Abstract: A frequency modulated control circuit for an electronic fuel injection system to control the pulse-type injection of fuel at a single point of the fuel intake of an internal combustion engine in accordance with the derived mass air flow rate into the engine comprising a pressure sensor for sensing the manifold pressure of the internal combustion engine, and an engine speed sensor, both of which generate an analog signal which are multiplied by a multiplier circuit to provide a signal representative of the mass air flow to the engine. The multiplier circuit includes a separate control input for varying the output signal level of the multiplier circuit by a preselected factor determined by the final output of the control circuit. The output of the multiplier circuit is fed to a voltage controlled oscillator to produce an output signal taking the form of a pulse train, the frequency of which varies with the amplitude of the mass air flow signal.

Abstract: A skid control system for use in connection with controlling the application of the brakes on a two-wheeled vehicle which includes a sensor device for sensing the velocity of wheel rotation, a triple integration circuit connected to the sensor for producing an analog signal which is proportional to the wheel velocity and a proportioning circuit connected to the triple integration circuit. The output of the proportioning circuit is fed to a hysteresis and low speed cut-off circuit, and a ramp generator circuit, the outputs of the two above noted circuits being fed to the input of a comparator circuit which compares the wheel velocity with a simulated vehicle velocity signal generated by the ramp generator circuit. The output of the comparator is utilized to control a brake application valve associated with the brake system.

Abstract: A system for measuring the duration of the Achilles tendon reflex after the tendon has been tapped by a percussion hammer, the system including an input transducer which converts the reflex extension of the ankle joint to an electric signal which is fed to the input of an amplifier, the output of the amplifier being fed to a peak holder and to a comparator circuit. A portion of the signal from the peak holder is also fed to the comparator circuit which detects a crossover point of the two signals fed to the comparator. The first such crossover occurs during the hammer tap "artefact" and the second such crossover occurs during the relaxation phase of the reflex action. A timing device (such as an integrator) measures the time elapsed between the two crossovers and displays the result.

Abstract: A vortex type flowmeter having a body member, a cover member and an interior varying diameter cavity formed in the body member in which fluid is introduced to flow in a generally helical pattern within the cavity, the fluid being introduced at the periphery of the cavity having the largest diameter and the fluid exiting from an aperture at the center of the vortex formed by the helical flow. The flowmeter includes a toothed rotor mounted for rotation within the cavity and the flow of fluid causes the rotor to rotate within the cavity at a rotational rate which is generally directly related to the velocity of flow. The flowmeter is provided with a light-emitting diode and photosensitive transistor combination which senses the passage of each of the teeth as the rotor is rotating within the cavity.

Abstract: A control circuit for a double acting electromagnet has two capacitors connecting opposite ends of the electromagnet to one supply line. The ends of the electromagnet can also be connected to the other supply line by way of a two position contact and a normally open switch. The capacitors control energisation of the electromagnet.