JP3206319B2 - Antenna unit for navigation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a receiving antenna unit of a navigation system.

[0002]

2. Description of the Related Art As is well known, an antenna unit as shown in FIGS. 4 and 5 is known as a receiving antenna unit of a navigation system. That is, this antenna unit is, for example, a roof panel X of an automobile or the like.
Etc., which can be adsorbed on the surface of an object as required, and inside a circular unit case B whose bottom surface is covered with a bottom cover A made of zinc or aluminum die-cast, a unit substrate C for mounting a large number of circuit elements and An antenna body D for receiving radio waves from a geostationary satellite or the like is built in.

That is, a waterproof seal E is interposed between the bottom cover A and the unit case B in order to prevent rainwater or the like from entering the inside of the bottom cover A and the unit case B constituting the outer case. The bottom cover A and the unit case B are assembled with a plurality of assembly screws F screwed from the bottom surface of the bottom cover A.

In order to magnetically detachably attach the antenna unit to the surface of the object, a bottom recess a is formed on the bottom surface of the bottom cover A, and a plurality of fixing screws are formed in the bottom recess a. A back yoke H made of a ferromagnetic material fixed at G is located. That is, a plurality of mounting pieces h are bent and formed on the outer peripheral surface of the back yoke H which can be accommodated in the bottom recess a, and a circular permanent magnet ring I is attracted to the surface of the back yoke H. By the magnetic force of the ring I, the antenna unit can be mounted on the surface of a roof panel X of an automobile or the like.

[0005] The symbol "J" is an antenna code for connection to a navigation device not shown.

[0006]

However, in the conventional antenna unit as described above, the bottom cover A and the unit case B are fixed with a tool such as a screwdriver.
Therefore, the work efficiency is poor, and the use of a plurality of assembly screws F increases the component cost.

Further, the back yoke H of the antenna unit is also fixed to the bottom cover A with a plurality of fixing screws G, so that the work efficiency is similarly poor and the number of parts is increased.
There is a disadvantage that the parts cost is relatively high.

An object of the present invention is to solve the above-described problem of the antenna unit of the conventional navigation device,
An object of the present invention is to provide an antenna unit of a navigation device that can be efficiently assembled without using any tools or assembly screws.

[0009]

In order to achieve this object, a first aspect of the present invention is to provide an antenna for a navigation apparatus which houses a circuit board and an antenna body inside an outer case composed of a bottom cover and a unit case. In the unit, a bottom surface of a housing portion integrally formed on a surface of the bottom cover and capable of housing the circuit board and the antenna body
Has a recess for dropping the permanent magnet and back yoke
The lower surface of the formed unit substrate facing the recess is made of magnetic material.
Covered with a shield case made of
Antenna body by the magnetic force of the
Is fixed to the bottom cover . A second invention for achieving this object is the first invention.
In the antenna unit of the navigation device according to the present invention, the housing portion has a cylindrical shape, and is screwed to the housing portion.
The cylindrical joints that can be combined with the cup-shaped unit case
Integrally molded inside, the cylindrical housing part and the cylindrical joint part
Achieved by a screwed structure. Another object of the present invention is to provide a structure excellent in waterproofness. However, in the antenna unit of the navigation device according to the second invention , the object is to be seated on an end face of the storage portion or the cylindrical joint portion. This is achieved by a configuration in which the internal space of the storage section is waterproofed with a waterproof seal. Another object of the present invention is to provide a structure having an excellent appearance.
In the antenna unit of the navigation device according to the first, second, or third aspect of the invention, the outer diameter of the bottom cover is made smaller than the outer diameter of the unit case.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to FIGS. FIGS. 1 and 2 show an antenna unit according to a first embodiment of the present invention. An outer case of the antenna unit has a bottom cover 1 formed of a substantially disc-shaped resin and a circular shape having the same outer shape as the bottom cover 1. The bottom cover 1 and the unit case 2 include a unit substrate 3 and an antenna main body 4 which are composed of a unit case 2 formed of a resin in a cup shape. That is, on the surface of the bottom cover 1, a cylindrical housing part 1a in which the unit substrate 3 and the antenna main body 4 whose lower surfaces are covered with a shield case 5 made of a ferromagnetic material is housed. A seal receiver 1b surrounding the outer periphery is integrally formed, and a male screw 6 is formed on the outer peripheral surface of the distal end of the cylindrical housing portion 1a.

Also, on the lower surface of the unit case 2,
Although a cylindrical joint portion 2a having an inner diameter slightly smaller than the outer shape of the cylindrical housing portion 1a is integrally formed, a female screw 7 capable of engaging with the male screw 6 is formed on the inner peripheral surface of the distal end of the cylindrical joint portion 2a. Is done. A ring-shaped waterproof seal 8 is seated between the distal end face 2b of the cylindrical joint 2a and the end face 1c of the seal receiver 1b. The seal 8 shields the internal space Y of the cylindrical housing 1a from the outside.

The above-mentioned cylindrical housing portion 1a of the bottom cover 1
The relationship between the cylinder housing 2a and the cylindrical joint 2a of the unit case 2 is not limited to such a relationship.
Is larger than the outer dimension of the cylindrical joint 2a,
A female screw may be formed in the cylindrical housing portion 1a and a screw may be formed in the cylindrical joint portion 2a. Although the antenna code 9 is coupled to the unit substrate 3 for coupling with a navigation device not shown, the antenna code 9 is disposed in a connection hole 1 d formed in a part of the outer periphery of the bottom cover 1. become.

On the other hand, a permanent magnet ring 10 and a circular back yoke 11 for adsorbing the antenna unit to a roof panel or the like of an automobile are provided on the bottom surface of the cylindrical housing portion 1a.
Is formed, but the permanent magnet ring 10 and the back yoke 11 can be formed on the surface of the recess 1e only by fixing the permanent magnet ring 10 with an adhesive without using any fixing means. , The shield case 5, the unit substrate 3, and the antenna body 4 are naturally held by the bottom cover 1.

Since the antenna unit according to the first embodiment has the above structure, it can be assembled without using any tools. That is, when the permanent magnet ring 10 is fixed in the recess 1e of the bottom cover 1 with an adhesive and the back yoke 11 and the unit substrate 3 are positioned on the permanent magnet ring 10, the back yoke 11 and the unit substrate 3 The cylindrical housing 1 is formed by the magnetic force of the permanent magnet ring 10.
a is held in the internal space Y and is fixed. Therefore, after the antenna cord 9 is laid on the connection hole 1d of the bottom cover 1 and the waterproof seal 8 is positioned on the end face of the seal receiver 1b, the cylindrical joint portion 2a of the unit case 2 is applied to the cylindrical housing portion 1a of the bottom cover 1. When the unit case 2 is rotated with respect to the bottom cover 1, an assembled state as shown in FIG. 2 is obtained.

In this assembled state, the waterproof seal 8 is tightened between the seal receiver 1b and the front end face 2b of the unit case 2, so that the liquid-tight state of the internal space Y of the cylindrical housing portion 1a can be maintained. For this reason, according to the structure of the first embodiment, it is possible to eliminate the assembling screws and the fixing screws, reduce the cost of parts, and obtain an effect of assembling efficiently. It goes without saying that the antenna unit of the first embodiment can be attracted to the roof panel (not shown) of the automobile by the magnetic force of the permanent magnet ring 10.

FIG. 3 is a sectional view, corresponding to FIG. 2, of an antenna unit according to a second embodiment of the present invention, in which structural parts similar to those of the first embodiment are denoted by the same reference numerals. Second
Features of the embodiments is that the outside dimension L ₂ of the unit case 2 than the outer dimension L ₁ of the bottom cover 1 and the point which is a large, in that seated a waterproof seal 8A to the cylindrical housing part 1a of the bottom cover 1 .

Since the antenna unit of the second embodiment has such a structure, the bottom cover 1 is assembled in a state of being hidden inside the unit case 2, so that the appearance seen from the lateral direction is improved. And the bottom is the bottom cover 1
Between the cylindrical housing portion 1a of the bottom case 1 and the cylindrical housing portion 1a of the bottom cover 1,
The internal space Y of the cylindrical housing portion 1a is formed only by the waterproof seal 8A.
Can be sealed.

[0018]

As is apparent from the above description, according to the present invention, the antenna unit structure which can be assembled without using any tools by eliminating the assembling screws and the fixing screws is inexpensive in manufacturing cost. Not only can be obtained, but also an efficient assembly process in which the unit case is screwed into the bottom cover.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a partially cut-away antenna unit of a navigation device according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional view of the antenna unit.

FIG. 3 is a sectional view corresponding to FIG. 2 of an antenna unit according to a second embodiment of the present invention;

FIG. 4 is an exploded perspective view showing a partially cut-away antenna unit of a conventional navigation device.

FIG. 5 is a vertical sectional view of the antenna unit.

[Explanation of symbols]

 Y Internal space 1 Bottom cover 1a Cylindrical housing 1e Recess 2 Unit case 2a Cylindrical joint 3 Unit board 4 Antenna body 5 Shield case 6 Male thread 7 Female thread 8, 8A Waterproof seal

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04B 1/08 G01C 21/00 H01Q 1/22

Claims (3)

(57) [Claims] 1. An antenna unit of a navigation device for accommodating a circuit board and an antenna body inside an outer case formed by a bottom cover and a unit case , wherein the circuit board and the antenna are integrally formed on a surface of the bottom cover. On the bottom of the storage section that can store the main body ,
A recess is formed to drop the permanent magnet and back yoke.
The lower surface of the unit substrate facing the recess is made of magnetic material.
Covered with a shield case, said shield case and front
Due to the magnetic force with the back yoke, the antenna body
Navigation fixed to the system cover
The antenna unit of the device. 2. The container according to claim 1, wherein said housing portion has a cylindrical shape.
The cylindrical joint that can be screwed to the
The cylindrical housing and the circle
2. The cylindrical joint according to claim 1, wherein the cylindrical joint is screwed.
Antenna unit of the on-board navigation device. 3. An antenna unit for a navigation device according to claim 2 , wherein an inner space of said storage portion is waterproofed by a waterproof seal seated on an end face of said storage portion or said cylindrical joint portion.