JPS6138249Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an antenna device for a vehicle, and more particularly to an antenna device for an axle in which an antenna element can be easily taken in and out and can be held securely when pulled out.

BACKGROUND ART Conventionally, as vehicle antennas, antenna elements having a multi-stage telescoping type such as a two-stage type, or antenna elements consisting of a single semi-rigid small diameter antenna element are generally known. In recent years, a method has been adopted in which the mounting base is fixed to the roof surface of the vehicle body or the outer surface of the pillar, and the main body part other than the base is housed within the pillar part, in order to prevent wind noise. In particular, in the case of a single small-diameter element having a length of about 1 m, it is convenient to store the element in a dead base such as within a pillar part because the element can be stored in a dead space depending on the shape of the dead space.

However, when using the antenna by pulling it out to the outside of the vehicle, the element itself has an extremely small diameter of approximately 2 to 4 mm, so the retention force of the antenna element retaining spring, which also serves as a power feeder, is not enough to support the vehicle. When the antenna sways on rough roads, the extended antenna element gradually falls down due to its own weight. In addition, if the antenna is used for a long period of time, the spring force holding the antenna will decrease, and the antenna element will fall off while driving, making it impossible to obtain the required antenna length, reducing reception sensitivity, and causing noise when the antenna element slides down. There is a risk of causing problems.

Possible ways to solve these problems include increasing the holding area of the spring or increasing the spring force.

However, since the antenna is installed in a dead space, there is a limit to the length of the spring, and the antenna is often housed in a flexible tube that is curved inside a pillar or other dead space. Therefore, when pulling out the antenna element, the sliding resistance between the antenna, the stopper, and the flexible tube is superimposed, so if the spring force is increased, it becomes difficult to pull out the antenna.
Furthermore, in order to provide appropriate sliding resistance, it has been proposed to provide an extension at the lower end of the antenna element that slides against the inner wall of the flexible tube, but this configuration requires that the flexible tube be made longer. This also raises the problem of where to install the flexible tube.

The present invention was developed in view of the current situation, and its purpose is to provide a vehicle antenna device in which the antenna element can be easily inserted and removed, and the antenna element can be reliably held when pulled out. be.

The present invention focused on the fact that the conventional difficulty was that the feeding spring was also used to hold the antenna element, and the present invention focused on the fact that the feeding spring was also used to hold the antenna element. An elastic member is provided to press and support the stopper.

Embodiments of the present invention will be described below with reference to the drawings.

In Fig. 1, 1 is the body of the axle, and a mounting base 2 made of an insulating material such as synthetic resin is inserted from the outside into a hole in the body 1, and is fixed to the body 1 via a mounting screw 3. has been done.

As shown in the figure, the mounting base 2 is formed into a cylindrical shape with a small diameter hole 2a provided in the center in the vertical direction, and an antenna element 4 having, for example, a spherical stopper 5 at the lower end thereof is inserted into the inside thereof. When the antenna element 4 is pulled out, the stopper 5 is caught in front of the narrow hole 2a, and prevents the antenna element 4 from being pulled out any further.

The antenna element 4 is formed of a single solid semi-rigid rod with a diameter of about 2 to 4 mm, and the stopper 5 at the lower end is formed by bulging the lower end of the antenna element 4 into an appropriate shape, or by molding the lower end of the antenna element 4 into a suitable shape. 4
It is formed by fixing a separate object of an appropriate shape made of synthetic resin or the like to the lower end of the holder. A decorative bead 6 is attached to the upper end of the antenna element 4, as shown in FIG.

A metal tube 7 with a male thread cut at the upper end is press-fitted into the upper hole 2b located above the narrow diameter portion 2a in the mounting base 2, and inside this metal tube 7,
A power supply spring 8 and a sleeve 9 that supports the power supply spring 8 from above are inserted in sequence. The energizing spring 8 and the sleeve 9 are prevented from being pulled out from the metal tube 7 by a cap nut 10 screwed into the male thread at the upper end of the metal tube 7. The power supply spring 8 is
The center portion in the vertical direction is curved toward the antenna element 4 so as to be in constant contact with the antenna element 4, and the contact force is weak enough to maintain the electrical connection with the antenna element 6. There is. This power feeding spring 8 has a power feeding section 11.
A power supply cable 12 is connected through the body 1, and the ground is connected to the body 1 (not shown).

On the other hand, the lower hole 2c located below the small diameter hole 2a in the mounting base 2 has an inner diameter slightly larger than the outer diameter of the stopper 5, and has a lower hole 2c at its lower end. A tapered portion 2d is provided to facilitate insertion of the stopper 5 into the stopper 5. The mounting base 2 at the lower hole portion 2c is provided with two through holes 13 that face each other in the radial direction and have a tapered portion that communicates with the lower hole portion 2c. A ball-like protrusion 14 protrudes into the lower hole 2c, and a spring 15 that biases the protrusion 14 toward the lower hole 2c is provided, and the spring 15 is prevented from coming off by a lid 16. There is. Then, as shown by the imaginary line to the upper end of the lower hole portion 2c, the stopper 5 is pulled up to the upper limit.
Its lower surface side is supported by the protrusion 14, and is securely held within the lower hole 2c. Note that the protrusion 14 may be a protrusion with a sharp tip, or may have a flange provided at the base to restrict the limit of its protrusion.

A flexible insulating tube 18 is connected to the lower end of the mounting base 2 configured in this manner via a ring spring 17.
is normally curved and arranged in a dead space (not shown) or the like. And this insulation tube 1
The antenna element 4 in a retracted state is housed within the antenna element 8 .

Next, the effect will be explained.

When pulling out the antenna element 4, the decorative beads 6 and the like exposed outside the body 1 are grasped and pulled. Then, the antenna element 4 mainly housed within the insulating tube 18 is gradually pulled out. On this occasion,
Since the pressing force of the feeding spring 8 on the antenna element 4 is negligibly small, the resistance required to pull out the antenna element 4 is approximately equal to the sliding resistance between the insulating tube 18, the antenna element 4, and the stopper 5. Therefore, the drawer can be pulled out very easily.

When the antenna element 4 is pulled out further, the stopper 5
is drawn into the lower hole 2c using the tapered portion 2d of the mounting base 2 as a guide, and stops at the position where it abuts against the narrow diameter portion 2a. This corresponds to the maximum extended position of the antenna element 4. At this time, since the lower end of the stopper 5 is supported by the protrusion 14, the stopper 5 is stably held in this position and will not slide down due to vibrations of the vehicle body or the like.

When retracting the antenna element 4, the portion of the antenna element 6 that protrudes to the outside is grasped and pressed downward. Then, the stopper 5 pushes out the protrusion 14 against the biasing force of the spring 15 and passes through this portion. After this, the antenna element 4 is easily housed in the insulating tube 18 with little force.

According to the configuration described above, unlike conventional configurations, the pressing force of the feeding spring on the antenna element is extremely small, so less force is required to move the antenna element in and out. Since it is held securely, it will not fall off while driving. For this reason, there is no risk of problems with antenna power feeding, such as a decrease in reception sensitivity or noise introduced during reception. On the other hand, the feeding spring does not have any role in holding the antenna, unlike conventional ones.
A stable power supply state is maintained permanently with little fatigue. Even if the power supply spring should become defective, it can be replaced from outside the body by removing the cap nut, making the replacement work extremely easy.

2 and 3 show another embodiment of the present invention, in which the protrusion 14 and the spring 1 of the embodiment described above are shown.
Instead of the method of holding the stopper 5 using a spring member 19 provided in the lower hole 2c, the stopper 5 is held using a spring member 19 disposed within the lower hole 2c.

That is, as shown in FIG. 3, the spring member 19 is formed into a cylindrical shape with a flange portion 19a at the upper end and an enlarged tapered portion 19b at the lower end. A slot 20 extending all the way is provided. The spring member 19 is also provided with a curved portion 21 protruding toward the axis at the center in the vertical direction, and a slit 22 for ensuring the elasticity of the curved portion 21. This spring member 19 has a flange portion 19 as shown in FIG.
a is located at the lower end of the upper hole portion 2b, and the tapered portion 1
9b is located in the tapered part 2d, the lower hole part 2
It is arranged and fixed in c. The stopper 5, which has been pulled up to the uppermost end, is supported on its lower side by the curved portion 21 of the spring member 19, as shown in FIG. 2, and is securely held within the lower hole 2c.

The present embodiment described above can also be expected to have the same effects as the embodiments described above.

In addition, although the case where the spring member 19 and the power supply spring 8 are in contact with each other has been described above, they do not necessarily need to be in contact with each other and may be separated from each other.
Furthermore, although the antenna element 4 in both of the above embodiments is constituted by a single rod, it may be of a multi-stage extendable type. Further, the shape of the stopper 5 is not limited to a spherical shape, but may be cylindrical, spindle-shaped, bale-shaped, or the like.

The present invention has been described above based on a preferred embodiment. According to the present invention, the antenna element can be easily put in and taken out, and the antenna element can be held securely and firmly when pulled out. problem is solved.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is a sectional view showing another embodiment of the present invention, and FIG. 3 is a perspective view of the spring member. 2...Mounting base, 4...Antenna element, 5...
Stopper, 8...Power supply spring, 13...Through hole,
14...Tsuko (ball), 15...Spring,
16... Lid body, 18... Insulating tube, 19...
Spring member, 19a...flange part, 19b...tapered part, 20...slit, 21...curved part, 2
2...Slit.

Claims (1)

[Claims for Utility Model Registration] 1. A semi-rigid antenna element having an enlarged stopper at its lower end to prevent extraction, a mounting base into which this antenna element is inserted and which has a power feeding spring in sliding contact with the antenna element, and In a vehicle antenna device comprising an insulating tube that is continuously connected to the lower part of the mounting base and houses the antenna element, the antenna element is pulled into the mounting base at a position below the power supply spring and pulled out to the maximum pull-out position within the mounting base. 1. An antenna device for a vehicle, characterized in that an elastic holding means is provided that bulges into a stopper passage so as to elastically come into contact with the back of a stopper to press and support the stopper and prevent the stopper from retreating. 2. The vehicle antenna device according to claim 1, wherein the holding means comprises a protrusion pressed into the mounting base by a spring. 3. The vehicle antenna device according to claim 1, wherein the holding means is a cylindrical spring member having an inwardly curved portion.