| 摘要 |
1,215,904. Monitoring breathing. O. VIERLING. 30 May, 1968 [20 July, 1968], No. 27497/69. Heading A5K. [Also in Division G1] In a device for supervising and indicating breathing, a probe 1 is inserted into the nose, and variations in air flow during breathing are converted into a sinousoidal voltage appearing at the tapping point of two N.T.C. resistors 4, 5 mounted in a measuring chamber 2. This signal is amplified at 6, rectified at 8, and during breathing a capacitor 11 is charged, capacitor 11 being discharged during the pause between breathing. If the voltage on capacitor 11 falls below a threshold value set by circuit 13, e.g. a Schmitt trigger, this circuit 13 activates a generator 14 connected to a loudspeaker 15 and a relay 16 which closes its switch 17 to actuate further alarm systems. Both the intensity and frequency of breathing may be indicated on meters 9 and 7 respectively and may be recorded. Resistor 10 is adjustable to set the discharge rate of capacitor 11 and thus the permissible pause between breaths before the alarm is actuated. The amplifier is adjustible for the intensity of breathing. |
