Surge Arrester With Moulded Sheds And Apparatus For Moulding

Patent metadata

Field	Value
Publication number	US-2016284447-A1
Application number	US-201315033042-A
Country	US
Kind code	A1
Filing date	Nov 5, 2013
Priority date	Nov 5, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

A high voltage surge arrester including insulating polymer housing with a protruding shed. The shed has an upper shed surface that forms a blunt angle with the longitudinal axis of the surge arrester and a lower shed surface. The lower shed surface includes an inner portion that forms an essentially right angle with said axis and an outer portion that forms an acute angle with said axis. Further the invention relates to an apparatus for moulding an electrically insulating polymer housing.

First claim

1 . A high voltage surge arrester ( 10 ) comprising a varistor element ( 20 ) surrounded by an electrically insulating polymer housing ( 30 ) with a protruding shed ( 40 ), said shed ( 40 ) having an upper shed surface ( 50 ) that forms a blunt angle ( 55 ) with the longitudinal axis (z) of the surge arrester ( 10 ) and a lower shed surface ( 60 , 70 ), characterised in that the lower shed surface comprises
an inner portion ( 60 ) that forms an essentially right angle ( 65 ) with said axis (z) and an outer portion ( 70 ) that forms an acute angle ( 75 ) with said axis (z).

2 . The high voltage surge arrester ( 10 ) of claim 1 , wherein the peripheral free end of the shed ( 40 ) comprises a straight section ( 80 ) that extends essentially in parallel with the longitudinal axis (z) of the surge arrester ( 10 ).

3 . The high voltage surge arrester ( 10 ) of claim 2 , wherein said straight section ( 80 ) extends along more than half the peripheral free end thickness of the shed ( 40 ).

4 . The high voltage surge arrester ( 10 ) of claim 2 or 3 , wherein said straight section ( 80 ) is level with said inner portion ( 60 ) of the lower shed surface.

5 . The high voltage surge arrester ( 10 ) of any preceding claim, wherein the lower shed surface comprises one single inner portion ( 60 ) and one single outer portion ( 70 ).

6 . The high voltage surge arrester ( 10 ) of any preceding claim, wherein the inner portion ( 60 ) of the lower shed surface constitutes 20-80% of the shed extension.

7 . The high voltage surge arrester ( 10 ) of any preceding claim, wherein the outer portion ( 70 ) of the lower shed surface constitutes 20-80% of the shed extension.

8 . The high voltage surge arrester ( 10 ) of any preceding claim, wherein said blunt angle ( 55 ) is equal to or larger than 92°.

9 . The high voltage surge arrester ( 10 ) of claim 8 , wherein said blunt angle ( 55 ) is equal to or smaller than 103°.

10 . The high voltage surge arrester ( 10 ) of any preceding claim, wherein said acute angle ( 75 ) is equal to or smaller than 88°.

11 . The high voltage surge arrester ( 10 ) of claim 10 , wherein said acute angle ( 75 ) is equal to or larger than 81°.

12 . The high voltage surge arrester ( 10 ) of any preceding claim, wherein said essentially right angle ( 65 ) is 89-91°.

13 . An apparatus for moulding an electrically insulating polymer housing ( 30 ) with protruding sheds ( 40 ), which apparatus comprises a first mould part ( 110 ) and a second mould part ( 150 ) which when brought together form a mould half ( 100 ) for a shed ( 40 ), wherein said first mould part ( 110 ) comprises a first mould surface ( 120 ) that is essentially evenly inclined for forming an upper shed surface ( 50 ) and said second mould part ( 150 ) comprises a second mould surface ( 160 , 170 ) for forming a lower shed surface ( 60 , 70 ), characterised in that the second mould surface ( 160 , 170 ) comprises
an inner mould surface ( 160 ) that is essentially perpendicular to the rotational axis (z) for forming an inner portion ( 60 ) of the lower shed surface and an outer mould surface ( 170 ) that is inclined with respect to the inner mould surface ( 160 ) for forming an outer portion ( 70 ) of the lower shed surface.

14 . The apparatus of claim 13 , wherein the first and second mould parts ( 110 , 150 ) comprise respective contact shoulders ( 130 , 180 ) which are adapted to form a tight seal when the mould parts ( 110 , 150 ) are brought together, and wherein the inner corners ( 140 , 190 ) of said contact shoulders ( 130 , 180 ) are right-angled or blunt.

15 . The apparatus of claim 13 or 14 , wherein the first and second mould parts ( 110 , 150 ) comprise respective contact shoulders ( 130 , 180 ) which are adapted to form a tight seal when the mould parts ( 110 , 150 ) are brought together, and wherein the contact shoulder ( 180 ) of the second mould part ( 150 ) is level with the inner mould surface ( 160 ).

Assignees

• Abb Technology Ltd

Inventors

• Johansson Daniel
• Gustavsson Christian
• Lindberg Eija
• Faxö Elisabeth

Classifications

• B29L2031/3481

  Housings or casings incorporating or embedding electric or electronic elements · CPC title

• B29C33/44

  with means for, or specially constructed to facilitate, the removal of articles, e.g. of undercut articles · CPC title

• H01B19/00

  Apparatus or processes specially adapted for manufacturing insulators or insulating bodies {(manufacture of porcelain for electric insulation C04B33/26)} · CPC title

• H01C7/12 Primary

  Overvoltage protection resistors; Arresters · CPC title

• B29C33/3842

  Manufacturing moulds, e.g. shaping the mould surface by machining · CPC title