The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 17, 1984
Filed:
Sep. 13, 1982
Stanley E Fry, Riverside, CA (US);
Bear Medical Systems, Inc., , CA (US);
Abstract
A mechanism is provided for a respiratory ventilator by which the gas-delivery mechanism of the ventilator can be caused to deliver gas to the patient either at a predetermined flow rate or at a rate directly controlled by the patient's instantaneous demand. The mechanism includes a pressure-responsive device adapted to produce an analog signal indicative of the difference between a reference pressure and the patient's airway proximal pressure. The analog signal has a first polarity when the proximal pressure is less than the reference pressure in response to an inhalation effort, and a second polarity when the proximal pressure is greater than the reference pressure in response to an exhalation effort. A first control mechanism is provided which causes the gas-delivery system to deliver gas at a rate which is proportional to the absolute value of the analog signal when the signal has the first polarity and an absolute value at least equal to a predetermined threshold value. The control mechanism responds to the second polarity of the analog signal by causing the gas-delivery system to recharge itself with a fresh supply of gas. The same gas-delivery mechanism can also be operated in an assist mode to deliver gas at a predetermined flow rate by a second control mechanism responsive to the analog signal.