Arc chamber for a low-voltage switching device

Patent metadata

Field	Value
Publication number	US-2021241981-A1
Application number	US-201817048699-A
Country	US
Kind code	A1
Filing date	Apr 19, 2018
Priority date	Apr 19, 2018
Publication date	Aug 5, 2021
Grant date	—

Abstract

An arc chamber 10, 20, 30, 40, 50 for a low voltage switching device comprising an insulating casing 1, having a first and a second lateral walls 2,3, a rear and a front wall 4,5, that defines an internal space housing a number of arc-breaking plates, a top wall 6 of said casing having a discharge opening 101 for venting off the gases from said internal space, said discharge opening 101 being covered by a top cover 7, 37, 47, 57. The arc chamber for a low voltage switching device comprises a filter 11, 21, 31, 41, 51 made of an open cell metal foam is positioned at said discharge opening 101.

First claim

1 . An arc chamber for a low voltage switching device comprising an insulating casing ( 1 ), having a first and a second lateral walls a rear and a front wall, that defines an internal space housing a number of arc-breaking plates, a top wall of said casing having a discharge opening for venting off the gases from said internal space, said discharge opening being covered by a top cover, and a filter made of an open cell metal foam is positioned at said discharge opening.

2 . The arc chamber for a low voltage switching device, according to claim 1 , wherein said filter made of an open cell metal foam covers entirely said discharge opening.

3 . The arc chamber for a low voltage switching device, according to claim 1 , wherein said open cell metal foam of said filter has a porosity of greater than 70%, preferably greater than 80%, more preferably greater than 85%.

4 . The arc chamber for a low voltage switching device, according to claim 3 , wherein said open cell metal foam of said filter has a thermal conductivity of lower than 15 W·m −1 ·K −1 .

5 . The arc chamber for a low voltage switching device, according to claim 4 , wherein said open cell metal foam of said filter has a tensile strength of greater than 5 MPa.

6 . The arc chamber for a low voltage switching device, according to claim 5 , wherein said open cell metal foam of said filter is provided with a structure having randomly distributed channels.

7 . The arc chamber for a low voltage switching device, according to claim 6 , wherein said filter made of an open cell metal foam is interposed between said discharge opening and said top cover.

8 . The arc chamber for a low voltage switching device, according to claim 7 , further comprising a perforated sheets positioned between said filter made of an open cell metal foam and said discharge opening, a spacer interposed between said perforated sheets and said filter made of an open cell metal foam, said top cover being superimposed onto said filter made of an open cell metal foam.

9 . The arc chamber for a low voltage switching device, according to claim 1 wherein said filter made of an open cell metal foam is inserted into said top cover.

10 . The arc chamber for a low voltage switching device, according to claim 1 , wherein said filter made of an open cell metal foam is integrally made within said top cover.

11 . The arc chamber for a low voltage switching device, according to claim 1 , wherein said top cover is entirely made with said filter made of said open cell metal foam.

12 . A low voltage switching device comprising an arc chamber according to claim 1 .

13 . The arc chamber for a low voltage switching device, according to claim 1 , wherein said open cell metal foam of said filter has a thermal conductivity of lower than 15 W·m −1 ·K −1 .

14 . The arc chamber for a low voltage switching device, according to claim 1 , wherein said open cell metal foam of said filter has a tensile strength of greater than 5 MPa. cm 15 . The arc chamber for a low voltage switching device, according to claim 1 , wherein said open cell metal foam of said filter is provided with a structure having randomly distributed channels.

16 . The arc chamber for a low voltage switching device, according to claim 1 , wherein said filter made of an open cell metal foam is interposed between said discharge opening and said top cover.

17 . The arc chamber for a low voltage switching device, according to claim 1 , further comprising a perforated sheets positioned between said filter made of an open cell metal foam and said discharge opening a spacer interposed between said perforated sheets and said filter made of an open cell metal foam, said top cover being superimposed onto said filter made of an open cell metal foam.

18 . The arc chamber for a low voltage switching device, according to claim 13 , wherein said open cell metal foam of said filter has a thermal conductivity of lower than 12 W·m −1 ·K −1 .

19 . The arc chamber for a low voltage switching device, according to claim 14 , wherein said open cell metal foam of said filter has a tensile strength of greater than 10 MPa.

20 . The arc chamber for a low voltage switching device, according to claim 3 , wherein said open cell metal foam of said filter is provided with a structure having randomly distributed channels.

Assignees

• Abb Spa

Inventors

• Arrighetti Pierantonio
• Antoniazzi Antonello
• Adami Alessandro
• Torresin Daniele
• Agostini Francesco

Classifications

• H01H73/18

  Means for extinguishing or suppressing arc {(magnet coil acting as blow-out device H01H71/38)} · CPC title

• H01H2009/347

  using lids for closing the arc chamber after assembly · CPC title

• H01H9/342 Primary

  Venting arrangements for arc chutes · CPC title