JPS6347214B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an operating rod of an operating mechanism or a support rod of a component such as a vacuum valve in a switching device such as a vacuum shield disconnector, an air disconnector, or the like. This relates to insulating rods used as

Technical Background of the Invention In general, in switching devices such as vacuum disconnectors, air disconnectors, etc., sufficient electricity is required between the electrically charged electrode opening/closing part and the non-electrode opening/closing mechanism part. It is necessary to be able to measure the mechanical movement required to open and close the electrodes while ensuring physical insulation. Moreover, it has sufficient mechanical strength to withstand mechanical stress such as mechanical movement, that is, impactive tensile force and compressive force that act during opening and closing operations, and impact bending load due to impactful transient vibrations. There needs to be. In recent years, in response to the demand for this type of insulating structure, a reinforcing shaft 1 is made of a round bar made by wrapping glass cloth and impregnating and hardening resin such as polyester or epoxy, as shown in Figures 1a and b. An insulating rod is generally used in which an epoxy resin 2 filled with silica particles or alumina particles is cast into a shape.

Problems with the Background Art By the way, this type of reinforced insulating rod needs to be mechanically connected to other movable parts at its end. Therefore, as shown in Fig. 2, a female thread 3 is machined at the shaft core end of the glass cloth laminated round bar serving as the reinforcing shaft 1.
A method is adopted in which the bolt member 4 or the like made of another metal material is fastened. Therefore, if the female thread of the glass cloth laminated round bar, which is the reinforcing shaft 1, is repeatedly subjected to shocking tensile and compressive forces that act during opening and closing operations, impact shearing stress will repeatedly act on the female thread of the glass cloth laminated round bar, which is the reinforcing shaft 1, and the female thread will become damaged. A problem occurs in which the bolt member 4 comes off due to impact fatigue failure of the mountain.

Purpose of the Invention In view of the above circumstances, an object of the present invention was made to eliminate the above-mentioned drawbacks. An object of the present invention is to provide an insulating rod whose permissible load is improved with respect to tensile, compressive and bending loads.

Embodiment of the Invention Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In Figures 3a and 3b, a square bar made by stacking glass cloth, impregnating it with epoxy resin, and hardening it under pressure is cut into the same width as the board thickness.The reinforcing shaft 5 is the center of the reinforcing shaft 5, and silica particles or alumina particles are used as the reinforcing shaft 5. The insulating rod is made by casting the epoxy resin 2 filled with the epoxy resin 2 into a pleated shape around the reinforcing shaft 5. At both ends of the laminated square bar serving as the reinforcing shaft 5, a female thread 3 is machined at the core end of the shaft, and as shown in Fig. 2, a metal male thread serving as a joint member such as a bolt member is screwed into the fastening method. It is configured so that it can be connected to other parts.

With the insulating rod having the above structure, the fatigue strength against the impact shear stress generated on the threads of the female thread 3 of the reinforcing shaft 5 due to the impact tensile force and compressive force that act during opening and closing operations is lower than that of the conventional laminated round rod. As shown in FIG. 4, this is greatly improved compared to an insulating rod using a rod as a reinforcing shaft. This is the case when a female thread is provided in the axial direction at the end of a laminated round bar made by laminating glass cloth around the axial center and hardened with resin as the conventional reinforcing shaft 1. As shown by the arrow, the above-mentioned impact shear stress acts on the laminated interface of the glass cloth, so there is almost no reinforcing hardening of the glass cloth fibers and the strength is extremely reduced. On the other hand, in the case of the present invention, in which a female thread is provided at the end of a laminated square bar made by laminating glass cloth, impregnating it with resin, and hardening it under pressure, a female thread is provided at right angles to the lamination direction of the glass cloth, as shown in FIG. As shown by the arrows in c and d, the surface on which the impact shear stress acts does not match the laminated interface of the glass cloth, so
The reinforcing effect of glass cloth fibers is fully recognized, and it shows extremely high strength. Laminated round bars are made by tightly wrapping glass cloth to impregnate and harden with resin, while laminated plates are made by stacking glass cloth, impregnating with resin, and hardening under pressure. Therefore, the laminated square bar has a larger value than the laminated round bar in terms of fatigue strength against repeated tension in the axial direction. Therefore, for insulating rods with the same cross section, it is possible to provide insulating rods with high reliability in terms of mechanical strength, even against impact tension and compressive loads during opening/closing operations, or against impact bending due to transient vibrations. can.

Although the present invention has been described above in the case of a pleated insulated operating rod, the present invention is not limited thereto. As other embodiments, for example, in the case of an insulated operating rod or an insulated support rod that does not require a long insulation distance, the laminated square rod may be machined with internal threads at both ends as shown in Fig. 6a and b, or the The same effect can be obtained even with an insulating rod having male threads cut at both ends so that it can be connected to a joint fitting member as shown in FIG. 6c.

Effects of the Invention As described above, according to the present invention, the insulating rod acts as an insulating operation rod or an insulating support rod in a switching device such as a vacuum disconnector, an air disconnector, etc. It has excellent fatigue strength characteristics against axial loads and impact bending loads due to transient vibrations, and also exhibits strong strength characteristics against tightening loads during assembly and other external forces.

[Brief explanation of drawings]

Figure 1a is a plan view of a conventional pleated cast insulating rod;
Figure b is a sectional view, Figure 2 is a sectional view showing the tightened state of the insulating rod and the fitting bolt, and Figure 3 a.
is a plan view of the insulation of the laminated rectangular rod reinforcement according to the present invention, FIG. , Figures 5 a to d are comparison diagrams of shear stress acting surfaces in laminated round bars and laminated square bars, and Figures 6 are a to d.
c is an explanatory diagram showing another example of application of the laminated square bar. 1... Reinforcement shaft (laminated round bar), 2... Cast material, 3... Female thread for connecting metal fittings, 4... Bolt member, 5... Reinforcement shaft (laminated square bar).

Claims (1)

[Claims] 1 Glass cloth is stacked in a multilayer structure in the same direction, impregnated with resin and cured under pressure, and the laminate is cut to have a rectangular cross section when viewed from the stacking direction to determine the stacking angle. An insulating rod characterized in that a rod is used as a reinforcing shaft, and at least one end of the reinforcing shaft is formed with a female thread for attaching a joint fitting in the axial (longitudinal) direction and perpendicular to the lamination direction.