Patent · US Expired

Distortion free dewar/coldfinger assembly

US4952810A · kind A · utility

4Cited by
5References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 23, 1989
Grant dateAug 28, 1990
Priority date
Expiry dateAug 23, 2009

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF17C2270/0509
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An infrared detector assembly (10) of the type used in munitions and night vision systems having an improved coldfinger assembly (42). Such detector assemblies (10) include a tubular coldfinger (22) which is surrounded by a vacuum and an end-cap (28) mounted to the coldfinger tube (22) to define a cold end (24) which supports the infrared detector array (30) and related components. In accordance with this invention, the coldfinger tube (22) is a thin-walled titanium cylinder and the end-cap (28) is made of tungsten. The components are metallurgically bonded at the cold end (24) by an active brazing alloy deposited during vacuum furnace brazing. The titanium coldfinger (22) provides the necessary bending stiffness to support cold end components. The tungsten end-cap (28) provides a low distortion, thermally stable focal-plane. The metallurgical bond (46) provides for a hermetic seal which inhibits structural distortion during brazing, and during cyclical cooling of the detector assembly (10).

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