JPH0115207Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a rod antenna in which a plurality of conductive rods of different diameters are slidably connected to each other. Concerning improvements in the means for holding

[Technical background of the invention and its problems]

In conventional rod antennas of this type, the spring force of a conductive elastic body was used to establish an electrical connection between the two rods as a means of elastically holding the inner rod at a predetermined position on the outer rod. Therefore, in order to obtain sufficient elasticity, it is necessary to increase the thickness of the spring portion of the conductive elastic body or increase the number of spring portions.

However, if the thickness of the spring portion is increased, it will not be possible to fit the inner and outer rods together smoothly during assembly, and a great deal of labor will be required. Furthermore, if the number of spring parts is increased, the structure of the conductive elastic body becomes complicated, making it difficult to process and increasing the cost. Moreover, in any of the cases described above, since an elastic member made of metal such as phosphor bronze is used, sliding movement during expansion and contraction may occur due to dimensional variations in the component parts during processing or assembly. There was a problem that it was difficult to carry out the process smoothly.

[Purpose of invention]

The purpose of the present invention is to provide a rod antenna that can stably and reliably hold the inner rod in a predetermined position, is easy to assemble, can be manufactured at low cost, and can perform smooth sliding motion. There is a particular thing.

[Summary of the idea]

In order to achieve the above object, the present invention is characterized by the following structure. That is, in a rod antenna in which a plurality of conductive rods of different diameters are slidably connected to each other, a conductive elastic body is attached to the outer periphery of the base end of the inner rod, and this conductive elastic body is attached to the outside adjacent to the inner rod. Make sure that it comes into pressure contact with the inner peripheral surface of the rod. On the other hand, an insulating elastic body is attached to the inner circumferential surface of the tip of the outer rod so that this insulating elastic body comes into pressure contact with the outer circumferential surface of the inner rod adjacent to the outer rod. The insulating elastic body has an inner diameter smaller than the outer diameter of the inner rod in at least a portion (for example, the central portion), and has a slit along the direction parallel to the axis, and has a slit along the outer periphery of the inner rod. A pressurizing cylinder part is provided which presses against the surface and elastically supports the inner rod. Thus, by providing means for elastically holding the inner rod at a predetermined position of the adjacent outer rod separately from the means for electrically connecting the inner and outer rods, the disadvantages of the conventional method are eliminated.

[Example of idea]

FIG. 1 is a sectional view of essential parts showing an embodiment of the present invention. That is, numerals 10 and 20 in FIG. 1 indicate a pair of inner and outer rods in a rod antenna in which a plurality of conductive rods of different diameters are slidably connected to each other. A conductive elastic body 30 made of, for example, a thin piece of phosphor bronze is attached to the outer periphery of the proximal end of the inner rod 10. One end of this conductive elastic body 30 is pressed against the inner circumferential surface of the outer rod 20, thereby establishing an electrical connection between the inner rod 10 and the outer rod 20. Reference numeral 40 denotes a liner for preventing rattling, which is fixed to the outer periphery of the proximal end of the inner rod 10, leaving the area where the conductive elastic body 30 is attached. An insulating elastic body 50 is attached to the inner periphery of the tip of the outer rod 20.
This insulating elastic body 50 is shown in FIGS.
As shown in b, it is formed into a substantially cylindrical shape using a resin such as Diyuracon (trade name).

In FIGS. 2 and 3a and 3b, 51 is a pressurizing cylindrical portion that applies a required elastic force to the inner rod 10, and its inner diameter D1 is set to the inner rod 10 in order to obtain the required expansion stress. It is set slightly smaller than the outer diameter of 10. Large diameter cylinder parts 52a and 52b are connected to both ends of the pressure cylinder part 51.
The outer diameter D2 of the large diameter cylindrical portions 52a, 52b is set to be approximately the same diameter as the inner diameter of the outer rod 20. The pressurizing cylinder part 51 and the large diameter cylinder part 52a, 5
Tapered portions 53a and 53b are provided at the connecting portion with 2b so that the inner rod 10 can be smoothly inserted into the pressurizing cylinder portion 51. A pair of slits 54 and 55 are provided in the pressurizing cylinder part 51 and the tapered parts 53a and 53b, and the large diameter cylinder part 52
A and 52b have grooves 5 connected to the slits.
6a, 56b and 57a, 57b are provided, respectively. The slits 54, 55 and the groove 56
a, 56b, 57a, 57b to enhance the elasticity of the pressurizing cylinder part 51 and the large diameter cylinder parts 52a, 52b.

As described above, the insulating elastic body 50 configured as described above is fitted into the inner circumferential portion of the tip of the outer rod 20, and the large diameter cylindrical portions 52a and 52b are caulked, etc., thereby making the insulating elastic body 50 elastic. The body 50 is easily immobilized. When the inner rod 10 is inserted into the hollow part of the pressure cylinder part 51 of the insulating elastic body 50, the pressure cylinder part 51 has an outer diameter D1 slightly larger than the outer diameter of the inner rod 10 to be fitted therein. Since the diameter is set to be small and the slits 54 and 55 are provided, when the inner rod 10 is inserted, it is expanded as shown by arrows A and B in FIG. 2, and the stress is applied to the outer peripheral surface of the inner rod 10. Acts as a strong pressure force. Therefore, the inner rod 10 is the outer rod 20.
The position is held stably and reliably. In addition, since the insulating elastic body 50 is integrally molded from a resin material, it is easy to manufacture and can be manufactured at low cost, and there is little manufacturing variation and the rod can slide smoothly. Note that the purpose of the conductive elastic body 30 can be sufficiently achieved as long as it is electrically conductive and separated, so the contact pressure may be relatively small. Therefore, a single contact piece is sufficient and the thickness of the spring material may also be small. Therefore, manufacturing is easy and there is no risk of high cost.

The present invention is not limited to the one embodiment described above. For example, slits 54, 55, groove 56
The numbers of a, 56b, 57a, and 57b may be increased or decreased from those in the embodiment. It goes without saying that various other modifications can be made without departing from the gist of the present invention.

[Effect of idea]

According to the present invention, a conductive elastic body is attached to the outer periphery of the proximal end of the inner rod to press against the inner periphery of the outer rod, and at least a portion of the elastic member is attached to the inner periphery of the tip of the outer rod. An insulating elastic body has a small inner diameter, a slit along the direction parallel to the axis, and a pressurizing cylinder part that comes into pressure contact with the outer peripheral surface of the inner rod to elastically support the inner rod. Since the insulating elastic body can be used to stably and reliably hold the inner rod in a predetermined position, the assembly work is easy and can be manufactured at low cost. It is possible to provide a rod antenna that can perform dynamic operations.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of essential parts showing an embodiment of the present invention;
FIG. 2 is a perspective view of the insulating elastic body in the same embodiment, and FIGS. 3 a and 3 b are a sectional view and a front view of the same insulating elastic body. 10...Inner rod, 20...Outer rod, 3
0... Conductive elastic body, 40... Rattling prevention liner, 50... Insulating elastic body, 51... Pressure cylinder part,
52a, 52b...large diameter cylinder part, 53a, 53b...
...Tapered portion, 54, 55...Slit, 56a,
56b, 57a, 57b...grooves.

Claims (1)

[Scope of utility model registration request] In a rod antenna in which a plurality of conductive rods of different diameters are slidably connected to each other, the rod antenna is attached to the outer periphery of the proximal end of the inner rod of the rod antenna and is provided in pressure contact with the inner periphery of the outer rod adjacent to the inner rod. and an insulating elastic body attached to the inner periphery of the tip of the outer rod so as to be in pressure contact with the outer periphery of the inner rod adjacent to the outer rod, The insulating elastic body has an inner diameter smaller than the outer diameter of the inner rod, has a slit along a direction parallel to the axis, and presses against the outer peripheral surface of the inner rod to tighten the inner rod. What is claimed is: 1. A rod antenna comprising: a resiliently supported pressurizing cylinder; and a large diameter cylinder connected to both ends of the pressurizing cylinder and having a groove connected to the slit on its inner circumferential surface.