JP2647597B2 - Non-ceramic insulator gripping structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gripping structure at an end of a non-ceramic insulator which can be used for supporting a transmission line.

[0002]

2. Description of the Related Art Heretofore, it has been known that the end of a non-ceramic insulator is gripped as follows. That is, as shown in FIG. 4, a grip 13 having a sleeve 12 having a bottomed tubular shape is fitted into an end of a rod 11 formed of fiber reinforced resin (FRP). The open end of the sleeve 12 is crimped to the rod 11 by the crimping force of the crimping jig 14, whereby the rod 11 is gripped and fixed to the gripping metal 13.

[0003]

However, this gripping structure plastically deforms beyond the elastic limit of the sleeve 12 by the pressing force of the caulking jig 14 and at the same time elastically deforms the rod 11 housed in the sleeve 12. After the pressing force of the caulking jig 14 is removed, the inner surface of the sleeve 12 that has been plastically deformed and the rod 11 that is compressed and elastically deformed on the inner surface are based on the surface pressure due to the elastic repulsive force. A frictional force is generated to obtain a gripping force. Therefore, if the crimping force of the caulking jig 14 is strong, the rod 11 may exceed the elastic limit and break at the time of crimping, or may be damaged by stress concentration at the crimping portion. There is a problem that the rod-shaped body 11 is easily detached from the sleeve 12 due to a tensile force during use, because a sufficient surface pressure cannot be obtained.

The present invention has been made in view of the above-mentioned problems of the prior art, and has an object to reduce the possibility that a rod-shaped body will fall out of a gripping metal or be broken at a pressure-bonded portion, and the fatigue property will be reduced. An object of the present invention is to provide a non-ceramic insulator gripping structure which is excellent in durability and has improved durability.

[0005]

In order to achieve the above object, a non-ceramic insulator gripping structure according to the present invention provides a rod-shaped body made of fiber reinforced resin and a rubber insulating mantle provided on the outer periphery thereof. In the gripping structure of the non-ceramic insulator, which is formed by inserting a gripping member having a cylindrical shape with a bottom at the end of the rod-shaped body and crimping and crimping, at least an opening side of the inner peripheral portion of the gripping portion is crimped and crimped. is characterized in that interposed a cylindrical stress concentration relieving member made of a material to extend a region having a rod-shaped body and the same elastic properties.

[0006]

[Action] Caulking at least the opening side of the inner peripheral portion of the grip metal
The region spanning the crimping stress concentration relieving member made of a material having the same elastic properties and the rod-shaped member is interposed. Therefore, when the gripping jig is plastically deformed by the caulking jig and the rod-shaped body is elastically deformed, the stress concentration relieving body is also elastically deformed. As a result, the amount of elastic deformation is increased by the interposition of the stress concentration relieving body. but it becomes, which results in widening the control range of the crimping contact pressure.

The surface pressure between the rod and the stress concentration alleviating body is determined by the elastic limit of the rod, but the choice of increasing the friction coefficient can be made, and the apparent gripping metal
Since the amount of caulking increases and the rod does not directly contact the metal gripping metal with different characteristics such as elastic modulus, the concentration of stress on the rod in this part is eased, and the rod is stable. Is gripped by the gripping metal with the strong gripping force.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, a non-ceramic insulator 1
Is a rubber-made insulating mantle 3 on the outer periphery of a cylindrical rod-shaped body 2.
Are integrally provided. The rod-shaped body 2 is made of a fiber-reinforced resin, and as the fiber, a glass fiber, an aromatic polyamide fiber, or a cloth woven of these fibers is used. As the resin, a polyester resin, an epoxy resin, or the like is used. This fiber reinforced resin has an extremely high tensile strength. As the rubber constituting the insulating mantle 3, rubber having good weather resistance such as silicone rubber, ethylene-propylene copolymer rubber (EP rubber) is used. Note that the rod-shaped body 2 and the insulating mantle 3 may be integrally formed or formed separately and joined.

A grip 5 having a tubular sleeve 4 with a bottom is fitted into the end of the rod 2. The holding metal member 5 is formed of a plastically deformable material such as aluminum, iron, and stainless steel. This sleeve 4
A cylindrical stress concentration alleviating member 6 is fitted to an open end of the inner peripheral portion of the cylindrical member. The stress concentration relieving body 6 is formed of the same material as the material forming the rod-shaped body 2, and the contained fiber extends in the length direction like the rod-shaped body 2. It is preferable that the thickness of the stress concentration relieving body 6 is thicker, because the stress concentration of the rod-shaped body 2 in this portion is more relieved. The outer periphery of the opening end side of the sleeve 4 is caulked with a caulking jig 7 and the sleeve 4 is pressed against the rod-shaped body 2, whereby the end of the rod-shaped body 2 is gripped by the grip metal 5.

In this embodiment, a stress concentration relieving body 6 made of the same material as the rod 2 is interposed at the opening end side of the inner peripheral portion of the sleeve 4. In general, rods 2
When a tensile force is applied to the rod-shaped body 2 in the gripping metal member 5 for gripping the same, the largest stress concentration is likely to occur near the boundary between the rod-shaped body 2 made of FRP and the metal gripping metal member 5. However, in this embodiment, since the stress concentration relieving body 6 made of FRP having the same characteristics as the rod 2 is interposed in that portion, the elastic modulus at the boundary between the rod 2 and the stress concentration relieving body 6 is increased. Abrupt deformation based on the difference is unlikely to occur. Therefore, stress concentration hardly occurs in the portion where the stress concentration relieving body 6 is interposed, that is, the stress concentration is reduced.

For example, when a rod 2 having a diameter of 19 mm is used, the rod 2 is broken by a force of 20 to 24 tons (about 50% of the theoretical breaking strength of FRP) in the prior art. In this case, the breaking strength was improved to 28 to 30 tons (60% or more of the theoretical breaking strength of FRP).

Therefore, the rod 2 is gripped by the gripping metal 5 with a stable and strong gripping force. As a result, there is little possibility that the rod-shaped body 2 comes out of the gripping metal 5 when the crimping force of the caulking jig 7 is weak, or that the rod-shaped body 2 is broken at the crimped portion when the crimping force is strong. Further, fatigue characteristics of the rod-shaped body 2 due to repeated load, vibration and the like are improved, and the durability thereof is improved.

The present invention is not limited to the above embodiment, but may be embodied and configured as follows, for example, without departing from the spirit of the invention. (1) As shown in FIG. 3, the stress concentration relieving body 6 is provided over the entire inner peripheral surface of the sleeve 4. In addition, the length of the stress concentration alleviator 6 is appropriately adjusted according to the size of the insulator 1 and the like. (2) Making a cut in a part of the stress concentration alleviating body 6,
To provide an annular groove. (3) The stress concentration relieving body 6 is formed separately from the sleeve 4,
This is to be assembled in the sleeve 4 when the bar 2 is assembled.

[0015]

As described in detail above, according to the present invention,
It is possible to widen the control range of the crimping force of the gripper.
In this case, the rod-like body is less likely to fall out of the gripping metal or break at the pressure-bonded portion, and has excellent effects of excellent fatigue characteristics and improved durability.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a gripping structure of a rod-shaped body and a grip according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view showing another example of the present invention.

FIG. 4 is a cross-sectional view showing a conventional gripping structure between a rod-shaped body and a gripping metal.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Non-ceramic insulator, 2 ... Bar-shaped body, 3 ... Insulated mantle, 5 ... Grasping bracket, 6 ... Stress concentration relieving body.

Claims (1)

(57) [Claims] 1. A rod-shaped body formed of a fiber-reinforced resin and a rubber insulating mantle provided on an outer periphery thereof.
In a non-ceramic insulator gripping structure in which a bottomed cylindrical gripping metal is inserted into an end of the rod-shaped body and crimped and pressed, at least an opening side of an inner peripheral portion of the gripping metal is crimped and pressed.
Gripping structure of non ceramic insulator, wherein said that the interposed rod-like member and the tubular made of a material having the same elastic properties of the stress concentration relieving member in a region over which the.