Variable aerosol heater with automatic temperature control

Claim 2

In combination with an inhalation therapy device of the type wherein a column of water is drawn from a receptacle through an electric heating unit, whereby the water is heated, and into an atomizing device, whereby the heated water is atomized, and wherein the heated water is combined with a flow of oxygen to provide a stream of humidified oxygen and wherein said stream of humidified oxygen is delivered through an extended hose to the site of a patient, and wherein the stream of humidified oxygen is thereat administered to said patient, the improvement which comprises: means for sensing the temperature of the stream of humidified oxygen at the said patient site immediately prior to its administration to the said patient and for generating an electrical signal representative of said temperature; and, control means responsive To said signal for controlling the amount of heat generated by said electric heating unit to maintain the stream at a preselected temperature; wherein said control means comprises: gate controlled bilateral switch means for controlling the flow of electric current through said electric heating unit; means for amplifying said electrical signal; and, means connected to the gate electrode of said bilateral switch means for controlling the conductive state of said swtich means in response to said amplified electrical signal; means for sensing the temperature of said electric heating unit and generating an output signal indicative thereof; and, means for overriding said amplified electrical signal and causing said bilateral switch means to be in its non-conductive state when said output signal indicates a preselected maximum temperature.

Claim 3

In combination with an inhalation therapy device of the type wherein a column of water is drawn from a receptacle through an electric heating unit, whereby the water is heated, and into an atomizing device, whereby the heated water is atomized, and wherein the heated atomized water is combined with a flow of oxygen to provide a stream of humidified oxygen which is administered to a patient, the improvement which comprises: means for sensing the temperature of the stream of humidified oxygen immediately prior to its administration to the patient and for generating an electrical signal representative of said temperature; and, control means responsive to said signal for controlling the amount of heat generated by said electric heating unit to maintain the stream at a preselected temperature, said control means comprising: gate controlled bilateral switch means for controlling the flow of electric current through said electric heating unit; means for amplifying said electrical signal; means connected to the gate electrode of said bilateral switch means for controlling the conductive state of said swtich means in response to said amplified electrical signal; means for sensing the temperature of said electric heating unit and generating an output signal indicative thereof; means for overriding said amplified electrical signal and causing said bilateral switch means to be in its non-conductive state when said output signal indicates a preselected maximum temperature; and, circuit means for temporarily modifying the operation of said overriding means such that the bilateral switch means is not caused to become non-conductive until said output signal indicates another preselected maximum temperature which is higher than said first-mentioned preselected maximum temperature.

Claim 4

In combination with an inhalation therapy device of the type wherein a column of water is drawn from a receptacle through an electric heating unit, whereby the water is heated, and into an atomizing device, whereby the heated water is atomized, and wherein the heated atomized water is combined with a flow of oxygen to provide a stream of humidified oxygen which is administered to a patient, the improvement which comprises: means for sensing the temperature of the stream of humidified oxygen immediately prior to its administration to the patient and for generating an electrical signal representative of said temperature; and, control means responsive to said signal for controlling the amount of heat generated by said electric heating unit to maintain the stream at a preselected temperature, said control means comprising: gate controlled bilateral switch means for controlling the flow of electric current through said electric heating unit; means for amplifying said electrical signal; means connected to the gate electrode of said bilateral switch means for controlling the conductive state of said swtich means in response to said amplified electrical signal; means for sensing the temperature of said electric heating unit and generating an output signal indicative thereof; means for overriding said amplified electrical signal and causing said bilateral switch means to be in its non-conductive state when said output signal indicates a preselected maximum temperature; and, circuit means for temporarily modifying the operation of said overriding means such that the bilateral switch means is not caused to become non-conductive until said output signal indicates another preselected maximum temperature which is higher than said first-mentioned preselected maximum temperature.

Claim 5

The combination of claim 2, wherein said control means includes means for visually indicating if the device is properly grounded.

Claim 6

The combination of claim 3, wherein said ground indicating means includes: an indicator lamp; an amplifier in series with said lamp; circuit means for biasing said amplifier into conduction when the device is connected to ground; a photo-tranistor connected to said amplifier so as to cause said amplifier to become non-conductive when said photo-transistor is conductive; a light emitting diode optically coupled to said photo-transistor; and, switch means responsive to the activation of said circuit operation modifying means for energizing said light emitting diode only when said circuit operation modifying means is energized.

Claim 7

In combination with an inhalation therapy device of the type wherein a column of water is drawn from a receptacle through an electric heating unit, whereby the water is heated, and into an atomizing device, whereby the heated water is atomized, and wherein the heated atomized water is combined with a flow of oxygen to provide a stream of humidified oxygen which is administered to a patient, the improvement which comprises: means for sensing the temperature of the stream of humidified oxygen Immediately prior to its administration to the patient and for generating an electrical signal representative of said temperature; and, control means responsive to said signal for controlling the amount of heat generated by said electrical heating unit to maintain the stream at a preselected temperature, said control means comprising: gate controlled bilateral switch means for controlling the flow of electric current thorugh said electric heating unit; means for amplifying said electrical signal; and, means connected to the gate electrode of said bilateral switch means for controlling the conductive state of said switch means in response to said amplified electrical signal, said means for controlling the conductive state of said gate controlled bilateral switch means comprising: capacitor means for providing triggering current to the gate electrode of said bilateral switch means; a diode bridge rectifier circuit having one input lead connected to said capacitor means so that said capacitor means is charged by the rectifier current; a photo-transistor connected in series with said bridge rectifier output; and a light emitting diode optically coupled to said photo-transistor for controlling the conductive state of said photo-tranistor in response to said amplified electrical signal.

Claim 8

In combination with an inhalation therapy device of the type wherein a column of water is drawn from a receptacle through an electric heating unit, whereby the water is heated, and into an atomizing device, whereby the heated water is atomized, and wherein the heated atomized water is combined with a flow of oxygen to provide a stream of humidified oxygen which is administered to a patient, the improvement which comprises: means for sensing the temperature of the stream of humidified oxygen Immediately prior to its administration to the patient and for generating an electrical signal representative of said temperature; and, control means responsive to said signal for controlling the amount of heat generated by said electrical heating unit to maintain the stream at a preselected temperature, said control means comprising: gate controlled bilateral switch means for controlling the flow of electric current thorugh said electric heating unit; means for amplifying said electrical signal; and, means connected to the gate electrode of said bilateral switch means for controlling the conductive state of said switch means in response to said amplified electrical signal, said means for controlling the conductive state of said gate controlled bilateral switch means comprising: capacitor means for providing triggering current to the gate electrode of said bilateral switch means; a diode bridge rectifier circuit having one input lead connected to said capacitor means so that said capacitor means is charged by the rectifier current; a photo-transistor connected in series with said bridge rectifier output; and a light emitting diode optically coupled to said photo-transistor for controlling the conductive state of said photo-tranistor in response to said amplified electrical signal.