Patent · US Expired

N.sub.2 tunnel freezer

US4783972A · kind A · utility

32Cited by
8References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 29, 1987
Grant dateNov 15, 1988
Priority date
Expiry dateOct 29, 2007

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF25D2317/0681
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

A cryogenic freezer having a thermally insulated tunnel-like enclosure with an entrance and an exit and means for conveying products being frozen therethrough. Products are contacted with liquid cryogen at a region generally near the entrance and a blower located closer to the entrance than to the exit controls flow of cryogen vapor. Upstream and downstream baffles and dampers associated with blower are linked together for complementary movement to selectively regulate the upstream and downstream flow of vapor discharged from the blower. Additional blowers circulate the cold cryogenic vapor transverse to the direction of the conveying means. The temperature of vapor leaving the region of the entrance is monitored the orientation of the baffle and damper arrangement is adjusted in accordance with the temperature monitored. The food products can be contacted by liquid nitrogen in a reservoir facilitates cleaning and retards inefficient vaporization.

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