Method for production of a pole part of a medium-voltage switching device, as well as the pole part itself

Abstract

A method for production of a pole part of a medium-voltage switching device, and a pole part are provided. To obviate costly pressure reinforcements at least on the switching contact side of the vacuum interrupt chamber in the area of the mold core, while also achieving an optimum injection-molded result, a compensation ring is positioned, before the encapsulation process, as a separate injection-molded seal on or close to the external circumferential line of a vacuum interrupt chamber cover, between the lower cover of the vacuum interrupt chamber and the mold core. The positioned compensation ring is also encapsulated so as to remain in the encapsulation, and the mold core is then removed.

Claims

1. A method for production of a pole part of a medium-voltage switching device, in which a vacuum interrupt chamber is provided with an insulating encapsulation by which the vacuum interrupt chamber is encapsulated together with a mold core having an annular portion, which is fitted to the vacuum interrupt chamber on a lower cover of the vacuum interrupt chamber, in a casting mold using an insulating material, the method comprising: before the encapsulation process, positioning a compensation ring as a separate injection-molded seal on or close to an external circumferential line of a vacuum interrupt chamber cover of the vacuum interrupt chamber, between the lower cover of the vacuum interrupt chamber and the mold core, the compensation ring contacting the annular portion of the mold core; encapsulating the vacuum interrupt chamber so that the positioned compensation ring remains in the encapsulation; and removing the mold core.

2. The method as claimed in claim 1, wherein the mold core that is used in the production process is composed of hardened steel.

3. The method as claimed in claim 2, wherein the compensating ring which is used as the injection molded seal in the production process is composed of copper or a copper alloy.

4. The method as claimed in claim 2, wherein the compensating ring which is used as the injection-molded seal in the production process is composed of aluminum or an aluminum alloy.

5. The method as claimed in claim 1, wherein the compensating ring which is used as the injection molded seal in the production process is composed of copper or a copper alloy.

6. The method as claimed in claim 1, wherein the compensating ring which is used as the injection-molded seal in the production process is composed of aluminum or an aluminum alloy.

7. The method as claimed in claim 1, wherein the compensation ring which is used as the injection-molded seal in the production process is composed of temperature-resistant and pressure-resistant plastic.

8. The method as claimed in claim 7, wherein the temperature-resistant and pressure-resistant plastic is configured to withstand injection-molding temperatures and injection-molding pressures.

9. The method as claimed in claim 1, wherein the compensation ring is positioned between a circumference of the vacuum interrupt chamber and the vacuum interrupt chamber cover on a switching contact side of the vacuum interrupt chamber.

10. The method as claimed in claim 1, wherein the compensation ring is positioned to abut a stepped portion arranged on a wall of the vacuum interrupt chamber.

11. A pole part for a medium-voltage switching device, in which a vacuum interrupt chamber is provided with insulation encapsulation, the pole part comprising: a compensation ring arranged for temporary contact with an injection-mold core on a cover face of the vacuum interrupt chamber to which the injection-mold core is temporarily applied for the encapsulation process, wherein the compensation ring is arranged to remain in the complete encapsulation, wherein the compensation ring is positioned to abut a stepped portion arranged on a wall of the vacuum interrupt chamber.

12. The pole part as claimed in claim 11, wherein the compensation ring is composed of copper or a copper alloy.

13. The pole part as claimed in claim 11, wherein the compensation ring is composed of aluminum or an aluminum alloy.

14. The pole part as claimed in claim 11, wherein the compensation ring is composed of temperature-resistant and pressure-resistance plastic.

15. The pole part as claimed in claim 14, wherein the temperature-resistant and pressure-resistant plastic is configured to withstand injection-molding temperatures and injection-molding pressures.

16. The pole part as claimed in claim 11, wherein the arranged compensation ring enables a cover of the vacuum interrupt chamber to be completely surrounded by the injection-mold core and not loaded during the injection process.

17. The pole part as claimed in claim 11, wherein the compensation ring is positioned between the vacuum interrupt chamber and a cover of the vacuum interrupt chamber on a switching contact side of the vacuum interrupt chamber.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Additional refinements, advantages and features of the present disclosure are described in more detail below with reference to exemplary embodiments illustrated in the drawings, in which:

(2) FIG. 1 shows an exemplary pole part with a mold part inserted, and a compensation ring according to at least one embodiment of the present disclosure; and

(3) FIG. 2 shows an enlarged perspective view of an exemplary features of the embodiment illustrated in FIG. 1.

DETAILED DESCRIPTION

(4) Exemplary embodiments of the present disclosure obviate costly pressure reinforcements at least on the switching contact side of the vacuum interrupt chamber in the area of the mold core, and also achieve an optimum injection-molded result.

(5) According to an exemplary method for producing a pole part, before the encapsulation process, a compensation ring is positioned as a separate injection-molded seal on or close to the external circumferential line of the vacuum interrupt chamber cover in the region of the cylindrically designed ceramic on the end surface, between the lower cover of the vacuum interrupt chamber. The mold core is then also encapsulated such that it remains as a lost seal in the encapsulation. The mold core is then removed again. According to an exemplary embodiment, the compensation ring reduces the load on the vacuum interrupt chamber during the injection-molding process.

(6) According to an exemplary embodiment, the mold core that is used in the production process can be composed of hardened steel, for example. According to this exemplary embodiment, the use of the compensation ring achieves the desired load reduction, such as when using the ring between ceramic and the steel core, for example.

(7) According to an exemplary embodiment, the compensation ring which is used as the injection-molded seal in the production process can be composed of copper or a copper alloy, for example. A suitable softer material is thus chosen.

(8) According to another exemplary embodiment, the compensation ring which is used as the injection-molded seal in the production process can be composed of aluminum or an aluminum alloy, for example.

(9) According to another exemplary embodiment, the compensation ring which is used as the injection-molded seal in the production process can be composed of temperature-resistant and pressure-resistant plastic, which withstands known injection-molding temperatures during the known injection-molding pressures.

(10) An exemplary embodiment of the present disclosure is illustrated in FIGS. 1 and 2, where FIG. 2 illustrates constituent elements within the dotted line box of FIG. 1 in more detail. According to the exemplary embodiment illustrated in FIGS. 1 and 2, a compensation ring 4 can be inserted, before the encapsulation process, between the mold core 6 and the ceramic insulator (end surface) 3 of the vacuum interrupt chamber 1. The compensation ring 4 acts as a mold seal in the insert part (the vacuum interrupt chamber 1) and dissipates the axial forces exerted on the vacuum interrupt chamber 1 via the ceramic 3 to the mold core 6. According to an exemplary embodiment, the compensation ring 4 can be composed of a material which does not damage the soldered metal-ceramic junction between the cover 5 on the switching contact side of the vacuum interrupt chamber 1 and the ceramic 3, or the ceramic 3 itself. For example, the compensation ring 4 can be constituted by relatively soft metals such as aluminum, an aluminum alloy, copper or a copper alloy. In accordance with another exemplary embodiment, the compensation ring 4 can be constituted by plastic materials as well, where such plastic materials are temperature and pressure-resistant to injection-molding temperatures and injection-molding pressures during the injection-molding process. It is advantageous for the ring and the pole part, which can be produced by injection molding, for example, to be composed of the same material, or at least compatible materials (in this context, the term “compatible” means that the parts adhere to one another). The exemplary compensation ring 4 can then remain in the pole part after the injection-molding process. According to an exemplary embodiment, the mold core 6 which is used in the production process can be composed of hardened steel. The exemplary compensation ring 4 achieves a desired load reduction, such as when using the compensation ring 4 between the ceramic 3 of the vacuum interrupt chamber on the switching contact side, and a mold core 6 constituted by the hardened steel.

(11) In the exemplary embodiment illustrated in FIGS. 1 and 2, a pole part of a medium switching device can be produced, in which a vacuum interrupt chamber 1 is provided with an insulating encapsulation. For example, the vacuum interrupt chamber 1 can be encapsulated together with a mold core 6, which is fitted to the vacuum interrupt chamber 1 on its lower cover, in a casting mold using an insulating material. According to the exemplary embodiment, before the encapsulation process, a compensation ring 4 is positioned as a separate injection-molded seal on or close to an external circumferential line of the vacuum interrupt chamber cover 5, between the lower cover of the vacuum interrupt chamber 1 and the mold core 6. The positioned compensation ring 4 is then encapsulated such that it remains as a lost seal in the encapsulation (i.e., it remains as positioned after the encapsulation process is completed), and then the mold core 6 is removed. According to the exemplary embodiment, a pole part for a medium-voltage switching device is provided, in which a vacuum interrupt chamber is provided with insulation encapsulation. As illustrated in FIGS. 1 and 2, the exemplary pole part includes a compensation ring 4 arranged for temporary contact with the injection-mold core 6 on a cover face of the vacuum interrupt chamber to which the injection-mold core 6 is temporarily applied for the encapsulation process. The compensation ring 4 is thus arranged so that it remains in the completed encapsulation.

(12) An advantageous aspect of the exemplary embodiment can be summarized as follows:

(13) The cover of the vacuum interrupt chamber is completely surrounded by the mold core 6 and is not loaded during the injection process. As a result, there is accordingly no need to reinforce the cover on the switching contact side. Accordingly, the cover of the vacuum interrupt chamber may therefore only need to be appropriately reinforced on the fixed contact side.

(14) It will be appreciated by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricted. The scope of the invention is indicated by the appended claims rather than the foregoing description and all changes that come within the meaning and range and equivalence thereof are intended to be embraced therein.

REFERENCE SYMBOLS

(15) 1 Vacuum interrupt chamber 2 Injection-molded plastic material 3 Ceramic of the vacuum interrupt chamber on the switching contact side 4 Compensation ring 5 Cover on the switching contact side of the vacuum interrupt chamber 6 Mold core