JPS6234401Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a lightning arrester whose characteristic element is a voltage nonlinear resistance element whose main component is zinc oxide (ZnO).

In this type of lightning arrester, the desired operating voltage is ensured by the number of stacked elements, which are characteristic elements, but in order to obtain the desired discharge withstand capacity, the element area must be made large. However, when increasing the size of a voltage nonlinear resistance element, it shrinks by about 40% in volume during the firing process, and the distortion caused by this contraction tends to cause element cracking, and the voltage nonlinearity characteristics deteriorate due to the composition. Furthermore, heat dissipation efficiency also deteriorates, making it difficult to improve discharge durability.

Therefore, as shown in FIG. 1, three element blocks 1 ₁ , 1 ₂ , and 1 ₃ each stacked with small voltage nonlinear resistance elements have been conventionally installed in parallel in the insulator tube 2.
The element blocks ₁₁ to ₁₃ are assembled using electrode plates 3 for connecting the elements at the same potential position in parallel and support rods 4 for supporting the element blocks in the stacking direction, and then housed in the insulator tube 2. There is something.

This conventional structure facilitates the molding of elements with excellent characteristics and improves heat dissipation efficiency, but the element blocks 1 ₁ to 1 ₃
There is wasted space between the two, so to obtain the same discharge capacity, the diameter of the insulator tube must be increased. Furthermore, it requires assembly of element blocks and a coupling structure between elements.

The present invention was developed in view of the above circumstances, and is made by assembling several element pieces having fan-shaped flat surfaces into a circular shape, covering the outer circumferential surface with an elastic jacket, and expanding the element block within an insulator tube. The object of the present invention is to provide a lightning arrester that solves the conventional problems by having a structure in which each element is brought into close contact with the inner surface of the tube.

FIG. 2 is a plan view showing an embodiment of the present invention. The voltage non-linear resistance element is formed as one characteristic element by a combination of three fan-shaped element pieces 5 ₁ , 5 ₂ , 5 ₃ of the same shape, and its center part is removed, and the outer peripheral surface is covered with elastic material such as rubber. Moreover, it is assembled into a circular shape by the outer cover 6 having excellent insulating properties. A predetermined number of these elements are stacked in one cylindrical jacket 6 to form an element block, which is fitted into the insulator tube 7 with a slight play.

As shown in FIG. 3, the element block fitted into the insulator tube 7 is driven into the hollow part at its center by an expansible member 8 having excellent elasticity and insulation properties, so that each element piece is pushed toward the inner side of the insulator tube 7. It is pushed out and brought into close contact with the inner surface of the insulator tube 7, using the jacket 6 as a cushion.

Therefore, wasted space within the insulator tube is reduced, and heat is radiated from the element pieces through the insulator tube and by air convection through the gaps between the element pieces, making it possible to radiate heat sufficiently. Further, the assembly work is simple, that is, inserting the element block into the insulator tube and adhering it tightly to the insulator tube using the pushing and expanding member, and the support of the element is ensured by eliminating the need for a support rod or the like.

Note that the number of element pieces 5 ₁ to 5 ₃ is not limited to three, but two or four or more can be assembled into a circular shape, and the curvature of the element pieces depends on the inner diameter of the insulator tube including the outer jacket dimension. When configured together, the adhesion to the insulator tube becomes more effective, thereby ensuring heat dissipation and support.

As described above, according to the present invention, the efficiency of accommodating the elements in the insulator tube is improved, the discharge withstand capacity is improved, and the elements can be easily housed and assembled to provide reliable support. Also,
It has an electrode area equivalent to that of a large-sized element, which facilitates its manufacture and provides excellent element characteristics.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a conventional lightning arrester, and FIGS. 2 and 3 are plan views for explaining an embodiment of the present invention. 5 ₁ , 5 ₂ , 5 ₃ ... Voltage nonlinear resistance element, 6
...Outer cover, 7...Insulator tube, 8...Press expansion member.

Claims (1)

[Scope of utility model registration request] In a lightning arrester whose characteristic element is a voltage nonlinear resistance element whose main component is zinc oxide, a plurality of voltage nonlinear resistance element pieces with fan-shaped planes are assembled into a circular shape, and the outer peripheral surface of the element is covered with an elastic jacket. The device is characterized by comprising a block and a push-spreading member that is inserted into the center of the device block in order to push and spread the element pieces of the device block toward the inner side of the insulator tube in which the device block is housed. lightning arrester.