Abstract: An open circuit gravity-assisted uroflowmeter has a urine collector having a generally open inlet in fluid communication with a sensing passage located at a lower elevation than the inlet, the sensing passage intersecting a magnetic field and having electrodes for detecting a flow-dependent voltage induced by the passage of urine through the magnetic field. Preferred embodiments of the uroflowmeter may have low pressure drop, rapid response and simple construction.

Abstract: A passive flowmeter having an inlet, sensing passage and outlet in fluid communication with one another, the sensing passage having a noncircular cross-section having a minor axis generally aligned with a permanent magnetic field and a major axis generally aligned with at least a pair of generally opposed electrodes for detecting a flow-dependent voltage induced by the passage of conductive liquid through the magnetic field. By using both permanent magnets and a noncircular cross-section sensing passage together in the same device, much greater latitude in magnet selection may be obtained. This may facilitate for example the use of lower cost permanent magnets and the construction of a lower cost device for disposable flowmeter applications.

Abstract: An integral trap magnetic flowmeter having an inlet in fluid communication with a sensing passage, the sensing passage intersecting a magnetic field, having electrodes for detecting a flow-dependent voltage induced by the passage of conductive liquid through the magnetic field, and having an outlet at an elevation such that the sensing passage volume normally remains filled with conductive liquid. By maintaining standing liquid in the sensing passage at a height sufficient to fill the sensing passage volume, the flowmeter's response may be made more rapid and more accurate, particularly during the early stages of a short duration liquid discharge. By providing an integral trap, installation errors may be reduced.