JPS60130022A - Self-recovery type current limiting element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Jin's invention relates to a self-healing forming flow element using a current limiting member.

A conventional one is shown in FIGS. 1 and 2. In the figure,
(1) is a cylindrical metal container, (2) is a through hole (2a)
A seat (3) is an insulating cylinder having through holes (3a), and a plurality of the through holes (8a) are arranged one on top of the other in the container (1) so that the through holes (8a) communicate with each other. (4) is an insulating cylinder having a through hole (4a) smaller than the through hole (8a);
a) They are arranged one on top of the other so as to communicate with the through hole (3a). (5)-(6) are shock absorbing members having through holes (5a) (6a) larger than each through hole (8a) (4a), and each through hole (8a) (4a) (5a) (6a). ) are arranged between each insulating cylinder (3) (4) so that they communicate with each other,
Each insulating cylinder (31 (4) provides a buffer between each other. (7) is an electrode having a through hole (7a), and the through hole (7a) is connected to each through hole (8a) (4a) (5a) (6a). (8) is a set screw screwed into one end of the container (1), which connects the electrode (7) via an insulator (9) to be described later.
) is pressed against the insulating cylinder (4). (9) is a container (1)
and the insulating cylinder (3) (
4) An insulator that firmly connects the buffer members (5) (6) and the locking screw 8), preferably one made by mixing mica and galanu powder with a binding material and sintering it. (10 is an electrode having a through hole (10a), which is screwed onto the other end of the container (1) so that the through hole (10a) communicates with the through holes (8a), (4a), (5a), and (6a). The α force is the container (
1) a gasket that seals between the electrode H, and (to) a piston that is slidably disposed within the through hole (10a);
The sliding surface is sealed with a seal. (I41 is a nut screwed onto the electrode (+1), which prevents the electrode 0Q from loosening. aυ is a plug that seals the through hole (7a) of the electrode (7), and is screwed onto the electrode (7). The ring is a plug that seals the through hole (10a) of the electrode 00, and is screwed onto the electrode (11).
, 8a) (4a) (5a) (6a) (7a) The current limiting member is filled with alkali metals such as sodium or potassium. θ mark is piston (2) and aα
An inert gas such as argon gas is used in the pressure buffer filled in the through hole (10a) between the two.

In the above configuration, when an overcurrent flows between both electrodes (7) H, the α force of the current limiting member in the small cross-sectional area inside the through hole (4a) of the insulating cylinder (4) is vaporized first. Then, the other portions of the current limiting member aη are vaporized and become plasma. Since the generated plasma has high resistance, both electrodes (
7) The overcurrent between α is limited to a predetermined value or less, and is finally cut off by a switch (not shown).

On the other hand, the high vapor pressure generated by vaporizing the current limiting member (IM) is buffered by the piston (2) compressing the pressure buffer 08.Then, after the current is cut off, the vaporized current limiting member αη is cooled and further liquefied or solidified by the back pressure of the pressure buffer zero barrel to restore the normal state.

Further, after current limiting, a predetermined circuit voltage is applied between both electrodes (7) B*, but this insulation is maintained by an insulator (9).

By the way, when high-temperature plasma is generated, the insulation cylinder (31
The portions of the through holes (8a) (4a) of (4) melt and wear out, but most of these melts are deposited in the through holes (6a) of the buffer member (6). However, if the number of current limiting operations becomes frequent or the operating time becomes long, the conductive buffer member (6) may melt and the through holes (8a ) (4a) and becomes conductive, which has the disadvantage that when an overcurrent flows thereafter, the prescribed current limiting action cannot be performed.

In this invention, at least one of the buffer members arranged between the insulating cylinders is composed of a first spacer made of an insulating material and a second spacer made of a metal arranged on both sides of the first spacer. By making the through holes of both spacers larger than the through holes of the insulating cylinder, the amount of melting of the second spacer is reduced, and the amount of intrusion into the through hole of the insulating cylinder can be reduced, which reduces the number of operations and the operation time. To provide a self-contained current limiting element that can be expanded.

The figures will be explained below. In FIGS. 8 and 4, (1) to (5) and (7) to (g) are the same as the conventional one.

01 is a first spacer made of an insulator placed between the insulating tubes (3), between the insulating tubes (3) (4), and between some of the insulating tubes (4); 3) (4)
Through hole (i9a) larger than (8a) (4a)
is provided.

The first spacer H is suitably made of a material having a high melting point, high thermal conductivity, and alkali resistance, such as beryllia porcelain or alumina porcelain. (stomach)
are spacers arranged on both sides of the first spacer 0 and are 4 times smaller than the first spacer α, and are made of a metal such as a copper plate and have a through hole (20
a) is provided.

Note that both spacers αI (a) constitute a Wm portion M&f). Therefore, the second spacer (a) acts as a buffer when sintering the insulator (8), and the insulating cylinder (3)
(4) The spacing between both spacers is the buffer part 1 consisting of α field)
1. It is formed by Q.

Next, the effect will be explained. In FIG. 8 and the fourth cause, if an excessively high current flows between the electrodes (7) 09, the current limiting member (17)
) vaporizes and becomes a high-temperature, high-resistance plasma that limits the current. At this time, as shown in Table 1E, the first spacer a
The melting point of Beliar porcelain is approximately 2500°C, which is more than twice that of conventional copper spacers, so even if the second copper spacer (1) melts, the melting point is approximately 2500°C. Because of the small amount, it is not possible to make the through holes (8a) (4a) of the insulating cylinders (3) (4) conductive.

Table 1 Therefore, the number of operations and the service life from the operation time are determined by the degree of wear and tear on the through holes (8a) (4a) of the insulating cylinders (3) (4).

According to this invention, the buffer member is constituted by a first spacer made of an insulating material and a second spacer made of metal arranged on both sides of the first spacer, and the through hole of both spacers is formed by the through hole of the insulating tube. The larger the spacer, the less the melted weight of the conductive second spacer, which can extend its life.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a conventional self-return type current limiting element, a cross-sectional view showing one embodiment, and FIG. 4 is a cross-sectional view showing the main part of FIG. 3. In the figure, (3) and (4) are insulating tubes, (8a) (
4a), (19a), and (20a) are through holes, θ is a first spacer, ■ is a second spacer, and Qp is a buffer member. Note that the same reference numerals in each figure indicate the same or equivalent parts. Agent Masuo Oiwa

Claims (3)

[Claims] (1) The current limiting member is connected alternately so that the first through hole of the insulating cylinder and the second through hole of the buffer member communicate with each other, and the current limiting member is vaporized by an overcurrent and has a current limiting effect. At least one of the buffer members is filled in each through hole and returns the current limiting member to a steady state after the overcurrent disappears.
a first spacer made of an insulating material and a second spacer made of metal disposed on both sides of the first spacer, and the second through hole is larger than the first through hole. A self-healing forming flow element characterized by: (2) The self-restoring forming flow element according to claim 1, wherein the eleventh spacer is made of Beliar porcelain. (3) The self-restoring current limiting resistor according to claim 1, wherein the first spacer is made of alumina porcelain.