Patent ID: 8058788

Claim:
In a lamp base ( 10 ) comprising: a shell ( 14 ), an eyelet ( 16 ) and an electrically-insulating glass part ( 18 ) therebetween and joining said shell ( 14 ) and said eyelet ( 16 ), said shell ( 14 ) and said eyelet ( 16 ) being electrically conductive, the improvement wherein: said shell ( 14 ) has a tubular portion ( 14 a ) with an open end ( 14 b ) and a partially closed end ( 14 c ) defining a volume ( 14 d ) therebetween, said partially closed end ( 14 c ) including a tapered area ( 14 e ) terminating in a reentrant section ( 14 f ) that comprises a continuous curve that extends into said volume ( 14 d ) and defines an inner annulus ( 14 g ) that projects toward said tapered area ( 14 e ) whereby said inner annulus ( 14 g ) has a diameter greater than the inner diameter of the reentrant section ( 14 f ) that is adjacent to said eyelet ( 16 ), said inner annulus ( 14 g ) and said reentrant section ( 14 f ) being free from glass flashing ( 140 h ) whereby no glass particles inhabit said volume.