JP2002217622A - Antenna element-mounting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an antenna element from being removed from an antenna substrate. SOLUTION: A tapered projection section 13b whose diameter has been expanded is provided at the tip of an engagement drawing section 13a being drawn from the lower end of an element-mounting screw section 13 that is provided at the lower end of an element base part 13 of the antenna element. When a screw section 13e of the element base section 12 is screwed to a hot fixture 20, the tapered projection section 13b passes through a push nut 22, and engages with the push nut 22, thus preventing the antenna element from being removed from the antenna cover 3a of the antenna substrate carelessly. The push nut 22 is stuck into an antenna-mounting section 10 freely by the hot fixture 20 and a fixing metal 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna element mounting structure for mounting an antenna element, and is particularly suitable for application to a vehicle-mounted antenna.

[0002]

2. Description of the Related Art There are various types of antennas mounted on a vehicle body. If an antenna is mounted on a roof located at the highest position in a vehicle body, reception sensitivity can be increased. For this reason, an in-vehicle antenna attached to a roof of a vehicle body has been used conventionally. Also,
Since an FM radio and an AM radio are generally provided in the vehicle body, an antenna that can receive both the FM radio band and the AM radio band is convenient.
Generally, two radio bands can be shared and received.

Such an in-vehicle antenna is shown in FIG.
The antenna element 100 as shown in FIG.
1 and is screwed and fixed to the antenna base 103. The antenna element 10 shown in FIG.
0 denotes a flexible element base 112 that can be bent when receiving a load from the side, a whip element 111 extending from the element base 112, and an antenna top provided at the tip of the whip element 111. 11
1a. A coil can be built in the element base 112, and the antenna element 100 can operate at multiple frequencies by the action of the coil. Whip element 11
The helical projection 1 is formed with a helical projection in order to prevent wind noise that is likely to occur during high-speed running. The antenna element 100 is provided at the lower end of the element base 112.
Is formed so that an element mounting screw portion 113 for screwing the element to the antenna base 103 projects. The element mounting screw portion 113 is
Also serves as a power supply.

FIG. 10B shows a detailed configuration of the element mounting screw portion 113. As shown, the element mounting screw portion 113 includes a main body portion 113d, an upper protruding portion 113c, and a screw portion 113e. Upper protrusion 11
Reference numeral 3c denotes a protrusion having a substantially circular cross section to which a coil built in the element base 112 is fitted.
d has a tapered shape as a whole, and has a hexagonal lower end. Also, the screw portion 113e is
03 is a screw portion that is screwed to the antenna mounting portion 110. The element mounting screw portion 113 is integrally insert-molded when the element base portion 112 is formed, and is prevented from rotating with respect to the element base portion 112 by a hexagonal portion of the main body portion 113d.

[0005] The antenna base 103 shown in FIG.
A resin antenna cover 103a having a lower opening;
And a metal antenna base 105 fixed so as to cover the opening surface of the antenna cover 103a. A circuit board 109 is housed in the antenna base 103, and the circuit board 109 incorporates a demultiplexing circuit and an amplifying circuit for amplifying the demultiplexed received signal. The circuit board 109 is fixed to a grounding metal (not shown) by soldering or the like, and the grounding metal is fixed to the upper surface of the antenna base 105. A signal cable 106 for deriving a received signal from the antenna base 103;
A power cable 107 for supplying power to the circuit board 109 is drawn out. Also, on the lower surface of the antenna base 105,
By being inserted into a through hole formed in the roof and screwing a mounting nut from inside the vehicle, a mounting portion for mounting the antenna base 103 to the roof is integrally formed so as to protrude. Further, a flexible rubber or resin pad 104 is fitted to a lower portion of the antenna base 103 so that the antenna base 103 can be attached to the roof in a watertight manner and without being damaged. Further, an O-ring 108 is attached to the root of the mounting portion protruding from the lower surface of the antenna base 105, thereby preventing water from entering the vehicle body.

A metal antenna mounting portion 110 is insert-molded on the antenna base 103, and an element mounting screw portion 113 of the antenna element 100 is detachably screwed to the antenna mounting portion 110. FIG. 12 is a half sectional view showing a detailed configuration of the antenna mounting portion 110. As shown in this figure, the antenna mounting portion 110 is constituted by a hot metal fitting 120 having a hole formed in the center. A screw portion 120b is cut on the inner peripheral surface of the hole formed in the hot metal fitting 120 so that the element mounting screw portion 113 of the antenna element 100 can be screwed. A knurled portion 121c is formed on the outer peripheral surface of the antenna cover 103 when the antenna cover 103 is formed by insert molding.
a.

[0007]

However, in the conventional vehicle-mounted antenna, the antenna element 100
Is fixed to the antenna mounting portion 110 of the antenna base 103 by screwing. That is, the antenna element 100 is detachably fixed to the antenna base 103. For this reason, when the screwing of the antenna element 100 is loosened, the antenna element 100 falls off,
There is a problem that the antenna element 100 is detached from the antenna base 103 and stolen.

Accordingly, an object of the present invention is to provide an antenna element mounting structure that prevents an antenna element from being inadvertently removed from an antenna base when the antenna element is mounted on the antenna base.

[0009]

To achieve the above object, an antenna element mounting structure according to the present invention comprises: an antenna element having an element mounting screw portion at a lower end; and an antenna mounting portion to which the element mounting screw portion is screwed. An engagement base 13a having a tapered projection formed at the tip from the lower end of the element mounting screw portion. When screwed into the antenna mounting portion, the engagement extending portion is inserted into a push nut built in the antenna mounting portion, so that the tapered projection engages with the push nut. I have.

[0010] In the antenna element mounting structure of the present invention, the antenna mounting portion may include a hot metal provided with a screw portion into which the element mounting screw portion is screwed in a through hole, and a hot metal of the hot metal. The push nut, which is made of a fixed metal fitted to a lower portion and is arranged in a step formed in the through hole of the hot metal fitting, is a tip of a ring-shaped protrusion formed in the fixed metal. It may be arranged in a space formed by a surface and the step. Further, in the antenna element mounting structure of the present invention, the diameter of the through hole formed in the push nut is larger than the diameter of the engagement extending portion,
The diameter may be smaller than the diameter of the tapered protrusion.

According to the present invention, when the element mounting screw portion of the antenna element is mounted on the antenna mounting portion of the antenna base, the tapered projection formed on the element mounting screw portion is built into the antenna mounting portion. And the tapered projection is engaged with the push nut. As a result, even if the antenna element is rotated in the reverse direction to remove the antenna element from the antenna base, the antenna element cannot be accidentally removed from the antenna base.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle-mounted antenna to which the antenna element mounting structure of the present invention is applied will be described.
An embodiment of the antenna element mounting structure of the present invention will be described. FIG. 1 shows a configuration of a vehicle-mounted antenna to which the antenna element mounting structure of the present invention is applied. The in-vehicle antenna shown in FIG. 1 is an antenna attached to a roof of a vehicle. This vehicle-mounted antenna includes an antenna element 1 and an antenna base 3 to which the antenna element 1 is attached. The antenna element 1 is provided at a flexible element base 12 that can be bent when receiving a load from a lateral direction, a whip element 11 extending from the element base 12, and a tip of the whip element 11. And an antenna top 11a.

An extension coil is built into the element base 12, and the antenna element 1 can operate at multiple frequencies by the action of the extension coil. The whip element 11 is formed with a helical projection in order to prevent wind noise that is likely to occur during high-speed running. Although not shown, an element mounting screw portion for screwing the antenna element 1 to the antenna base 3 is formed at a lower end of the element base portion 12 so as to project therefrom. The element mounting screw portion also serves as power supply for the antenna element 1.

The antenna base 3 includes a resin antenna cover and a metal antenna base 5 fixed to a lower portion thereof.
And the circuit board can be housed inside. The circuit board incorporates a demultiplexing circuit and an amplification circuit for amplifying the demultiplexed received signal. On the lower surface of the antenna base 5, a mounting nut for mounting the antenna base 3 on the roof is integrally formed by being inserted into a through hole formed in the roof and screwing a mounting nut from inside the vehicle so as to protrude. Have been. Further, a cable (not shown) for extracting a received signal or supplying power to the circuit board is drawn out from the circuit board. Further, a flexible rubber or resin pad 4 is fitted to a lower portion of the antenna base 3 so that the antenna base 3 can be attached to the roof in a watertight manner and without being damaged.

Next, the configuration of the antenna base 3 is shown in FIGS. However, FIG. 2 is a plan view of the antenna base 3, FIG. 3 (a) is a top view thereof, FIG. 3 (b) is a bottom view thereof, and FIG. FIG. As shown in these figures, the antenna base 3 is made of a resin antenna cover 3a having a lower opening.
And a metal antenna base 5 fixed so as to cover the opening surface of the antenna cover 3a. A circuit board 9 is housed in the antenna base 3, and the circuit board 9 incorporates a demultiplexing circuit and an amplifying circuit for amplifying the demultiplexed received signal. The circuit board 9 is fixed to a grounding metal (not shown) by soldering or the like, and the grounding metal is fixed to the upper surface of the antenna base 5. A signal cable 6 for deriving a received signal and a power cable 7 for supplying power to the circuit board 9 are provided from the circuit board 9.
Is a mounting portion 5 formed on the lower surface of the antenna base 5.
a through the through hole. Further, a flexible rubber or resin pad 4 is fitted to a lower portion of the antenna base 3 so that the antenna base 3 can be attached to the roof in a watertight manner and without being damaged. Further, an O-ring 8 is attached to the root of the mounting portion projecting from the lower surface of the antenna base 5, thereby preventing water from entering the vehicle body.

A metal antenna mounting portion 10 is insert-molded on the upper part of the antenna cover 3a constituting the antenna base 3. The antenna element 1 is screwed and attached to the antenna attachment portion 10. The antenna element mounting structure of the present invention is characterized by an antenna mounting portion 10 and an element mounting screw portion 13 (see FIG. 6) provided at a lower end of the antenna element 1. Therefore, a detailed configuration of the antenna mounting portion 10 is shown in a half sectional view in FIG. As shown in FIG. 1, the antenna mounting portion 10 includes a hot metal fitting 20, a fixed metal 21 fitted to a lower end of the hot metal fitting 20, and a push nut 22 which is freely held between the hot metal fitting 20 and the fixed metal 21. It is composed of The hot metal fitting 20 is formed in a substantially cylindrical shape, and has a knurl 21 on its outer peripheral surface.
When c is formed and insert-molded, it is brought into close contact with the antenna cover 3a. A screw portion 20b is cut on the inner peripheral surface of the through-hole so that the antenna element 1 can be screwed thereto.

A stepped portion is formed on the inner peripheral surface of the through hole of the hot metal fitting 20, and a lower portion of the ring-shaped portion 2 having a larger inner diameter is formed.
0a. A ring-shaped protrusion 21a formed so as to protrude from one surface of the fixed metal 21 is fitted to the ring-shaped portion 20a. At this time, the tip of the ring-shaped portion 20a of the hot metal fitting 20 is fixed to the flange 21b of the fixed metal 21.
And the position is regulated. Although this fitting is performed by press fitting, a screw may be provided on both sides and screwed. Then, when the fixed metal 21 is fitted from the lower end of the hot metal 20, the push nut 22 is arranged on the step in the through hole of the hot metal 20, and then the fixed metal 21 is fitted. A push nut 22 can be built into the unit 10. Since the push nut 22 is housed in the space formed by the step portion of the hot metal fitting 20 and the ring-shaped protrusion 21a of the fixed metal 21, the push nut 22 is fixed to the antenna mounting portion 10 in a free state. . Thereby, the antenna mounting portion 10
And the center deviation of the push nut 22 can be absorbed.

FIG. 9 shows a detailed configuration of the push nut 22. As shown in FIG. 9 (a) is a plan view of the push nut 22, and FIG. 9 (b) is a side view thereof. As shown in these figures, a metal push nut 22 having elasticity is used.
Is composed of a disk-shaped main body 22a having a through hole 22d. Through hole 22d of disc-shaped main body 22a
A plurality of cuts 22c are provided in the normal direction from the center. As shown in FIG. 9, the notch 22c allows the through hole 22d to be formed.
Is separated into six pieces, and these pieces are bent downward by several tens of degrees to form a plurality of bent portions 22b inclined so as to reach the through holes 22d.

Next, the detailed configuration of the antenna element 1 is shown in FIG. However, FIG. 6A is a plan view of the antenna element 1, and FIG. 6B is a bottom view thereof. As shown in these figures, the antenna element 1 has a flexible element base 12 that can be bent when subjected to a lateral load, a whip element 11 extending from the element base 12, and a whip. And an antenna top 11a provided at the tip of the element 11. An extension coil can be built in the element base 12, and an element mounting screw portion 13 is fitted to a lower end of the extension coil. At the lower end of the element mounting screw portion 13, an engagement extending portion 13a described later is provided.
In addition, the antenna element 1
Are designed to operate at multiple frequencies. The extension coil and the element mounting screw portion 13 are insert-molded on the element base 12. Further, the whip element 11 is formed with a helical projection as shown in the figure to prevent wind noise that is likely to occur during high-speed running.

The element mounting screw 13 is a feature of the antenna element mounting structure of the present invention, and its detailed configuration is shown in FIG. However, FIG. 7A is a front view of the element mounting screw portion 13, and FIG. 7B is a bottom view thereof. As shown in these figures, the element mounting screw portion 13 includes a main body portion 13d, an upper projecting portion 13c, a screw portion 13e, an engagement extension portion 13a extending from a lower end of the screw portion 13e, and an engagement extension portion 13a. And a tapered projection 13b having an enlarged diameter formed at the tip of the projection. Upper projecting portion 1 formed at the upper end of main body 13d
Reference numeral 3c denotes a projecting portion having a substantially circular cross section to which an extension coil built in the element base 12 is fitted.
d has a tapered shape as a whole, and has a hexagonal lower end. The screw portion 13e formed at the lower end of the main body portion 13d is a screw portion screwed to the screw portion 20b of the hot metal fitting 20 in the antenna mounting portion 10. The element mounting screw portion 13 is formed integrally when the element base portion 12 is formed, and the main body portion 13d
Are prevented from rotating with respect to the element base 12.

When the antenna element 1 is mounted on the antenna base 3, the element mounting screw portion 13 of the antenna element 1 is connected to the antenna mounting portion 10 of the antenna base 3.
Screw. At this time, the tapered protrusion 13b formed at the lower end of the element mounting screw portion 13 contacts the bent portion 22b of the push nut 22 and
b is expanded and inserted into the push nut 22. FIG. 8 is a sectional view showing a state in which the antenna element 1 is attached to the antenna base 3 in this manner. As shown in the figure, the engagement extending portion 13a formed by extending from the screw portion 13e has a through hole 22 of the push nut 22.
d. The inner diameter of the through hole 22d is larger than the diameter of the engagement extending portion 13a, and the tapered projection 1
It is formed smaller than the diameter of 3b.

Then, even if the screw is released by reversely rotating the element mounting screw portion 13 with respect to the antenna mounting portion 10, the boundary between the tapered projection 13b having the increased diameter and the engagement extending portion 13a. Hole 2 of push nut 22 on the surface
The tips of the plurality of bent portions 22b facing 2d come into engagement. As a result, even if the antenna element 1 is to be detached from the antenna base 3, it cannot be inadvertently removed. If the antenna element 1 is strongly pulled out in the engaged state, the tip of the bent portion 22b is pushed upward by the engagement surface, and the diameter of the through hole 22d of the push nut 22 becomes narrower. For this reason, removal can be reliably prevented.

In the antenna element mounting structure of the present invention, the antenna element 1 provided with the element mounting screw portion 13 having the engagement extending portion 13a and the tapered protrusion 13b is mounted on the antenna base 3. However, as shown in FIG.
The antenna element 100 provided with the element mounting screw portion 113 on which the 3a and the tapered protrusion 13b are not formed can be mounted on the antenna base 3. By doing so, the antenna element 100 can be made detachable from the antenna base 3. By the way, in the antenna element mounting structure according to the present invention, the antenna element 1 can be a dual-frequency antenna for AM and FM bands, or a triple-frequency antenna including a telephone band.

[0024]

As described above, according to the present invention, when the element mounting screw portion of the antenna element is mounted on the antenna mounting portion of the antenna base, the tapered projection formed on the element mounting screw portion becomes the antenna mounting portion. The tapered projection is inserted into the push nut incorporated in the push nut so as to engage with the push nut. As a result, even if the antenna element is rotated in the reverse direction to remove the antenna element from the antenna base, the antenna element cannot be accidentally removed from the antenna base.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a vehicle-mounted antenna to which an antenna element mounting structure of the present invention is applied.

FIG. 2 is a plan view showing a configuration of an antenna base in the vehicle-mounted antenna according to the present invention.

FIGS. 3A and 3B are a top view and a bottom view showing a configuration of an antenna base in the vehicle-mounted antenna according to the present invention. FIGS.

FIG. 4 is a cross-sectional view showing a configuration of an antenna base in the vehicle-mounted antenna according to the present invention.

FIG. 5 is a half sectional view showing a configuration of an antenna mounting portion of an antenna base in the vehicle-mounted antenna according to the present invention.

FIG. 6 is a plan view and a bottom view showing the configuration of an antenna element in the vehicle-mounted antenna according to the present invention.

7A and 7B are a plan view and a bottom view showing a configuration of an element mounting screw portion of the antenna element in the vehicle-mounted antenna according to the present invention.

FIG. 8 is a cross-sectional view showing a state in which an antenna element in a vehicle-mounted antenna according to the present invention is attached to an antenna base.

FIG. 9 is a plan view and a side view showing a configuration of a push nut of an antenna base in the vehicle-mounted antenna according to the present invention.

FIG. 10 is a diagram showing a configuration of an antenna element and an element mounting screw portion in a conventional vehicle-mounted antenna.

FIG. 11 is a cross-sectional view showing a configuration of an antenna base in a conventional vehicle-mounted antenna.

FIG. 12 is a half sectional view showing a configuration of an antenna mounting portion of an antenna base in a conventional vehicle-mounted antenna.

[Explanation of symbols]

Reference Signs List 1 antenna element, 3 antenna base, 3a antenna cover, 4 pads, 5 antenna base, 5a
Mounting part, 6 signal cable, 7 power cable, 8
O-ring, 9 circuit board, 10 antenna mounting part, 11
Whip element, 11a Antenna top, 12
Element base, 13 Element mounting screw, 13
a engagement extension, 13b tapered projection, 13c upper projection, 13d body, 13e screw, 20 hot metal fitting, 20a ring-shaped part, 20b screw, 21
Fixed metal, 21a ring-shaped protrusion, 21b flange, 21c knurl, 22 push nut, 2
2a disk-shaped main body part, 22b bent part, 22c cut part,
22d through hole, 100 antenna element, 103
Antenna base, 103a Antenna cover, 104
Pad, 105 antenna base, 106 signal cable, 107 power cable, 108 O-ring, 109
Circuit board, 110 Antenna mounting part, 111 Whip element, 111a Antenna top, 112 Element base, 113 Element mounting screw part, 113
c Upper projecting part, 113d body part, 113e screw part, 120 hot metal fitting, 120b screw part, 120c
Knurl part

Claims (3)

[Claims] An antenna element having an element mounting screw portion at a lower end thereof; and an antenna base having an antenna mounting portion to which the element mounting screw portion is screwed. An engagement extending portion 13a having a tapered projection is provided so as to extend, and when the element mounting screw portion is screwed to the antenna mounting portion, a push built in the antenna mounting portion is provided. The antenna element mounting structure according to claim 1, wherein the engagement extending portion is inserted into the nut, and the tapered projection is engaged with the push nut. 2. The antenna mounting portion includes: a hot metal fitting provided with a screw portion to which the element mounting screw portion is screwed in a through hole; and a fixed metal fitted to a lower portion of the hot metal fitting. Wherein the push nut disposed on a step formed in the through-hole in the hot metal fitting is formed by a tip end surface of a ring-shaped protrusion formed on the fixed metal and the step. The antenna element mounting structure according to claim 1, wherein the antenna element mounting structure is arranged in a space. 3. The diameter of a through hole formed in the push nut is larger than the diameter of the engaging extension and smaller than the diameter of the tapered protrusion. Antenna element mounting structure.