Patent · US Expired

Breathing apparatus

US4964404A · kind A · utility

55Cited by
30References
42Claims
0Family size

Inventor

Key dates

Filing dateApr 19, 1989
Grant dateOct 23, 1990
Priority date
Expiry dateApr 19, 2009

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB63C11/24
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A mixed gas breathing apparatus reversibly switchable between open circuit and closed circuit systems. Three embodiments show three different levels of redundancy: nonredundant, bi-linear redundant and fully redundant. The counterlung minimizes the static lung loading and thus decreases breathing resistance. Manual control system is readily accessible and allows control of addition of the breathing gases.

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