Abstract: An ignition system for an internal combustion engine includes an ignition coil coupled to a spark plug in a combustion chamber of the engine, and a switch responsive to an ignition control signal for causing a primary current to flow through a primary winding of the ignition coil. A control circuit is configured to generate the ignition control signal so as to produce a plurality of sparks at the spark plug during a combustion event in the cylinder. A combustion detection circuit in sensing relation with the combustion cylinder is configured to generate a combustion detect signal when combustion occurs. The control circuit is further configured to terminate the generation of the ignition control signal during the combustion event in response to the combustion detect signal, thereby terminating multicharge operation when the need for further sparks is no longer present. Unnecessary spark plug wear is avoided.

Abstract: An interface device for interfacing a pencil coil to a spark plug is provided. The interface device comprises a substantially C-shaped spring adapted to mechanically and electrically engage a pencil coil shield and also adapted to make electrical contact with a spark plug ground while the spring remains mechanically and electrically engaged to the pencil coil shield. Also provided is a pencil coil shield assembly for interfacing a pencil coil to a spark plug. The pencil coil shield assembly comprises a substantially cylindrical pencil coil and a spring. The substantially cylindrical pencil coil shield is adapted to surround the pencil coil. The spring is mechanically and electrically engaged with the pencil coil shield and is adapted to make electrical contact with a spark plug ground while the spring remains mechanically and electrically engaged to the pencil coil shield.

Abstract: A detector of position of rotation of a target wheel via the outputs of a differential sensor employing two matched MRs to extract position of rotation information from the target wheel. The target wheel is provided with wide and narrow slots or teeth circumferentially arranged such that, for example, 24 zones are created wherein each zone ranges from the center of a wide slot to the center of a narrow slot, and wherein each zone occupies 15 degrees circumferentially. The two matched MRs of the sensor are powered by matched current sources and matched magnetic biasing and are aligned in the circumferential direction of the target wheel. The MRs generate two angularly offset signals from the passage of a single slot (or tooth) of the target wheel which are input to a signal conditioning circuit. Within the signal conditioning circuit, the two sensor signals are differentially amplified to produce a differential signal whereby the width of the slot is used to encode a binary position pulse.

Abstract: An apparatus for detecting a combustion condition such as misfire in an internal combustion engine. During an initial charging operation, a make voltage is developed across a secondary winding of the ignition coil, and thence across the electrodes of a spark plug. After combustion, the ignition coil is recharged to thereby again develop the make voltage across the secondary winding to bias the spark plug. The make voltage provides the bias across the spark plug electrodes to cause an ion current flow if combustion has in-fact occurred. The ion current is sensed with a sensing resistor.

Abstract: A system and method of providing multicharge ignition are provided. The method and system preferably are adapted to trigger at least some of the multicharge events of the system and method in a current-dependent manner. Preferably, existing power train control units (PTCUs) can be used with the system and method, without the need for signals other than the timing signal (e.g., EST pulse) from the PTCU.

Abstract: A biasing circuit for an ion current measurement system draws power from a primary side of the ignition coil, and applies a positive polarity bias voltage to a low voltage side of a secondary winding of the ignition coil. The biasing circuit includes a silicon-controlled rectifier (SCR) which has an on state for carrying spark current during a spark interval of operation, and further includes an off state which prevents the stored biasing voltage on a capacitor from being shunted to ground, thereby allowing ion current sensing through the low voltage side of the secondary winding. The low on-state voltage drop of the SCR during conduction of spark current minimizes losses of spark energy.

Abstract: An ignition control system for an internal combustion engine includes a control circuit, an ignition coil, a switch, and a sensing circuit. The control circuit is configured to interrupt a primary current, thereby establishing a secondary current which is discharged to cause a spark plug coupled to the secondary winding to produce a first spark. The sensing circuit is configured to generate a secondary current signal representative of a level of secondary current. The control circuit is responsive to the secondary current signal to terminate the discharge by closing the switch to cause the primary current to again flow in preparation of a second spark. The termination of the discharge occurs when the secondary current level reaches a secondary current threshold which is determined as a function of engine speed and ambient temperature.

Abstract: A method and apparatus for detecting an engine crankshaft angular position which provides for fast starting of the engine. A target wheel and sensor combination generate an analog signal which is convened into a 24 bit digital output which repeats every 360.degree. rotation of the crankshaft. Each bit represents a particular angular position of the crankshaft. Any 6 sequential bits in the repeating 24 bit digital output sequence form a unique pattern. By monitoring the first six bits generated (90.degree. of crankshaft rotation) during startup, a crankshaft angular position can be determined, thereby enabling fast starting of the engine.

Abstract: A solenoid for an electric starter. The solenoid has a metal case that contains a coil winding assembly. The coil winding assembly includes a plastic coil spool that carries a pull-in coil and a hold-in coil. One end of the coil spool supports a plurality of axially extending metallic threaded studs that are insert molded into the end of the coil spool. The end leads of the coils are wrapped around the studs and welded thereto. The studs, together with nuts that are threaded onto the threaded portions of studs, serve to secure a plastic cover to an end of the metal case.

Abstract: A plurality of electrical load switches of the type operable to at least two operating conditions by the actuation of an operating member are connected in respective motor vehicle load circuits and are mounted in a switching unit having an actuating mechanism for actuating the switch operating members that is selectively locatable in each of a plurality of switch operating positions in each of which it is in register with an operating member. The switching unit is controlled by a microprocessor that effects the locating of the actuating mechanism in the switch operating position in which it may actuate the operating member of a load switch selected to be operated and the operating of the actuating mechanism when so located in response to function select electrical signals that indicate the load switches selected for operation.

Abstract: A plurality of individual electrical load switches each having an operating tab are so mounted and oriented that the operating tabs extend toward a central axis to define a circle substantially normal to the central axis and operate substantially in the direction of the central axis. An operating arm having ends thereof arranged to be brought into register with each operating tab at mutually exclusive angular positions is normally tilt mounted in a first direction upon a rotor that may be positioned in selected ones of a plurality of angular positions by a step motor. Upon one end of the arm being brought into register with a switch operating tab, the arm is tilted in the opposite direction to effect the operation of the operating tab with which the one end thereof is in register to place the corresponding individual electrical load switch in a selected circuit condition.