Abstract: A method of manufacturing a diaper includes constructing a backing sheet having an exterior surface and an interior surface so a to form an exterior of the diaper and an interior of the diaper, bonding a tissue layer to the interior surface of the backing sheet, bonding an elastic pouch to the exterior surface of the backing sheet to contain a detector module, and placing sensing electrodes within the interior of the diaper along the interior surface of the backing sheet in contact with the tissue layer that is bonded to the backing sheet, and in a direction to extend opposite the elastic pouch that is bonded to the outside of the backing sheet so as to allow the sensing electrodes to couple capacitively to the sensor module.

Abstract: A pair of spaced electrodes within an area subject to wetness couple non-conductively with a sensor protected from wetness, and an alarm sounds in response to moisture decreasing the resistance between the electrodes. For example the electrodes project into the absorbent material of a diaper and extend along the inside of the diaper sheath opposite a pouch on the outside of the sheath. The pouch contains a sensor capacitively coupled to the electrodes.

Abstract: The apparatus disclosed herein utilizes ultrasound to characterize the flow of fluid material containing suspended particles. Energy scattered by particles in the moving fluid from a brief emitted burst is detected to obtain a return signal and this return signal is compared with a preselected amplitude at a preselected time interval after each burst. Preferably the amplitude threshold is an integrated or filtered value corresponding to the amplitude of the return signal over some earlier time. A binary output signal is generated which continues from each comparison to the next at a level corresponding to the result of the comparison. Accordingly, the output signal includes frequency components representative of Doppler shifts occasioned by the movement of fluid.