ELECTRICAL LAMP

摘要

An electric lamp has a lower bowl portion formed as two semicircular halves, over part of which an Edison lamp cap is screwed. The two bowl halves have identical helical rib portions, the cross-section of each rib portion having a height and length selected so that the lamp cap thread fits over them, engaging top edges of ribs on one bowl half and the lower edges of the ribs on the other bowl half.