SYSTEM FOR MEASURING TIMED FORCED EXPIRATORY VOLUME

摘要

The system generates a signal representative of instantaneous forced expiratory volume for three successive tests. The signal is fed to a multi-channel analog memory. Each channel includes a peak detector circuit and a meter or other recording or measuring means. One channel measures and records the largest value of total forced expiratory volume for the three tests; and the other channels measure and record the largest value of forced expiratory volumes at predetermined time increments for the three tests. Circuitry is included for directly computing the timed forced expiratory volumes as percentages of the total forced expiratory volume. The three tests are also recorded on a graph. Another memory channel may be included for storing a signal representative of the maximum flow rate for the tests. The memory channels are all reset in common after the completion of the tests.