Artificial respiration ventilator of air constant flow

• US 4,635,631 A
• Filed: 10/29/1984
• Issued: 01/13/1987
• Est. Priority Date: 11/04/1983
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Izumi, Kazuo
• Primary Examiner(s): Recla, Henry J.
• Application Number:
  US06/666,248
• Time in Patent Office: 806 Days
• Field of Search: 128/204.21, 128/204.23, 128/204.24, 128/204.25
• US Class Current: 128/204.23
• CPC Class Codes: A61M 16/00 Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes stimulating the respiratory movement by mechanical, pneumatic or electrical means, iron lungs combined with gas breathing means A61H31/00
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 16/204 used for inhalation control
• CPC Class Codes: A61M 16/205 used for exhalation control
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor

Abstract

A respiratory circuit for an artificial inspiration ventilator is characterized in that it controls a volume of an O2/air constant flow as being substantially reversely proportional to a positive and negative airway pressures by patient'"'"'s own respiration. The respiratory circuit comprises a pressure sensor for detecting an inner pressure of the respiratory circuit, a comparator for comparing the inner pressure with reference values prescribed by reference voltages, and a switching circuit responsive to the results of the comparator for switching a valve passing the O2/air constant flow.

Claims

1. An artificial respiration ventilator for controlling the volume of continuous air flow passing into a patient'"'"'s lungs comprising:

respiratory circuit means for conducting a continuous air flow from a source to a patient'"'"'s lungs during inhalation and exhalation phases of a respiratory cycle;

sensing means for sensing a generation of positive and negative airway pressures in the respiratory circuit means caused by inhalation and exhalation efforts;

means for generating a plurality of threshold signals corresponding to predetermined positive and negative airway pressure threshold value

threshold detection means, responsive to said sensing means, for ascertaining when said sensed positive and negative airway pressures exceed said threshold values;

means for generating a plurality of reference input signals corresponding to a plurality of air volume flow rate values;

switching means, responsive to said threshold detection means, for choosing one from a plurality of reference input signals when one of the plurality of threshold values is exceeded; and

air volume flow rate adjusting means, responsive to the output of said switching means, for continuously and instantaneously adjusting the air volume flow rate through the respiratory circuit means in accordance with the reference input value chosen by said switching means such that the continuous air flow through substantially inversely proportioned to the sensed positive and negative airway pressures.

2. The artificial respirator ventilator of claim 1, wherein said sensing means senses the positive and negative airway pressures by referring to a change in inner pressure of said respiratory circuit means.

3. The artificial respiration ventilator of claim 1 wherein said air volume flow rate adjusting means increases the air volume flow rate through the respiratory circuit means if the sensed negative airway pressure exceeds a first threshold value and wherein said air volume flow rate adjusting means further decreases the air volume flow rate through the respiratory circuit means if the sensed positive airway pressure exceeds a second threshold value.