Expedient refinements and advantages are the subject matter of the following description, with reference to the figures of the drawing, in which components which have the same effect are provided with the same reference symbols, and in which:
FIG. 1 shows a perspective illustration of one exemplary embodiment of the dielectric housing according to the invention,
FIG. 2 shows the dielectric housing shown in FIG. 1, in a perspective plan view from above, and
FIG. 3 shows a plan view of the dielectric housing from underneath, thus showing the interior of the housing.
FIG. 1 shows one exemplary embodiment of the dielectric housing 1 according to the invention, in the form of a perspective illustration. The dielectric housing 1 has an essentially hollow-cylindrical holding section 2, and a truncated-conical drive section 3, which is adjacent to the holding section in a longitudinal direction and has an internal diameter which is larger than that of the holding section 2. A holding sleeve 4, in which an input connecting piece 5 composed of copper is encapsulated, is formed at the upper end of the holding section 2. In order to attach a vacuum interrupter tube, which is not illustrated in the figures, a mounting opening 6 is provided behind the holding sleeve 4, through which the vacuum interrupter tube can be screwed to the input connecting piece 5.
A holding sleeve 7 is likewise integrally formed on the drive section 3, and an outgoer connecting piece 8 is encapsulated in it. The retention as well as the electrical connection of a vacuum interrupter tube to the input connecting piece 5 or to the outgoer connecting piece 8 result in a solid-insulated switch pole. The input connecting piece 5 is intended for connection to a high-voltage line, which is at a voltage of 10 to 50 KV with respect to the ground potential. When the vacuum interrupter tube is switched on, the outgoer connecting piece is also at the high-voltage potential. External ribs 10 are used to lengthen the creepage distance between an end piece 9, which is at ground potential, and the dielectric housing 1.
The holding section 2 merges in places over a transition shoulder 11 into the drive section 3. In contrast, a ventilation shaft 12 can be seen in the rear part of the dielectric housing 1, and its inlet opening is formed in the transition area between the drive section 3 and the holding section 4. In this case, the external contour of the drive section 3 is continued without any discontinuity by means of the circumferentially outer boundary surface of the ventilation shaft 12, so that transition shoulders 11 are avoided in the area of the ventilation shaft 12. In other words, the boundary wall of the ventilation shaft 12 continues the external contour of the drive section 3 continuously and without any steps. The ventilation shaft 12 surrounds more than half of the cylindrical holding section 3, with holding rods 14 being provided for mechanical robustness of the ventilation shaft 12.
FIG. 2 shows the dielectric housing from FIG. 1, in the form of a perspective illustration from above. As can be seen, the input connecting piece 5 extends beyond the mounting opening 6, thus allowing subsequent connection of the vacuum interrupter tube by a screwing action. An attachment rib 15 can also be seen, which is intended to provide robustness for the dielectric housing 1 or the solid-insulated switch pole when this is assembled with further switch poles arranged adjacent to it to form a switch. In this case, each switch pole is intended to switch one phase of a three-phase power supply system.
FIG. 3 shows the interior of the dielectric housing 1 in a plan view of the underneath of the dielectric housing 1. As can seen, the dielectric housing 1 is firmly screwed in the end piece 9 through holes 16. As can also be seen, the transition shoulder 11 is formed in the front area, while the ventilation shaft 12 extends effectively through a cutout in the transition shoulder 11 in the upper area. The two narrow faces 13 of the ventilation shaft 12 cover an angle of more than 180 degrees with respect to a center point 15 of the holding section 2. As can also be seen, the ventilation shaft 12 tapers towards its outlet opening remote from the end piece 9, thus making it possible to produce a chimney effect, which increases the cooling power. Once the vacuum interrupter tube has been installed in the holding section 2, heat is produced in the interior of the drive section 3, in particular at the level of the outgoer connecting piece 8, that is to say underneath the intake opening of the ventilation shaft 12. This heat is produced in particular at a moving contact connection, which provides the electrical link between the switching rod (which is guided such that it can move) of the vacuum interrupter tube and the stationary outgoer connecting piece. By way of example, a moving contact connection such as this has one or more flexible strips, a sliding contact, a rolling contact or the like. The increased amount of heat developed at the moving contact connection is a result of the increased electrical contact losses. The arrangement of the moving contact connection precisely underneath the intake opening of the ventilation shaft 12 allows the rising heat to enter the ventilation shaft directly, thus considerably increasing the cooling power. The invention avoids labyrinth-like flow paths of the air, as in the prior art.
Patent Application
20080078664
