Abstract: A fuel control system for an internal combustion engine with correction for optimum values based on a variety of factors. Characteristic engine data is stored in preferably digital memories with capabilities for interpolation. Upon addressing the engine data fields with input signals related to current operational variables, for example the accelerator pedal position, the control system derives therefrom a nominal air flow rate which is used as the reference value in a control loop that sets the amount of recycled exhaust gas and the fresh air flow. As the actual air flow rate approaches the reference value, the fuel flow is adjusted to insure correct mixtures at all times. In another embodiment, the fuel is supplied on demand but cannot exceed a maximum value except under special override conditions. Several other embodiments and variants are presented.

Abstract: Armature reaction in a dynamo is reduced by constructing the main pole structure and/or the commutating pole structure with a plurality of iron lamina arranged parallel to the axis of rotation of the dynamo. The iron lamina are separated from each other by nonmagnetic or magnetically weak material of a predetermined thickness designed to cause a predetermined minimum but high reluctance to be offered to flux generated in the main or commutating pole structure as a result of armature current. The core of each pole may be split into a first and second core half at the root and in the direction of the axis of rotation. Each core half has a larger portion which extends to the adjacent core half of the neighboring pole, thereby forming a yoke. A smaller portion of each core half extends into the air gap between poles and, together with the corresponding portion of the core half of the neighboring pole which is similarly extended into the same air gap, forms a commutating pole.

Abstract: For use in association with a fuel mixture preparation system of an internal combustion engine which uses closed-loop control based on exhaust chemistry as determined by an oxygen sensor, there is described a circuit which monitors the operational readiness of the oxygen sensor on the basis of its internal resistance. The measurement takes place in a bridge circuit which is supplied with current whenever the sensor is non-operative but which becomes inactive when the sensor is at normal temperatures. The bridge voltages are fed to a comparator which generates an average output value when the oxygen sensor is not yet ready for operation and this average signal is processed in an integrator for final control of the fuel-air mixture.

Abstract: A cyclical ON-OFF control signal is generated with a predetermined duty cycle to energize a load through a semi-conductor switch; a trouble signal is generated, for example by sensing voltage across the load, across the switch, temperature or the like, and, when the trouble signal exceeds a certain threshold (as determined, for example, by comparing the trouble signal with a reference in a differentially connected operational amplifier), the ON-signal to gate the switch ON is interrupted; and an OFF cycle of the cyclical generating means is started; if the trouble signal disappears, the normal cyclical repetition rate continues. A minimum interruption time is, however, provided determined by the OFF period of the cyclical generator and/or circuit components.