Abstract: A blood flow monitoring system employing a disposable sensor for directing a flow of blood through an electromagnetic field to generate a voltage proportional to the flow of blood through the electromagnetic field. The flow detection system employs a disposable sensor having a lumen with a constricted cross-sectional area adapted to interact with an electromagnetic field to detect blood flow and in an enhanced variation includes an electromagnetic field focusing device for enhancing the electromagnetic field to focus the electromagnetic field across the path of blood flow through the constricted section of the lumen to intensify the voltage generated by the blood flow through the intensified electromagnetic field.

Abstract: Apparatus is disclosed for actuating hydraulic motor control valves in a predetermined timed relationship relative to a pump inlet valve, wherein the pump is connected to and driven by the hydraulic motor, to improve the metering capabilities of the motor-pump combination.

Abstract: An apparatus and method for a fluid metering system that employs a high resolution position sensor and electronics to very accurately control the amount of fluid dispensed. This sensor may be an optical sensor which translates the movement of a positive displacement pump into electrical signal pulses that are serially fed into a counter which converts them to parallel binary or binary-coded decimal form. The optical sensor uses a light-sensitive transducer to convert light rays to electrical pulses, a light source, and two graticule frames therebetween. One graticule frame moves relative to the other graticule. Each of the graticules has a large number of equally-spaced light-transmitting areas. Preset counts in the counter compensate for time lags in the system operation such as the lag due to the movement of the dispensing valve and the solenoid valve in an actuating piston.