JPH0713292Y2 - Automotive whip antenna mounting base - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a mounting base for an on-vehicle whip antenna mounted on a vehicle such as an automobile.

[Prior Art] Although antennas of various structures are used as antennas for automobile radio, a single-length antenna is pursued as a low-cost antenna provided that it can exhibit the receiving function, which is the minimum requirement among them. There is a whip antenna. This single-length whip antenna is composed of a single continuous rod-shaped conductive member that is tuned to approximately 1/4 wavelength of the FM wave band, and remains exposed to the outside of the vehicle after it is mounted on the vehicle. Therefore, as a material for forming the antenna, a high tensile strength material (for example, high tensile strength stainless steel) having high resilience so that it can sufficiently withstand a load due to an obstacle while the vehicle is running or a load applied during car washing. used.

If this antenna is fixed to the vehicle body at the same time when the vehicle is assembled, a large dead space is created in the space of the transportation vehicle during the subsequent transportation of the vehicle. For this reason, the whip antenna is usually constructed such that it can be attached to and detached from a mounting base that is previously fixed to the vehicle body wall by means of screwing or the like.

Since the whip material forming the antenna is a high tensile strength material, it is poor in workability and is difficult to be threaded. Therefore, it is difficult to screw-connect the mounting base as it is. Therefore, as shown in FIG. 12, the joint 2 is fitted to the base end of the whip antenna element 1,
A structure in which the male screw 3 provided on the joint 2 is screwed into the female screw 6 provided on the connecting member 5 of the mounting base 4 has been adopted. As the material of the joint 2, a material having a lower tensile strength than that of the whip antenna element 1 is used in order to ensure workability, but at the same time, a material that is sufficiently examined in terms of strength is required. Therefore, there is a limit to the purpose of low price.

An even bigger problem is that even if a material that has been thoroughly examined for strength is used, the dimensions of the male screw 3 cannot be increased so much due to screw coupling in a limited space, and as a result, the whip antenna element 1 When the load received when the is bent as shown by the arrow is concentrated on the threaded portion, the male screw 3
The point is that the root part of can be bent or broken.

In view of this, the present inventors have proposed an antenna in which a rod-shaped antenna element is detachably screwed to a mounting base, and the strength of the joint portion of the antenna element is sufficiently large so that the load of the antenna element is concentrated on the joint portion. We have developed an in-vehicle whip antenna that does not cause breakage even when added to

That is, in this antenna, a coil spring-shaped spiral member is attached to the outer peripheral surface of the lower end portion of the rod-shaped antenna element to form a male screw, and it is detachably connectable to a mounting base that is previously fixed to the vehicle body wall. It is a thing.

According to this antenna, the whip material having high rigidity can be used as it is as a core without using a conventionally used joint, and the base end portion of the rod-shaped antenna element can be directly coupled to the mounting base. Therefore, the whip's original high rigidity,
Since the high elasticity can be used as it is, the strength of the joint portion is large, and the conventional defects can be improved.

[Problems to be Solved by the Invention] However, in the vehicle-mounted whip antenna developed by the present inventor, the following problems to be solved remain.

If a conventional female screw is used as the female screw on the mounting base side, there is a problem that the male screw made of a coil spring-shaped spiral member provided on the antenna side and the above female screw are not well-fitted with each other, and it is difficult to perform stable and tight screw coupling. It was

The present invention has been made in view of the above circumstances, and the object thereof is to include a coil spring-shaped spiral member provided on the antenna side, as well as being capable of screwing with a conventional male screw without any trouble. An object of the present invention is to provide a mounting base for a vehicle-mounted whip antenna, which has good compatibility with a male screw, enables stable and tight screw coupling, and has a female screw that can be easily manufactured.

[Means for Solving the Problems] The present invention has taken the following means in order to solve the above problems and achieve the object.

That is, a coil spring-shaped spiral member is mounted in a mounting hole of a mounting base body that is previously fixed to a vehicle body wall to form a female screw, and a conventional male screw provided at the lower end of a rod-shaped antenna element as well as a conventional male screw A male screw formed of a coil spring-shaped spiral member attached to the outer peripheral surface of the lower end portion is configured to be screwed.

[Operation] By taking such means, the following operation occurs.

When the male screw made of the coil spring-shaped spiral member on the antenna side is screwed into the female screw made of the coil spring-shaped spiral member on the mounting base side, the above-mentioned screws are elastically deformed to each other, and sufficient "familiarity" is given to the screw connection part. Occurs.
Therefore, stable and tight screw connection is possible. Further, since the female screw on the side of the mounting base is formed of a coil spring-shaped spiral member, the conventional screw processing is not required, and the manufacturability is improved, and the end of the spiral member can be used as it is as an antenna feed line connecting terminal. Since it is possible, it is not necessary to specifically provide the above-mentioned terminal, and the manufacturing can be facilitated also in this respect.

Even if a conventional machined external thread is used as the external thread on the antenna side, it can be screwed without trouble as long as the pitch relationship between both threads is appropriately set.

[Embodiment] FIG. 1 is a side sectional view showing the construction of an embodiment of the present invention. Reference numeral 14 denotes a mounting base body that is fixed in advance to a vehicle body wall (not shown). At the center of the mounting base body 14, a cylinder body 15 for forming a mounting hole H of the body 14 is provided. A spiral member S formed by winding in a coil spring shape is attached to the inner peripheral surface of the cylindrical body 15,
16 make up. One end Sa of the spiral member S is fixed to the inner surface of the cylindrical body 15 by welding, and the other end Sb is led out to the outside through the central hole of the closing body 17 that closes the lower end opening of the cylindrical body 15 to connect the antenna. It is designed to function as a wire connection terminal.

FIG. 2 is a diagram showing an example of use of the whip antenna mounting base configured as described above. In the figure, 11 is a rod-shaped antenna element formed of, for example, a single high tensile strength stainless steel rod. The rod-shaped antenna element 11 may be of a type in which a plurality of conductive pipes having different diameters are slidably connected to each other. A skirt-shaped attachment / detachment operation member 12 is attached near the lower end of the rod-shaped antenna element 11. A spiral member R formed by winding a wire in a coil spring shape is attached to the outer periphery of the antenna element at a position lower than the attachment position of the attachment / detachment operation member 12,
The external thread 13 is formed. The male screw 13 is formed to match the size of the female screw 16 of the mounting base.

Next, the operation of the present embodiment configured as described above will be described. A male screw provided at the lower end of the rod-shaped antenna element 11.
The 13 is attached to the female screw 16 on the mounting base side by screwing as shown by the arrow in FIG. Then, male screw
13 is screwed into the female screw 16. At this time, in the spiral member S forming the internal thread 16, only one end Sa is fixed to the tubular body 15 and the other parts are attached in a substantially free state.
In the process of being screwed into the
The spiral members will become compatible with each other. By this fitting, the strain existing between the spiral members is absorbed and removed. As a result, even if there is a slight dimensional error or variation in the spiral pitch between the male screw 13 and the female screw 16, the two are screwed into a tight state with no rattling. Since the conventional thread cutting process is unnecessary, the manufacturability is excellent. Further, since one end Sb of the spiral member S forming the female screw 16 can be used as an antenna feed line connecting terminal, the structure is simplified and the easiness of manufacture is improved.

FIG. 3 is a modification of FIG. As shown in FIG.
The male screw 13 is provided at a position slightly apart from the lower end of the antenna element 11, and the lower end 11a of the antenna element 11 where the male screw 13 does not exist is attached to the lower end small-diameter portion 15a of the cylindrical body 15 in the mounting base 14.
It is designed to be tightly inserted and supported. Although not shown, the lower end portion of the spiral member S is reduced in diameter to match the diameter of the small diameter portion 15a, and the antenna element 1
The lower end of 1 may be tightly inserted. By doing so, there is an advantage that a gap is not generated between the lower end portion of the antenna element 11 and the spiral member S having a reduced diameter.

It should be noted that, in place of the male screw 13, a conventional male screw, that is, a male screw formed by cutting a joint is used, and when this is screwed with the female screw 16, it is even possible to appropriately set the pitch relationship between the two. Then, it was found that the screws could be screwed together without any trouble.

The invention is not limited to the embodiments described above. For example, in the above embodiment, as shown in FIG. 4, the spiral pitch p of the spiral member S forming the internal thread 16 is set to be about twice the wire diameter d, that is, p≈2d, and the male screw 13 is formed in the gap between the wire rods. The case where the spiral member R is inserted and screwed is shown. However, as shown in FIG. 5, the wire diameter d of the spiral pitch p of the spiral member S forming the female screw 16 is substantially equal to p≈d. The spiral member R forming the male screw 13 may be screwed onto the inner peripheral side of the spiral member S in a state of being displaced by p / 2 from the spiral member S. Furthermore, as shown in FIG.
The spiral member R on the male screw 13 side may be screwed into the spiral member S on the female screw 16 side in an intermediate dimensional relationship between FIG. 4 and FIG.

In the above embodiment, the spiral member S is attached to the mounting base body 14.
The mounting hole H for fixing and holding the shaft in a non-rotatable and non-removable state has been exemplified by the cylindrical body 15. However, as shown in FIG. 7, the mounting base body 14 is directly provided with the hole 18, and The hole 18 may be used as the mounting hole H. Further, as shown in FIG. 8, in the process of molding the mounting base body 14 by molding with a material 19 such as a synthetic resin so as to surround the spirally wound spiral member S, the mounting hole H is formed.
May be formed at the same time.

In the above embodiment, the spiral member S has a cylindrical coil spring shape as shown in FIG. 9, but the rectangular tubular coil spring shape SS as shown in FIG. 10 may be used. Good.

In the above-mentioned embodiment, the wire member of the spiral member S has a circular cross section as shown in FIG.
A rectangular cross section as shown in FIG. 11 (b) and an elliptical cross section as shown in FIG. 11 (c) may be used.

Of course, various modifications can be made without departing from the scope of the present invention.

[Advantages of the Invention] According to the present invention, a coil spring-shaped spiral member is attached to the inside of the attachment hole of the attachment base body that is fixed in advance on the vehicle body wall to form a female screw, which is provided at the lower end of the rod-shaped antenna element. The male screw of the coil type is attached to the outer peripheral surface of the lower end of the same element, and the male screw made of a coil spring-shaped spiral member can be screwed, so that the screwing with the conventional male screw provided on the antenna side is hindered. Of course, it fits well with a male screw consisting of a coil spring-shaped spiral member, allows stable and tight screw coupling, and has a female screw mounting base for mounting a whip antenna that can be easily manufactured. Can be provided.

[Brief description of drawings]

1 to 3 are views showing an embodiment of the present invention, FIG. 1 is a side sectional view showing the structure of a whip antenna mounting base, and FIG. 2 is a view showing an example of use of the same embodiment. 3 is the second
It is a figure which shows the modification of a figure. 4 to 11 (a)
(B) (c) is a figure which shows the modification of each component. First
FIG. 12 is a diagram showing a conventional example. 11 …… Bar antenna element, 12 …… Detachable operation member, 13 ……
Male screw, 14 …… Mounting base body, 15 …… Cylinder body, 16 ……
Female thread, R, S ... Helical member, H ... Mounting hole.

Claims (2)

[Scope of utility model registration request] 1. A coil spring-shaped spiral member is mounted in a mounting hole of a mounting base body fixed in advance to a wall of a vehicle body to form a female screw so that a male screw provided at a lower end portion of a rod-shaped antenna element can be screwed. In-vehicle whip antenna mounting base characterized by being configured. 2. A coil spring-shaped spiral mounted on the outer peripheral surface of the lower end of a rod-shaped antenna element by mounting a coil spring-shaped spiral member into a female screw in a mounting hole of a mounting base body fixed in advance to a vehicle body wall. An in-vehicle whip antenna mounting base characterized in that a male screw made of a member is screwed together.