Joseph F Gregory

US Patent:

45538530, Nov 19, 1985

Filed:

Feb 27, 1984

Appl. No.:

6/584072

Inventors:

Joseph D. Gregory - Casanova VA
James M. Budnik - Essex Junction VT

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G01N 2510

US Classification:

374 25

Abstract:

A monitoring technique is disclosed for determining when the end point has been achieved in the evaporation of the constituents from an alloy such as a tin lead alloy. An optical pyrometer or other temperature sensing device, is focused on a crucible in which both tin and lead is being heated. Since, under vacuum conditions, lead evaporates at a lower boiling point than does tin, the temperature of the crucible will achieve a first temperature plateau while the lead is being evaporated. After the lead has been depleted in the crucible, the temperature of the crucible will rise to a higher temperature plateau at which the tin will evaporate. The output of the optical pyrometer is digitized and is applied to a microcomputer which periodically samples the temperature of the crucible. The microcomputer is programmed to identify the lower boiling plateau for the lead constituent, to detect the rise in temperature of the crucible after the lead has been depleted, and to recognize the higher boiling point plateau for the tin constituent. The microcomputer will then output a signal to turn off the heating source to the crucible when the temperature of the crucible is detected to rise after the second, higher boiling point plateau for the tin.

Address:

3059 Ebbtide Dr, Edgewood, MD 21040

Phone:

4106760651

VIN:

KMHCN36C97U026130

Make:

HYUNDAI

Model:

ACCENT

Year:

2007