Abstract: A variable-ratio angular speed converter of the gear box type is arranged so that each speed reduction setting on the output shaft is a prescribed fraction of the speed reduction of the next-preceding setting. A first tapered gear cluster is fixedly supported on the input shaft, while a plurality of similar second clusters are supported in spaced relation for rotation on an intermediate shaft. Successive speed reductions of the same nominal ratio are imparted (1) between the first cluster on the input shaft and the first second cluster on the intermediate shaft and (2) between successive second clusters on the intermediate shaft. A housing adjustably supported on the output shaft has a selector gear for engaging an arbitrary one of the gears on any of the first and second clusters.

Abstract: A pneumatic regulator including a constant-volume reference chamber and associated pressure-sensitive inflation and deflation valves is provided to effect a precise linear depressurization of a variable-volume inflatable enclosure, such as a cuff which has been applied to a patient during a blood pressure measurement thereof and pressurized to a value higher than the patient's systolic pressure. By coupling such regulator to the drive for one axis of an X-Y recording chart, the pen or marker of the chart can be precisely scanned along the associated chart axis at the constant depressurization rate of the cuff.

Abstract: An infusion pump suitable, e.g., for delivering an adjustable, metered amount of a drug to a patient includes a pre-sterilized, thin-walled plastic syringe which is employed solely as a sterile inner liner for an outer, thick-walled split cylindrical clamp that is axially coextensive with the plastic syringe barrel. The required effect is obtained by inwardly squeezing the clamp against the wall of the plastic syringe until the two parts of the clamp come together to define a bore of a standard inner diameter. A plunger, which is tightly engaged with the wall of the so-deformed plastic syringe to prevent leakage of the drug, is normally driven at one of a plurality of selectable speeds by means of a gear box that is specially constructed to vary the plunger speed travel, and thereby the fluid flow rate of the drug in the syringe, in successive steps with each step being a predetermined constant fraction of the next-preceeding step.

Abstract: A method of detecting and recording a succession of time-spaced blood flow surges utilizing a pneumatic regulator including a constant-volume reference chamber and associated pressure-sensitive inflation and deflation valves is provided to effect a precise linear depressurization of an inflatable cuff which has been applied to a patient and pressurized to a value higher than the patient's systolic pressure. Pulses obtained from an ultrasonic or other suitable detector sensitive to movements of the patient's arterial wall in synchronism with the blood flow surges as the cuff is depressurized below the patient's systolic pressure are integrated and then translated into variable-duration marking impulses. Such impulses are successively applied to the actuating input of a pen or other marker associated with an X-Y recording chart, the pen being linearly scanned along one chart axis at the constant depressurization rate of the cuff.

Abstract: An alarm actuating circuit associated with an automatic blood pressure recorder is triggered when a patient's systolic or diastolic pressure does not fall within a prescribed range. The recorder is associated with a pneumatic regulator including a constant-volume reference chamber and associated pressure-sensitive inflation and deflation valves to effect a precise linear depressurization of an inflatable cuff which has been applied to the patient and pressurized to a value higher than the patient's systolic pressure. Pulses obtained from an ultrasonic or other suitable detector sensitive to movements of the patient's arterial wall in synchronism with the blood flow surges as the cuff is depressurized below the patient's systolic pressure are integrated and then translated into variable-duration marking impulses.

Abstract: A pneumatic regulator including a constant-volume reference chamber and associated pressure-sensitive inflation and deflation valves is provided to effect a precise linear depressurization of an inflatable cuff which has been applied to a patient and pressurized to a value higher than the patient's systolic pressure. Pulses obtained from an ultrasonic or other suitable detector sensitive to movements of the patient's arterial wall in synchronism with the blood flow surges as the cuff is depressurized below the patient's systolic pressure are integrated and then translated into variable-duration marking impulses. Such impulses are successively applied to the actuating input of a pen or other marker associated with an X-Y recording chart, the pen being linearly scanned along one chart axis at the constant depressurization rate of the cuff.