Abstract: A system for use with an internal combustion engine which reduces, or eliminates, engine knock and attendant engine damage. An audio transducer is placed on an engine cylinder to convert audio signals occurring within the combustion chamber into an electrical signal. This signal is sampled and filtered and the amplitudes of two time-sequenced segments are compared. One of those segments is timed for an interval during which detonation, if any, is likely to occur, and the other of these segments is timed for an interval during which no detonation is likely to occur. When the amplitude of the sample from the segment of likely detonation exceeds the amplitude of the sample from the segment of unlikely detonation, by a predetermined amount, extra fuel is momentarily added to the combustion chamber to slow down the rate of combustion and cool the walls of the combustion chamber.

Abstract: An electronically controlled fuel-injection system for an internal combustion engine, wherein fuel injection control pulses drive associated fuel injectors for delivering fuel to the internal combustion engine. A fuel pump delivers fuel from an associated fuel tank to the fuel injectors and a pressure regulator associated with the fuel tank maintains a pressure differential across the fuel injectors. Exhaust back pressure from the internal combustion engine is applied to the pressure regulator, such that the pressure differential across the fuel injectors varies in response to pressure changes in exhaust back pressure. A linear relationship between exhaust back pressure and the pressure differential across the fuel injectors provides an inexpensive and accurate electronic fuel injection control system.

Abstract: A self-adaptive fuel control system for an internal combustion engine which provides maximum fuel economy by maintaining engine operation at a preselected point on the r.p.m. vs. fuel flow curve. Engine operation is maintained at the preselected point by sampling initial steady state engine speed, leaning the fuel mixture supplied to the engine until there is a predetermined drop in engine speed, enriching the fuel mixture to attain an increase in engine speed, resampling engine speed and then repeating the process.

Abstract: A control system for a feedback carburetor in which a controlled vacuum is applied to the carburetor fuel bowl to reduce the fuel flow rate and provide maximum fuel economy. Engine speed is monitored and reduced a predetermined amount during steady state cruising through use of an air control solenoid to apply the controlled vacuum. The controlled vacuum is removed during acceleration or when engine speed is outside the range of steady state cruise speed.

Abstract: A control system (17) for cathodically protecting an outboard drive unit (11) from corrosion includes an anode (12) and a reference electrode (13) mounted on the drive unit (11). Current supplied to the anode is controlled by a transistor (20), which in turn is controlled by an amplifier (25). The amplifier is biased to maintain a relatively constant potential on the drive unit (11) when operated in either fresh or salt water.

Abstract: The invention contemplates fuel flow monitoring apparatus used in conjunction with an electronic fuel injection circuit for an internal-combustion engine. Electronic fuel injection circuits have vastly improved engine performance and efficiency, but their effectiveness has been hampered by the fact that fuel flow has in the past been monitored by mechanical fuel flow sending units. The instant invention eliminates the need for a mechanical fuel flow sending unit and replaces it with electronic circuitry which provides both an indication of fuel flow rate and total fuel consumption. The system also provides the diagnostic capability of monitoring fuel flow rate while the engine is not running.

Abstract: An electrode apparatus (15) is provided for mounting an anode (17) and reference electrode (19) of a cathodic protection system on an outboard drive unit (10). The apparatus includes an insulating housing (20) on which the anode (17) and reference electrode (19) are mounted and a copper shield (30) mounted between the anode (17) and electrode (19) to allow them to be mounted in close proximity to each other. The shield (30) is electrically connected to the device to be protected and serves to match the electrical field potential at the reference electrode (19) to that of a point on the outboard drive unit (10) remote from the housing (20).

Abstract: The invention contemplates an electronic control unit in the form of a square-wave generator to serve the function of throttle and enrichment control in a fuel-injected internal-combustion engine. The output of the square-wave generator is an appropriately timed succession of square-wave pulses, of width (in terms of crankshaft rotation) which currently reflects computed evaluation of inlet-air temperature and pressure, engine speed, and start-up running condition of the engine. Under conditions of cold starting the pulse width of the square wave pulses is increased to provide fuel enrichment and, dependent upon engine throttle position the frequency of the square wave pulses may also be increased to provide additional fuel enrichment.

Abstract: A low fuel pressure monitor (25) for a two cycle engine (12) having an operating piston (21) initially cooled by pressurized fuel senses the fuel pressure at an output (18) of a fuel pump (14) and the operating speed of the engine (12) as sensed at an output (30) of an alternator (24) to provide an alarm (31) in response to a sensed low fuel pressure condition existing for a predetermined period of time while the engine (12) is operating above a predetermined speed. A circuit (99) senses an improper polarity connection of a battery (96) to provide a second type of an alarm.

Abstract: The invention provides an energy regulating system for regulating the electrical energy generated by the coil (11) of an alternator and used to charge a battery (12). A full wave bridge rectifier circuit (13) supplies direct current to the battery. A comparator (25) is connected to the positive terminal of the battery to provide an output when the battery charge is below the desired level. The output of the comparator is connected through a photo coupler (33) to control the main SCR (18) and thus control the charging current to the battery.

Abstract: An energy regulating system (21) includes a battery (25) connected to a single phase generator winding (23) through a connecting circuit (24) providing a full wave bridge rectifier (26) having a pair of controlled rectifiers (69, 71) which are selectively gated into connection in response to the sensed phase angle of the energy in the winding (23). A control (54) operates in response to a charge sensor (31) which senses the charge on the battery (25) and a phase sensor (79) which senses the energy phase at the winding (23) to operate a switch (44) to modify the operation of the bridge circuit (26) to interrupt the energy flow to the battery (25). An excessive energy sensor (80) responds to excessive sensed energy at the connecting circuit (24) to turn on a pair of controlled rectifiers (53, 70) to deactivate the bridge circuit (26) to prevent damage to the connecting circuit (24).

Abstract: The invention contemplates engine shut down protection apparatus used in conjunction with an electronic fuel injection circuit for a water cooled internal-combustion engine. When turning off water-cooled internal combustion engines equipped with typical electronic fuel injection systems both the fuel supply and the ignition circuit are disabled. As the engine speed decreases the engine block cools faster than the pistons since the block is water cooled and this uneven cooling may result in damage when the engine is shut down at high speed. The instant invention maintains the fuel supply to the pistons after engine shut down to cool and lubricate the pistons and prevent possible engine damage.

Abstract: An electronic control circuit for a fuel injected internal combustion engine in which fuel flow is alternated among selected engine cylinders at low speed engine operation. Alternate fuel delivery results in improved idle, fuel economy and reduced emissions. Conventional engine operation is progressively restored as the engine approaches high speed operation.

Abstract: The invention contemplates atomization compensation apparatus used in conjunction with an electronic fuel injection circuit for an internal-combustion engine. For four cycle engines, operating at low engine speed the fuel has a tendency to fall out of suspension in the intake manifold especially when the intake manifold air-temperature is low. The instant invention gradually increases the fuel flow to the engine as an inverse function of low engine speed and intake manifold air temperature to provide atomization compensation.

Abstract: An internal combustion engine employs an alternator driven capacitor dishcarge ignition system wherein a stator coil assembly provides power pulses to charge the capacitors and an adjustably positionable coil assembly provides electrical pulses whose frequency and magnitude (bias voltage) are related to engine speed and effect ignition timing i.e., capacitor discharge. An electronic solid state ignition timing and detonation controller is connected to the capacitor discharge ignition system and operates in response to the pulses from the high speed winding of the aforesaid stator coil assembly to supply a bias signal which reduces the aforesaid bias voltage from the said other coil assembly at higher engine speeds thereby providing additional spark advance, depending upon engine speed and detonation severity. The electronic controller improves engine efficiency at cruising speeds and reduces detonation at high speeds.

Abstract: The invention contemplates an electronic control unit in the form of a square-wave generator to serve the function of throttle and enrichment control in a fuel-injected internal-combustion engine. The only input manual control is a "throttle" displacement, and the output is an appropriately timed succession of square-wave pulses, of width (in terms of crankshaft rotation) which currently reflects computed evaluation of inlet-air temperature and pressure, engine speed, and start-up vs. running condition of the engine.

Abstract: A marine cathodic protection system maintains a submerged portion of a marine drive unit at a selected potential to reduce or eliminate corrosion thereto. An anode is energized to maintain the drive unit at a preselected constant potential in response to the sensed potential at a closely located reference electrode during normal operations. Excessive current to the anode is sensed to provide a maximum current limitation. An integrated circuit employs a highly regulated voltage source to establish precise control of the anode energization.

Abstract: An energy regulating system includes a D.C. battery electrically connected to a single phase winding of an A.C. generator through a full wave rectifying circuit. An SCR switch is directly connected in parallel to a Zener diode forming one bridge leg to selectively short circuit such Zener diode when the battery voltage exceeds a predetermined level. An integrated circuit includes a voltage comparator providing an independent, substantially constant reference signal which is compared to battery potential to provide a temperature independent gating output to the control SCR. The integrated circuit provides current limiting to maintain the gating signal within a predetermined magnitude.

Abstract: The invention contemplates electronically controlled fuel-injection for a multiple-cylinder two-cycle internal-combustion engine wherein each cylinder has its own independent crankcase region in which to receive and compress inlet air and fuel, prior to delivery of combustible mixture to the head or combustion end of the cylinder. Fuel is injected into each crankcase region during only a portion of the stroke involving induced intake of air therein, i.e., during only a portion of the rise of each piston in its approach to top-center position, and while pressure within the crankcase region is relatively uniform. The time-duration of actual injection is relatively short, thus enabling a plurality of different cylinder injections to be made concurrently, resulting in simplification of fuel-injection control circuitry.

Abstract: The invention contemplates electronically controlled fuel-injection for a single or multiple-cylinder two-cycle internal-combustion engine wherein each cylinder has its own independent crankcase region in which to receive and compress inlet air and fuel, prior to delivery of combustible mixture to the head or combustion end of the cylinder. Fuel is injected directly into each crankcase region during only a portion of the stroke involving induced intake of air therein, i.e., during only a portion of the rise of each piston in its approach to top-center position, and while pressure within the crankcase region is relatively uniform. The time-duration of actual injection is relatively short, to enable identical injections in each cylinder, each such injection being identically timed with relation to position and displacement of its associated piston.