초록 ▼

Sensitivity or span calibration is adjusted to a desired value by (1) noting the display indication with the reference side of the transducer at atmospheric pressure, (2) substituting a known offset pressure for atmospheric pressure on the reference side, to produce a new display indication, and (3)

Sensitivity or span calibration is adjusted to a desired value by (1) noting the display indication with the reference side of the transducer at atmospheric pressure, (2) substituting a known offset pressure for atmospheric pressure on the reference side, to produce a new display indication, and (3) adjusting the display to produce that amount of displacement (between the display indications in steps 1 and 2) which corresponds to the known offset pressure multiplied by the desired calibration value. With the sensitivity or span calibration adjusted to a desired value, the zero point of the display is adjusted by (1) independently measuring the mean of the actual pressure, (2) noting the mean value of the display indication, and (3) adjusting the zero point to eliminate discrepancy between the mean value of the display and the mean of the actual pressure. The apparatus has a port for a substitute reference pressure, and an external pressure gauge for measuring the mean pressure through an auxiliary lumen of the catheter.

대표청구항 ▼

A method for first calibrating then zeroing a catherer-tip gauge-pressure transducer system having a pressure-sensitive diaphragm with a measurement side exposed to a pressure to be measured and a reference side normally exposed to atmospheric pressure, and haivng a display apparatus responsive to t

A method for first calibrating then zeroing a catherer-tip gauge-pressure transducer system having a pressure-sensitive diaphragm with a measurement side exposed to a pressure to be measured and a reference side normally exposed to atmospheric pressure, and haivng a display apparatus responsive to the diamphragm to provide an indication upon a calibratable scale of the pressure to be measured relative to atmospheric pressure said method comprising the steps of: (a) noting the pressure indicated by the display apparatus while the measurement side of the diaphragm is exposed to a pressure to be measured and the reference side of the diaphragm is exposed to atmospheric pressure; then (b) substituting a known pressure for atmospheric pressure at the reference side of the diaphragm to produce a new pressure indication; then (c) using the noted pressure indication of step (a), the known pressure of step (b), and the new pressure indication of step (b) calibrating the display apparatus scale in accordance with a calibration factor; then (d) while establishing a constant reference pressure at the measurement side of the diaphragm, determining a mean value of the calibrated display-apparatus indication plus independently measuring a pressure substantially at the location of the reference side of the diaphragm; then (e) calculating the difference between the independently measured pressure of step (d) and the calibrated display-apparatus indication of step (d); then (f) adjusting the zero of the display apparatus in such a way as to cancel the difference calculated in step (e); therein the display apparatus is calibrated, and is also zeroed for operation while the constant reference pressure is at the measurement side of the diaphragm.