JPH0623051Y2 - Electric telescopic antenna device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an electric telescopic antenna device mounted on a vehicle.

[Prior Art] As an electric telescopic antenna device of this type, rack teeth are formed on a drive cord connected to a tip rod of a telescopic multistage antenna rod, and a drive gear is meshed with the rack teeth. It is known that the expanding / contracting multi-stage antenna rod is expanded / contracted by driving the gear.

The advantage of the above structure is that the drive gear is engaged with the rack teeth as compared to the drive cord wound around the winding drum and controlled by the winding / rewinding operation to control the expansion / contraction operation of the expansion / contraction multi-stage antenna rod. Since they work together, the push-up force is large and reliable feeding is possible, which is advantageous as measures against freezing and wind pressure during traveling.

[Problems to be solved by the invention]

However, even when using the above-described rack toothed drive cord, when the drive cord is wound around the drum or pushed out in a linear state due to the extension of the antenna rod, the material becomes brittle due to repeated bending loads. With this, the drive cord locally buckles,
Eventually, the rack teeth may be damaged, or the cord itself may be cut and other failures may occur. In particular, since the above antenna device is attached to a place exposed to the outside air, the drive cord is also affected by the outside air temperature, so that it is often used under conditions that are disadvantageous in terms of material and breaks during the long-term use. Sometimes. Then, when these are replaced due to damage to the antenna rod or breakage of the drive cord, the drive cord is pulled out from the outer end of the antenna housing cylinder together with the removal of the antenna rod.
There is a circumstance in which a broken or damaged part remains inside the device and it is extremely difficult to remove it. For this reason, the drive cord maintains its connected state as a whole even if the rack teeth are damaged or locally cut, and can be easily removed from the device during replacement. There is a need.

As a resin drive cord other than the electric telescopic antenna device, there is an example in which when a resin circular cross-section cord is extruded, it is made hollow and a metal single core such as a steel wire is inserted into this later. However, there is no cooperative effect between the single core and the wrapping material surrounding it, and the broken wrapping material may fall off the steel wire, which is not useful.

The present invention has been made based on the above circumstances, and even if local damage or disconnection occurs, the connection as a whole is maintained and the broken portion remains in the device when the drive cord is replaced. Therefore, the present invention aims to provide an electric telescopic antenna device in which the drive cord is structurally devised.

[Means for solving problems]

In order to achieve the above object, the electric telescopic antenna device of the present invention is connected to a distal end rod of the telescopic multistage antenna rod, and is configured to extend and retract the drive cord having rack teeth and the telescopic multistage antenna rod. And a drive gear that meshes with the rack teeth, wherein the drive cord includes a core material of a fiber assembly formed by knitting or twisting elastically rich high-strength materials with a synthetic resin foreskin material, and a tooth groove. Rack teeth for exposing the core material at the bottom are formed in the foreskin material.

[Action]

Therefore, even if the foreskin material becomes brittle, the central core material maintains sufficient strength, and even if the rack teeth are damaged or the foreskin material is cut, the entire drive cord is connected through the core material. The core material is maintained and, moreover, the core material is composed of an aggregate of knitted fibers or twisted fibers and is embedded at the same time when the foreskin material is extruded. ∙ The broken part does not fall off the core material. Therefore, when replacing the drive code,
The breakage portion is not left in the device, and there is no trouble of removing the breakage portion.

〔Example〕

Hereinafter, an embodiment of the present invention will be specifically described with reference to the drawings, regarding a drum retractable electric telescopic antenna device.

In the drawing, reference numeral 1 is a drive device housing, and an antenna housing cylinder 3 for housing the telescopic multistage antenna rods 2a, 2b, 2c is erected at one end thereof. Further, in the drive device housing 1, the tip rod 2a of the antenna rod is provided.
A cord storage free drum 5 is provided for the drive cord 4 connected to the. Further, guides 6 and 7 in which the drive cord 4 is wound around the free drum 5 are prepared. In the drive unit housing 1, there is further provided a drive gear 8 which rotates with the same axis as the free drum 5, which is a drive cord extended from the free drum 5 and extending toward the antenna housing cylinder 3. A guide roller 9 is provided which is engaged with the rack teeth 4a of No. 4 and prevents the engagement from being disengaged. Further, a motor housing 10 is mounted on the drive device housing 1, and a worm 12 is provided on a drive shaft of an electric motor 11 provided inside the drive device housing 1, and a worm wheel 13 in the drive device housing 1 is provided. It is meshed. And
The output transmitted from the worm 12 to the worm wheel 13 is transmitted to a counter gear 15 via a reduction gear train 14 and a clutch mechanism (not shown), and drives the counter gear 15 to output a pulse for controlling opening / closing of a motor power supply. A signal is output and transmitted to drive the drive gear 8 via the clutch mechanism.

As shown in FIGS. 2 and 3, the drive cord 4 has a core material 4b covered with a foreskin material 4c made of synthetic resin such as Duracon.
The above-mentioned rack tooth 4a is formed on one side of the rack tooth.
Part of the core material 4b is exposed in the tooth groove portion of 4a. The drive cord 4 is formed by extruding the foreskin material 4c with respect to the core material 4b by extruding the foreskin material, and then pressing the rack teeth 4a. In this case, the core material 4b is located at the center of the drive cord 4, and as a material, a material having elasticity and higher strength than the foreskin material 4c, for example, Kevlar fiber, which is a polyamide-based high-strength fiber, is knitted or twisted. An aggregate is used together. In this example, the Kevlar fiber has a specific gravity
About 1.45 and fiber diameter 0.012mm, so it has a tensile strength of 3
It can be an aggregate of about 70 kg / mm ² .

In such a configuration, when the drive gear 8 is normally or reversely rotated at the speed reduced by the reduction gear train 14 by the drive of the motor 11, the drive cord 4 pushes up or pulls down the tip rod 2a to the drum 5. Get involved.

In this case, in the drive cord 4, since the core material 4b is superior to the foreskin material 4c in elasticity and strength, it is localized due to breakage of the rack teeth 4a or embrittlement of the foreskin material 4c due to weather resistance. Even if the cutting occurs, the cooperation as the drive cord 4 can be maintained by the core material 4b. Therefore, replacement and repair becomes easy.

Further, the core material 4b has such a form that it passes through the center of the drive cord 4 and is locally exposed to the outside between the rack teeth 4a, and furthermore, it is integrally formed when the foreskin material 4c is molded. The adhesiveness with the foreskin material 4c is good, and the reinforcing effect can be exhibited. Also, no stress remains when bending or buckling. In other words, the bending force is repeatedly applied to the drive cord 4 in the process of winding it onto the drum 5 and pulling it out, but since the core material 4b is partially exposed, the entire outer circumference is exposed. Is not restrained by the foreskin material 4c, the stress can be dispersed by elastic deformation of the exposed portion and the durability against bending is high.

Since the tooth tips of the drive gear 8 come into contact with the exposed portion of the core material 4b, in order to increase the strength of this portion and improve the durability, at least with respect to the exposed portion of the core material 4b,
A coating film may be provided.

[Advantages of the Invention] The present invention has been described in detail above, and by improving the configuration of the drive cord, the durability of the core material against bending and buckling is improved, the cord strength is increased, and the foreskin material is improved. Even if the drive cord is damaged or cut, the core material can keep the entire drive cord connected, so the entire drive cord can be pulled out without leaving a cut portion etc. when repairing and replacing. It is possible to obtain practical effects such as being possible. In addition, since the foreskin material is partially divided by the rack teeth reaching the core material, the bending force acting at the time of winding, drawing, etc. is dispersed, and the durability of the drive cord is also improved.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the present invention in which a part is longitudinally cut, FIG. 2 is a side view of a drive cord, and FIG. 3 is a sectional view taken along the line III-III of FIG. 1 ... Drive housing, 2a, 2b, 2c ... Antenna rod,
4 ... drive cord, 4a ... rack teeth, 4b ... core material, 4c ... wrapping material, 5 ... lead drum, 8 ... drive gear.

Claims (1)

[Scope of utility model registration request] 1. A drive cord, which is connected to a tip rod of a telescopic multi-stage antenna rod and has rack teeth formed thereon, and a drive gear, which meshes with the rack teeth so as to extend and retract the telescopic multi-stage antenna rod. The drive cord includes a core material of a fiber assembly obtained by knitting or twisting a material having high elasticity and high strength with a wrapping material made of synthetic resin, and rack teeth for exposing the core material at the bottom of the tooth space. An electric telescopic antenna device formed on a foreskin material.