Disconnecting device for a surge arrester

Abstract

The invention relates to a disconnecting device for a surge arrester which is accommodated by a support body, and wherein plug contacts which are connected to at least one arrester element of the surge arrester extend from the support body. The invention further comprises a switching tongue which is connected at a first end to the arrester element via a thermal separating point and with a second end to one of the plug contacts. Furthermore, a spring-preloaded insulating disconnecting bracket which is pivotably mounted on the support body is provided, the spring preload acting on the thermal separating point via the switching tongue. According to the invention, the switching tongue is configured as a straight-surface, elongated, metallic, resiliently elastic disconnecting strip having a rectangular cross-section.

Claims

1. A disconnecting device for a surge arrester which is accommodated by a support body, and wherein plug contacts which are connected to at least one arrester element of the surge arrester extend from the support body, further comprising a switching tongue which is connected at a first end to the arrester element via a thermal separating point and with a second end to one of the plug contacts, a spring-preloaded insulating disconnecting bracket which is pivotably mounted on the support body, the spring preload acting on the thermal separating point via the switching tongue, wherein the switching tongue is configured as a straight-surface, elongated, metallic, resiliently elastic disconnecting strip having a rectangular cross-section, a connection to a contact surface of the arrester element being made by means of the thermal separating point via the broadside of a first disconnecting strip end, and a connection to one of the plug contacts being made via a circumference of a second disconnecting strip end which plunges into a slot-shaped recess within a section of the plug contact which faces the support body, the recess being substantially complementary to a cross-sectional area of the second disconnecting strip end, and the disconnecting bracket being further subject to a shift in position when a melting point of the thermal separating point is reached, and thus lifting the disconnecting strip with the first disconnecting strip end thereof from the contact point, and the disconnecting bracket entering a resulting gap.

2. The disconnecting device according to claim 1, wherein the disconnecting bracket is configured as a rotary lever.

3. The disconnecting device according to claim 1, wherein a guiding lug is integrally formed with the support body to accommodate the second disconnecting strip end.

4. The disconnecting device according to claim 1, wherein the second disconnecting strip end is soldered or welded to the plug contact.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

(1) FIG. 1 shows a perspective view of a plug-in part of a surge arrester without outer housing and without lower part, but with outer electrical screw connecting terminals in the operational, i.e. not disconnected state;

(2) FIG. 2 shows a representation similar to that shown in FIG. 1, but in the disconnected state, wherein here, the disconnecting bracket has already shifted in position and plunged into the gap between the contact point and the disconnecting strip;

(3) FIG. 3 shows a detailed view for forming the connection of one of the plug contacts via the circumference of a second disconnecting strip end, which plunges into a slot-shaped recess within a section of the plug contact which faces the support body.

DETAILED DESCRIPTION OF THE INVENTION

(4) The disconnecting device according to the invention in accordance with the example embodiment may be part of a surge arrester in the form of a plug-in part, as indicated in FIGS. 1 and 2.

(5) Here, the shown plug-in part does not yet have an outer housing in order to make the design and function of the disconnecting device clear.

(6) The plug-in part has a support body 1, which on one side includes a chamber-like recess having at least one arrester element.

(7) The support body has an opening 2, which allows access to a contact point 3 of the arrester element.

(8) The thermal separating point known per se is realized in this area.

(9) Furthermore, the support body 1 has a curved guide 4 to accommodate a spring 5 which generates a preload force. It should also be noted that the spring 5 is supported at one end on a stop of an insulating disconnecting bracket 6 which is formed as a rotary slide.

(10) The rotary slide is located on a axis of rotation 7, which may be configured as an extension and thus as an integral element of the support body 1.

(11) External connections of the surge arrester can be configured as plug contacts 8; 9, which engage in U-shaped mating contacts 10 and 11.

(12) The mating contacts 10 and 11 are connected to or are part of external connection screw terminals 12 and 13 known per se.

(13) According to the invention, the switching tongue of the thermal separating point is configured as a straight-surface, elongated, metallic, resiliently elastic disconnecting strip 14.

(14) The connection to the contact surface 3 of the arrester element is made, as explained, by means of the thermal separating point, more specifically via the broadside of a first disconnecting strip end 140.

(15) In contrast thereto, the connection to one of the plug contacts 9 is made via the circumference of a second disconnecting strip end 141, which plunges into a slot-shaped recess 15 in an extension section 16 of the plug contact 9.

(16) Here, the recess 15 corresponds substantially to the cross-sectional area of the second disconnecting strip end 141 and is configured so as to be complementary to this end.

(17) A corresponding detailed representation can be seen in FIG. 3.

(18) When the melting point of the thermal separating point is reached, the disconnecting bracket 6 is subject to a shift in position; this can be seen in FIGS. 1 and 2 by a movement to the left.

(19) The first disconnecting strip end 140 of the disconnecting strip lifts off from the contact point 3. Furthermore, the area 60 of the disconnecting bracket 6 enters the resulting gap (see FIG. 2).

(20) The shift in position of the disconnecting bracket 6 can be seen through an inspection window not shown in the figures in an outer housing not shown which encloses the support body 1.

(21) In this respect, a display surface 61 is integrally formed with the disconnecting bracket 6.

(22) As shown in FIGS. 1 and 2, the disconnecting bracket 6 is formed as a rotary slide. At its edge 62 facing the thermal separating point, the disconnecting bracket 6 may have a flattening in the form of a bevel or wedge surface to optimize the penetration into the separating point area and the disconnecting process.