摘要:
In order to control the spark advance of an internal combustion engine in the idling domain, the invention provides circuitry for increasing the spark advance below an upper rpm limit and returning the ignition timing to normal when the engine speed drops below a second lower limit. The continuous temporal shift of an output signal which may be used for engaging the ignition control system of the engine is provided by a very small number of elements, in particular only two timing elements, a flip-flop and a number of logical gates. The two flip-flops are triggered by the respective leading and trailing edges of the engine speed transducer signal. One of the flip-flops defines the upper engine speed limit while the second timing element defines the lower engine speed limit. Two embodiments of the invention are described.
摘要:
A power unit (79) includes a spark advance unit (80) connected to a solid state ignition system (81) for selectively supplying ignition sparks to operate an internal combustion engine (83). A pulse generator (107) responds to a series of negative polarity half-cycle alternations (96) provided by an alternator winding (20') to provide a first pulse output (110) of a first frequency. A pulse counter (119) counts the pulses of the first pulse output (110) to provide a second pulse output (120) having a second frequency which is an exact fraction of the frequency of the first pulse output (110). A high speed and a low speed spark advance transfer unit each include a retriggerable monostable circuit (127, 136) coupled to a latch circuit (133, 142) to selectively operate a modifying circuit (145, 164) to provide control signals to the ignition system (81) to provide a rapid spark angle advance at preselected speeds.
摘要:
A power unit (79) includes a spark advance unit (80) connected to a solid state ignition system (81) for selectively supplying ignition sparks to operate an internal combustion engine (83). A pulse generator (107) responds to a series of negative polarity half-cycle alternations (96) provided by an alternator winding (20') to provide a first pulse output (110) of a first frequency. A pulse counter (119) counts the pulses of the first pulse output (110) to provide a second pulse output (120) having a second frequency which is an exact fraction of the frequency of the first pulse output (110). A pair of counters (162, 141) selectively accumulate constant frequency pulses from an independent oscillator (127), as selectively controlled by the first and second pulse outputs (110, 120), to establish high and low speed advance points which are inter-related by a fixed numerical ratio. A pair of latch circuits (170, 149) are respectively connected to respond to one of the first and second pulse outputs (110, 120) and to the count status of one of the counters (162, 141) to selectively operate a modifying circuit (203, 180) to provide control signals to the ignition system (81) to provide a rapid spark angle advance at preselected speeds.
摘要:
A speed sensor (90) of a high speed spark advancer (80) responds to the input voltage pulse on the primary winding (92) of a spark inducing ignition transformer (92a) to provide a single speed responsive pulse (115) during each complete operating cycle of an alternator driven ignition system (81). A speed switch (94) responds to each speed responsive pulse (115) to selectively transfer between a first condition when the engine (83) operates within a predetermined high speed range and a second condition when the engine (83) operates below the predetermined high speed range. A spark advance control (95) responds to the first condition to provide a modifying input to the ignition system (81) to provide a high speed advanced spark angle (168) and responds to the second condition to vary the modifying input to provide a second spark angle (169). The high speed spark advancer (80) provides a rapid transition (170) from the high speed advanced spark angle to the second spark angle to reduce the likelihood of detonation within the engine (83).
摘要:
In an internal combustion engine in which the fuel supply is interrupted during no-load operation to save gas the ignition timing is retarded following resumption of the fuel supply to cause the resumed torque to be applied slowly. A sequence of ignition timing signals following the activation of the gas pedal is delayed by sequentially smaller and smaller amounts until the normal ignition timing is resumed.
摘要:
An electronic ignition control device for determining and maintaining a vehicle at the optimum spark advance for different ranges of crankshaft rotation speeds and ratios of air intake to crankshaft rotation speed. Signals indicating a range in which the instantaneous rotation speed falls and a range in which air intake/speed ratio falls define a ROM address at which is stored an optimum spark advance angle for that combination of ranges. The signal indicating the stored angle is applied to a discriminator which also receives inputs from a crank switch monitor, a throttle switch monitor and a coolant temperature sensor. When cranking or idling is detected, the discriminator substitutes a cranking advance or idling advance angle for the stored optimum advance angle signal.
摘要:
It is discriminated in an ignition timing control system for an internal combustion engine whether the ignition timing arithmetically calculated on the basis of sensed operating conditions of the engine lies within a predetermined range of ignition timing. When the result of discrimination indicates that the calculated ignition timing lies within the predetermined range, ignition occurs at that instant, while when the result of discrimination indicates that the calculated ignition timing does not lie within the predetermined range, the result of calculation is disregarded, and ignition occurs at a predetermined instant.
摘要:
The composition of exhaust gases from an IC engine is dependent on ignition timing; to control the composition, therefore, ignition timing is adjusted in accordance with sensed exhaust gas composition signals. To prevent abrupt change of ignition timing, as the exhaust gas composition signal changes upon change of exhaust gases between reducing and oxidizing state, a limit stage is included which limits the change of ignition timing between succeeding ignition events to a predetermined incremental crankshaft angle, for example 2.degree.. The ignition angle adjustment may be nonsymmetrical in adding and subtracting direction, and, in any event, is limited to a maximum adjustment angle beyond which undesirable or unsafe operating conditions of the engine might obtain. In a preferred digital form, the count number of an accumulator counter, the output signal of which determines the occurrence of an ignition event, is modified, in said incremental steps, to thereby control the timing of the ignition event.
摘要:
An electronic spark timing advancing apparatus for an internal combustion engine having an ignition device is disclosed, wherein a crank angle at which an internal pressure of a cylinder of the engine assumes a peak value is detected and a desired crank angle at which the internal pressure of the cylinder is to assume a peak value under a given condition is calculated in accordance with that condition, and a spark timing of the ignition device is controlled in response to a deviation therebetween to minimize the deviation.
摘要:
An electronic ignition timing control system for an internal combustion engine which comprises a rotational angle detector for detecting a rotational angle of the engine to produce output pulses, a reference angle detector for detecting a reference rotational angle of the engine to produce a reset pulse, an ignition angle computing circuit for converting by interpolation the advance angles corresponding to principal points of engine parameter address into the retard angles from the reference angle to produce a first output signal indicative of an angle corresponding to the rotational angle of the engine and a second output signal indicative of the delay time corresponding to an angle smaller than the first output signal value, a first comparator to digitally compare the first output value of the ignition angle computing circuit with the number of the output pulses of the rotational angle detector, and a second comparator to convert the second output value of the ignition angle computing circuit into a time period whereby the instant that the conversion is completed is selected as desired ignition timing.