×

Servo-controlled demand regulator for respiratory ventilator

  • US 4,459,982 A
  • Filed: 09/13/1982
  • Issued: 07/17/1984
  • Est. Priority Date: 09/13/1982
  • Status: Expired due to Term
First Claim
Patent Images

1. A respiratory ventilator, of the type having breathable gas supply means, exhalation valving means, conduit means adapted for transmitting breathable gas to a patient during inhalation and for transmitting exhaled gas from said patient to said exhalation valving means, and gas-delivery means for alternately receiving gas from said gas supply means during exhalation and delivering said received gas to said conduit means during inhalation, wherein the improvement comprises:

  • first means for supplying a reference pressure;

    second means, receptive to said reference pressure and the pressure in said conduit means, for producing an electronic signal having a value indicative of the pressure differential between said first means and said conduit means, said electronic signal having a first polarity when the pressure in said conduit means is less than said reference pressure in response to an inhalation effort by said patient, and a second polarity when the pressure in said conduit means exceeds said reference pressure in response to an exhalation effort by said patient; and

    third means, responsive to said electronic signal, for (a) actuating said gas-delivery means so as to deliver gas to said conduit means at a rate which is substantially proportional to the absolute value of said electronic signal when said electronic signal has said first polarity and a predetermined threshold value indicative of at least a threshold level pressure differential, and (b) actuating said gas-delivery means so as to receive gas from said gas supply means either when said electronic signal has said second polarity or when said electronic signal remains approximately at said predetermined threshold value for a predetermined time interval, whichever first occurs.

View all claims
  • 5 Assignments
Timeline View
Assignment View
    ×
    ×