Humidifier and automatic control system therefor

• US 4,098,853 A
• Filed: 03/30/1976
• Issued: 07/04/1978
• Est. Priority Date: 03/25/1974
• Status: Expired due to Term

• Current Assignee: Allied Healthcare Products Incorporated
• Original Assignee: Chemetron (IL) Corporation (Newell Brands Inc.)
• Inventors: Brown, Allen C., Hattes, Neil R., Eyrick, Theodore B.
• Primary Examiner(s): Miles, Tim R.
• Assistant Examiner(s): Chiesa, Richard L.
• Application Number:
  US05/671,787
• Time in Patent Office: 826 Days
• Field of Search: 261/122, 261/DIG. 65, 261/64, 261/65, 261/123, 261/124, 261/142, 128/186-196, 128/DIG. 2, 219/271-275, 219/362, 137/558, 55/164, 55/227, 55/244-248, 55/257, 55/274
• US Class Current: 261/122.1
• CPC Class Codes: A61M 16/1075 by influencing the temperature A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/109 the humidifying liquid or the beneficial agent
• CPC Class Codes: A61M 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/167 acting vertically on the valve
• CPC Class Codes: A61M 2205/3386 Low level detectors
• CPC Class Codes: Y10S 261/65 Vaporizers
• CPC Class Codes: Y10T 137/8342 Liquid level responsive indicator, recorder or alarm

Abstract

A humidifier system for delivering breathing gases such as air or oxygen from a respirator, anesthesia machine, oxygen source, or the like to a patient under controlled conditions of temperature and humidity is disclosed. The humidifier comprises a support housing adapted to receive a removable water tank, the housing also containing a low water sensing system, a water heating means, and a system for sensing and for regulating the temperature of the water in the tank. The tank includes an air inlet leading to a diffuser chamber, from which air flows through a diffuser plate, through the water to the humidifier, and thence to an outlet for delivery to the patient. The diffuser plate incorporates a plurality of cone-shaped apertures which create air turbulence in the water so that as the breathing gases are forced through the water tank under positive pressure, the gases are uniformly heated and humidified prior to delivery.

Claims

1. An improved system for humidifying breathing gases, comprising:

a support housing defining a recess;

heater means in said recess and carried by said support housing;

container means for holding a supply of water, said container means including gas inlet and gas outlet means;

means removably securing said container means in said recess in heat transfer relationship with said heater means;

diffuser means within said container and spaced therefrom to define a diffuser chamber, said chamber being so located as to be below the surface of the supply of water during operation of said system and so located as to permit a free flow of water therearound, said diffuser means including a diffuser plate defining the upper surface of said diffuser chamber and including a multiplicity of apertures, each said aperture having the shape of a truncated cone with its smallest diameter being at the upper surface of said diffuser plate and its largest diameter being at the lower surface of said diffuser plate, said apertures passing said breathing gas upwardly out of said diffuser chamber through said diffuser plate and into the water thereabove in the form of minute bubbles;

means including said gas inlet means communicating with said diffuser chamber for directing said breathing gas into said diffuser chamber below the surface of the supply of water, said breathing gas thereafter passing upwardly through said diffuser plate and the supply of water;

means including said gas outlet means communicating with the interior of said container to direct said breathing gas out of said container; and

a contaminant trap connected to said gas outlet means and located within said container receiving and retaining backflowing contaminated liquid which returns from said outlet means to said container.

2. The system of claim 1, wherein the smallest diameter of each said aperture is sufficiently large to allow breathing gas to flow through said diffuser plate at positive gas inlet pressures, and is sufficiently small to prevent gas flow in the absence of positive gas inlet pressures.

3. The system of claim 2, wherein the smallest diameter of each said aperture is between about 0.050 and about 0.056 inch.

4. The system of claim 3, wherein the largest diameter of each said aperture is between about 2 and about 3 times as large as the smallest diameter thereof.

5. An improved system for humidifying a breathing gas, comprising:

container means adapted to receive a supply of water through which a breathing gas is passed for humidification, said container having bottom, wall and cover portions;

diffuser means mounted within said container and so located as to be below the surface of the water during operation of said system, said diffuser means including a diffuser plate defining the top wall of a diffuser chamber adjacent but smaller than the bottom portion of said container, said diffuser plate having a multiplicity of small conical apertures for passing breathing gas out of said chamber, and said diffuser chamber having side edges spaced from the wall portion of said container to permit free circulation of water around the diffuser chamber;

gas inlet means extending into said container and communicating with said diffuser chamber to direct breathing gas into said diffuser chamber, said breathing gas flowing from said diffuser chamber upwardly through said conical diffuser plate apertures whereby the gas is formed into streams of small bubbles for passage through the water into the container;

gas outlet means communicating with the interior of said container, said outlet means being located between a side edge of said diffuser and the wall portion of the container and above the surface of the water during operation of the system for collecting humidified breathing gas that has passed through the water;

baffle wall means located between said diffuser plate and said outlet means preventing bubble turbulent water from entering said outlet means while permitting humidified gas to flow thereto; and

a contaminant trap connected to said gas outlet means and located within said container receiving and retaining backflowing contaminated liquid which returns from said outlet means to said container.