US 4,621,632 A · Humidifier system

Abstract

A humidifier system including a humidifier chamber and heater assembly, microprocessor based control circuitry, and a housing for the control circuitry. The humidifier system is adapted to provide air at nearly 100 percent relative humidity and at a predetermined temperature (e.g. 35.degree. C.) to a medical (e.g. critical care) patient. The humidifier chamber includes a continuous spiral heat exchange path which extends between a vapor storage chamber and an outlet of the humidifier chamber at which an air heating tube is connected, so that outgoing air can be delivered to the patient. The vapor storage chamber is interfaced with a ventilator source of incoming air and a relatively small reservoir in which a supply of water is boiled by the heater assembly for providing vapor saturated air from the vapor storage chamber to the heat exchange path. The control circuitry includes a pair of sensors which are responsive to the temperature of the outgoing humidified air at the humidifier chamber outlet and at the patient end of the heating tube. The temperatures sensed are used to control the energization of both the heater assembly and a heating element of the heating tube, so that humidified air can be delivered to the patient at the predetermined temperature and with minimal condensate rainout.

Claims23

Dependent claims

A humidifier system for heating and humidifying breathable gas supplied to a patient by a medical ventilator or other source of such gas, said system comprising:

a chamber having a gas inlet adapted to receive breathable gas from a source thereof, a gas outlet for delivering the gas to the patient, and a reservoir;
water intake means for periodically supplying a relatively small amount of water to said reservoir from a source thereof;
water heater means, associated with said reservoir, for boiling the water in said reservoir to generate steam;
vapor storage means in said chamber and communicating with said gas inlet and with said reservoir, for introducing the incoming gas from said inlet to the steam generated by said heater means, thereby heating said gas and saturating said gas with water vapor from said steam;
and
heat exchanger means, disposed between said vapor storage means and said gas outlet, for condensing vapor from the heated, vapor-saturated gas flowing from said vapor storage means, whereby heated gas at approximately 100 percent relative humidity is provided to said gas outlet for delivery to the patient.

3 more elements

A humidifier system, comprising:

a chamber having a gas inlet for receiving breathable gas from a source thereof, a gas outlet, and a water reservoir;
water intake means for periodically supplying a relatively small amount of water to said reservoir from a water source;
a tube having a first end connected to said gas outlet, a second end adapted to be coupled to the respiratory system of a patient, and a heating element disposed between said first and second ends;
water heater means in said chamber, and operably associated with said reservoir, for boiling the water in said reservoir, thereby generating steam which heats and vapor-saturates the gas flowing into said chamber through said gas inlet;
heat exchanger means in said chamber for (a) receiving the heated, vapor-saturated air, and (b) cooling the vapor-saturated gas to cause the condensation of vapor therefrom as said gas travels to said outlet, whereby the gas at said outlet has a relative humidity of approximately 100 percent and a lower temperature than when said gas is received by said heat exchanger means;
first temperature-sensing means for sensing the gas temperature at or near the second end of said tube;
second temperature-sensing means for sensing the gas temperature at or near said gas outlet;
and
servo control means for controlling the heat generated by said heating element and said water heater means in response to the temperatures sensed by said first and second temperature-sensing means.

6 more elements

A humidifer system for heating and humidifying breathable gas supplied to a patient by a medical ventilator, said system comprising:

a chamber having a gas inlet adapted to be coupled to said ventilator, a gas outlet, and a water reservoir;
water intake means for periodically supplying a relatively small amount of water to said reservoir from a water source;
steam-generating means, operatively associated with said reservoir, for (a) boiling the water in said reservoir to produce steam, and (b) introducing the air flowing through said gas inlet to said steam, thereby heating and vapor-saturating said gas;
heat exchanger means in said chamber configured to form a gas flow path between said steam-generating means and said gas outlet, for condensing water vapor from the heated, vapor-saturated gas received from said steam-generating means, whereby the gas at said outlet has a relative humidity of approximately 100 percent at a lower temperature than when said gas is recieved by said heat exchanger means;
a gas delivery tube having a first end coupled to said gas outlet and a second end adapted to be coupled to said patient;
temperature-sensing means for providing a temperature-indicative signal in response to the gas temperature at or near the second end of said gas delivery tube;
and
servo control means for controlling the energization of said steam-generating means in response to the value of said temperature-indicative signal.

5 more elements

Dependencies are inferred from the claim text.

Humidifier system

Life of this patent

Humidifier system

Life of this patent

Abstract

Claims23