Technique and apparatus for measuring and monitoring the mechanical impedance of body tissues and organ systems

Claim 5

Apparatus for the measurement of the resistance and reactance of the lungs comprising: an air driver unit producing an oscillating source of air in response to energization thereof, an oscillator energizing said air driver unit at a frequency within the range of 5 to 50 cycles per second, a breathing appliance pneumatically coupled to said air driver unit, said air driver unit being mechanically tuned to the frequency of said oscillator so that the motion of the air in the breathing appliance is in phase with the force applied by said air driver when the breathing appliance is occluded and when the breathing appliance is open, a first transducer for producing a first electrical signal representing the force applied to the air in said breathing appliance, a second transducer producing a second electrical signal representing the actual motion of the air in said breathing appliance, measuring circuitry responsive to said first and second electrical signals for producing an output representing the amplitude of said movement relative to said force, and measuring circuitry responsive to saiD first and second electrical signals for producing an output representative of the phase difference between said first and second electrical signals, said outputs together providing an impedance profile of the lungs.

Claim 6

Apparatus for the measurement of the resistance and reactance of the lungs comprising: an air driver unit producing an oscillating source of air in response to energization thereof, an oscillator energizing said air driver unit at a frequency within the range of 5 to 50 cycles per second, a breathing appliance pneumatically coupled to said air driver unit, said air driver unit being mechanically tuned to the frequency of said oscillator so that the motion of the air in the breathing appliance is in phase with the force applied by said air driver when the breathing appliance is occluded and when the breathing appliance is open, a first transducer for producing a first electrical signal representing the force applied to the air in said breathing appliance, a second transducer producing a second electrical signal representing the actual motion of the air in said breathing appliance, measuring circuitry responsive to said first and second electrical signals for producing an output representing the amplitude of said movement relative to said force, and measuring circuitry responsive to saiD first and second electrical signals for producing an output representative of the phase difference between said first and second electrical signals, said outputs together providing an impedance profile of the lungs.

Claim 7

The apparatus recited in claim 3 further comprising: a side tube pneumatically coupling said air driver and said breathing appliance to the atmosphere so that normal breathing can be accomplished through said breathing appliance.

Claim 8

Apparatus for the measurement of the resistance and reactance of the lungs comprising: an air driver including a diaphragm, a first coil for driving said diaphragm in an oscillating motion in response to an electrical signal applied thereto, an oscillator for driving said first coil at a frequency within the range of 5 to 50 cycles per second, a breathing appliance pneumatically coupled to a chamber on one side of said diaphragm, a second coil mounted on said diaphragm and producing an electrical signal representing the actual motion of said diaphragm, a phase detector for comparing the signal applied to said first coil with the signal appearing on said second coil to determine the relative phase between said two signals, and an amplitude detector, said signal representing the actual motion of said diaphragm being applied to said amplitude detector to produce an output representing the magnitude of the impedance of the lungs.

Claim 9

Apparatus for the measurement of the resistance and reactance of the lungs comprising: an air driver including a diaphragm, a first coil for driving said diaphragm in an oscillating motion in response to an electrical signal applied thereto, an oscillator for driving said first coil at a frequency within the range of 5 to 50 cycles per second, a breathing appliance pneumatically coupled to a chamber on one side of said diaphragm, a second coil mounted on said diaphragm and producing an electrical signal representing the actual motion of said diaphragm, a phase detector for comparing the signal applied to said first coil with the signal appearing on said second coil to determine the relative phase between said two signals, and an amplitude detector, said signal representing the actual motion of said diaphragm being applied to said amplitude detector to produce an output representing the magnitude of the impedance of the lungs.

Claim 10

The apparatus recited in claim 5 further comprising a recorder for displaying the output of said phase detector relative to the output of said amplitude detector to display the total impedance profile of the lungs.

Claim 11

The apparatus recited in claim 5 wherein said air driver includes an enclosure, said diaphragm being mounted in said enclosure to divide it into two chambers, said breathing appliance being pneumatically coupled to one of said chambers, said air driver being mechanically tuned to the given frequency of said oscillator so that the motion of the diaphragm is in phase with the signal from said oscillator when the breathing appliance is occluded and when the breathing appliance is opened.

Claim 12

Apparatus for the measurement of the resistance and reactance of the lungs comprising: an air driver including a diaphragm, a first coil for driving said diaphragm in an oscillating motion in response to an electrical signal applied thereto, an oscillator for driving said first coil at a frequency within the range of 5 to 50 cycles per second, a breathing appliance pneumatically coupled to a chamber on one side of said diaphragm, a second coil mounted on said diaphragm and producing an electrical signal representing the actual motion of said diaphragm, a resistance detector for determining the magnitude of that portion of the electrical signal produced by said second coil which is in phase with the electrical signal applied to said first coil, and a reactance detector for determining the magnitude and polarity of that portion of the electrical signal produced by said second coil which is 90* out of phase with the electrical signal applied to said first coil.

Claim 13

Apparatus for the measurement of the resistance and reactance of the lungs comprising: an air driver including a diaphragm, a first coil for driving said diaphragm in an oscillating motion in response to an electrical signal applied thereto, an oscillator for driving said first coil at a frequency within the range of 5 to 50 cycles per second, a breathing appliance pneumatically coupled to a chamber on one side of said diaphragm, a second coil mounted on said diaphragm and producing an electrical signal representing the actual motion of said diaphragm, a resistance detector for determining the magnitude of that portion of the electrical signal produced by said second coil which is in phase with the electrical signal applied to said first coil, and a reactance detector for determining the magnitude and polarity of that portion of the electrical signal produced by said second coil which is 90* out of phase with the electrical signal applied to said first coil.

Claim 14

The apparatus recited in claim 8 further comprising a recorder for displaying the output of said resistance detector relative to the output of said reactance detector to display the total impedance profile of the lungs.