloth sheet or a silicone rubber sheet, which is disposed so as to be exposed to the outside in c and is thick and elastic on the vehicle body joint surface of the magnet adsorber 5 and the peripheral bottom surface of the case. 8. An in-vehicle antenna device, wherein 8 is attached with an adhesive.