Abstract: A voltage regulator for an internal combustion engine having a permanent magnet alternator and utilizing an SCR/diode bridge rectifier includes crowbar SCR overvoltage protection means. To assure that the crowbar SCR has an adequate period in which to cool off after being triggered on by an overvoltage surge, crowbar SCR operation is detected to generate a control signal to activate a timer which shuts off gate drive to the main bridge SCR's and thereby shuts down the bridge for a period of time sufficient to provide crowbar SCR recovery and cool off. In its preferred embodiment, the control signal is provided by the crowbar SCR gate to cathode voltage drop during protective operation, which signal is of relatively long duration, thus allowing the use of filters to eliminate spurious triggering of the timer by transient noise signals. Feedback from the switch means supplying gate drive to the bridge SCR's is used to provide a tapered charging characteristic.

Abstract: A system and method for its implementation for suppressing RFI effects on an electronic control module enclosed in a metal housing includes inserting a plurality of high frequency shunts in the wires attached to the module through the housing. The shunts, comprising by-passing capacitors include one capacitor on the incoming wire disposed closely adjacent the housing and grounded thereto and another capacitor on each wire disposed closely adjacent the connection of the wire to the active circuit of the module and grounded to the circuit ground network. The housing includes a direct connection to ground and the ground network for the electronic module has a single ground connection to the housing.

Abstract: A self-protective driver circuit with automatic reset features is provided for a marine electric fuel pump (2, 102) energized by the boat battery (4, 104) as controlled by a series connected semiconductor switch (6, 106). A first stage protective subcircuit (28, 128) senses surge current through the semiconductor switch at initial turn on with the fuel pump at rest and causes the semiconductor switch to depart from saturated conduction and thus limit the current until the pump starts running and the current decreases to a safer level, to protect the semiconductor switch from excessive current.

Abstract: An annular permanent magnet rotor (8) is mounted around and fixed to a crankshaft (4) of an internal combustion engine (2) and has a plurality of circumferentially spaced magnetic poles (14) of sequentially alternating north-south polarity type, and a pole (18) reversed out of the alternating sequence. A first fixed stator (24) is provided by an annular ring concentric to the rotor (8) and has a plurality of poles (26) for magnetic flux coupling with the permanent magnet rotor poles (14). A second fixed stator (48) is axially spaced from the first stator (24) and has a pair of poles (50, 52) for magnetic flux coupling with the rotor (8). A first sensor coil (40) around the first stator (24) outputs a timing angle signal. Processing circuitry produces a series of digital pulses having ANGLE-defining edges occurring at fixed angular increments of crankshaft rotation.

Abstract: The invention provides a modular ignition system using a separate ignition module (16) for each engine cylinder. The modules (16) can be arranged for use with engines having differing numbers of cylinders.Each module (16) includes a main capacitor (22) to be charged by the engine's alternator (11). The main capacitor (22) is discharged through a main silicon controlled rectifier (23) into an ignition transformer (28) to provide a high voltage pulse to fire a spark plug (15). A pilot capacitor (26) is also charged by the alternator (11) to provide power to a pilot SCR (36). The pilot SCR (36) has its gate connected to a trigger winding (14) in the alternator (11) to discharge the pilot capacitor (26) into the gate of the main SCR (23) to fire the spark plug (15).The pilot capacitor (26) is also connected to the cathode of the main SCR (23).

Abstract: The invention provides charging control circuitry (20) for a capacitor discharge ignition system (10) having power capacitors (21) connected to be discharged by main electronic switches such as SCR's (23) into ignition transformers (24) to sequentially fire the engine's spark plugs (16). The charging control circuits (20) each include a charging SCR (26) to limit charging current flow to the main capacitor (21), unless a discharge pulse into the ignition transformer (24) has occurred in the recent past. Thus if a short circuit in either the main capacitor (21) or main SCR (23) in one of the ignition circuits (19) prevents that ignition circuit from properly functioning, the charging SCR (26) will limit the flow of charging current to the defective circuit and allow the other ignition circuit (19) to receive charging current. The gate of the charging SCR (26) is controlled by an amplified signal from a memory capacitor (28) which is charged by the discharge pulse from the corresponding ignition circuit (19).

Abstract: 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.

Abstract: 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.

Abstract: 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).

Abstract: A solid state ignition system is provided for a two cycle internal combustion engine. A low speed limiter unit includes an electronic spark advance controller means connected to the ignition system to automatically advance the ignition angle by a substantial amount below a desired low limit speed. A speed sensing means is connected to sense the engine speed and at the selected minimum engine speed actuates the advance controller. The advance controller preferably has an asymmetrical rate of response, producing a relatively rapid advance output and a relatively slow retard output in response to changes in the speed sensing means.

Abstract: A tachometer circuit for an engine having an alternator driven capacitive discharge ignition system functions as a frequency-to-current converter converting each ignition capacitor discharge into a precisely controlled amount of electric charge, which is then passed thru an indicating microammeter movement graduated in RPM. The precisely controlled electric charge is developed in a charge transfer capacitor, with the peak voltage appearing across the capacitor being regulated by a programmable transistorized voltage regulator. The temperature coefficient of the charge transfer capacitance is neutralized by the temperature coefficient of the voltage regulator, such that the product of capacitance multiplied by voltage--which is equivalent to charge--remains constant. The precisely controlled charge is initially established by machine trimming of a voltage--determining resistor in the voltage regulator, thereby allowing practical large volume manufacture of the circuit from unmatched components.

Abstract: The invention contemplates a capacitor-discharge ignition system which includes a particular low-resistance, low-inductance, wire-wound circuit element at the spark plug which is operative with the spark plug and with the rest of the ignition system to materially suppress RFI generated at the spark gap. In application to high-speed, high-power two-cycle engines, use of the invention does not adversely affect engine performance.

Abstract: In an internal combustion engine an automatic fuel pump switch connects a fuel pump motor to the battery. An electronic sensing circuit is connected to the output winding of an engine-driven alternator which is also connected to charge the battery. The sensing circuit includes a sensing transistor connected to continuously sense the two instantaneous voltages relating to ground that appear as alternating current (A.C.) voltages at the opposite ends of the alternator output winding and produces an output only when one voltage is above a selected positive level while the other voltage is lower than the first voltage by a minimum amount. A control transistor circuit is connected to the output of the sensing transistor and is turned on to operate the fuel pump only when the engine is turning over at a sufficient rate to start and run.

Abstract: An alternator driven capacitive discharge ignition system includes a tachometer circuit monitoring the speed-dependent repetition rate of discharge at an internal trigger power supply, the tachometer circuit causing the triggering threshold bias to be reduced below idle speed to electronically advance the timing. The ignition circuit includes a triggering threshold bias capacitor in series the trigger pulse source and a trigger power supply having a pilot capacitor to alternately fire a pair of ignition silicon controlled rectifiers. The pilot capacitor is charged in series with an RC filter network of a "bucket" tachometer circuit to create a speed signal voltage proportional to engine speed with the pilot capacitor functioning as the bucket capacitor. The speed signal is a voltage which is positive relative to a common signal ground while the threshold bias capacitor voltage is negative relative to such signal ground.

Abstract: Ignition in a six-cylinder internal combustion engine is supplied by a pair of similar alternator-driven, alternate-firing, capacitor discharge ignition systems, each discharged to the several spar k plugs of its own three cylinders by individual controlled rectifiers. A common trigger pulse generator is magnetically coupled to the engine flywheel and includes three individual trigger coils for generating properly referenced and angularly spaced pulses, each coil producing alternating positive and negative polarity pulses. A steering diode network connects one end of each triggering coil to a related controlled rectifier for an associated spark plug in one cylinder group and the opposite end of each coil to the controlled rectifier for a spark plug in the second cylinder group.

Abstract: An ignition wiring system having the leads formed as a wire coil about a magnetizable core defines a distributed constant resistive-inductive series impedance. A metal shield is located over the spark plug proper and electrically connected to the engine ground. A flexible shield extension in the form of a coil extends over the lead from beneath the shield. The shield and shield extension introduce distributed capacitance between the special lead and engine ground. The combination of the shield and shield extension with the special lead forms a distributed constant RLC filter which produces RFI suppression. The shield and shield extension confine the electromagnetic radiation emanating from that portion of the lead where the radiation is strongest, thereby enhancing the suppression. The rapid discharge by the spark plug of the stored energy contained in the distributed capacitance increases the spark intensity and promotes more complete combustion.

Abstract: A two cylinder, two cycle engine for an outboard motor includes an alternator driven, capacitor discharge ignition system. The alternator includes an annular permanent magnet secured within a flywheel skirt and includes a pair of circumferential opposite poles with diametrical spaced neutral areas. The magnet is a flexible ferrite strip with a butt joint at one of the neutral areas. A stator assembly is mounted within the annular rotor and includes a semicircular core with a charging coil at each end. Each movement of the magnetic gap means past the coils generates a pulse. A trigger coil within a housing is mounted in coplanar relation between the charging coils, with a pole aligned with and spaced from the stator core. The housing is rotatably mounted and includes an integral cam for positioning a throttle lever.