Patent · US Expired

Method for making low pressure mercury vapor discharge lamp

US4725298A · kind A · utility

1Cited by
4References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 12, 1986
Grant dateFeb 16, 1988
Priority date
Expiry dateMay 12, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J9/26
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A low pressure mercury vapor discharge lamp forms an electric discharge path by the use of a bulb placed on an end plate and the bulb is formed by a process which results in the connecting outer side surfaces of juxtaposed glass tubes through communication holes formed in the outer side surfaces respectively. The process involves placing the juxtaposed glass tubes so that their outer surfaces are opposed in a contacting state. A portion of each of the glass tubes is heated in order to form a communication hole through the utilization of a burner inserted through an open end into the interior of each of the glass tubes in order to cause fusion of that particular portion in each tube to thereby form the communication hole by wind pressure. A mass of molten glass is then forced outward at the outer peripheral edge of the communication hole whereby these outer peripheral edges of the glass tubes are mutually connected by the mass of molten glass and the open end of the tubes are then closed to form a U-shaped passage between the tubes.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.