The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 05, 1984
Filed:
Nov. 22, 1982
Applicant:
Inventors:
Gary L Eesley, Lake Orion, MI (US);
Jeffrey C Buchholz, Detroit, MI (US);
Jeffery A Sell, Huntington Wood, MI (US);
Assignee:
General Motors Corporation, Detroit, MI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01N / ; G01M / ;
U.S. Cl.
CPC ...
73 52 ; 73 493 ; 73705 ; 356361 ;
Abstract
Tungsten halogen lamps require a fill pressure of several atmospheres. To verify the fill pressure at the time of manufacture the pressure is indirectly measured by first measuring the speed of sound within the lamp. A shock wave is produced within the lamp by rapidly heating a lamp filament or producing an arc between two adjacent filaments and measuring the time required for the shock wave to sequentially disturb two spaced light beams passing through the lamp. The speed of sound is determined from the measured time and the pressure is calculated from the speed of sound.