Abstract: An anti-theft device for automobile vehicles disables the vehicle's starter ignition system unless a coded resistive element is inserted into the device by the vehicle's operator. A control system senses the value of the coded resistive element and enables the starter system if the sensed value is correct. A latching circuit latches-in enablement of the starter system after an arming switch is activated and the resistive element has been removed, serving to provide a valet function. A lock-out circuit prevents enablement of the starter system for a prescribed time period following an unauthorized attempt at enabling the system, as when an incorrect resistive element is inserted into the device. The device employs a normally closed relay to enable the starter system so that failure of those portions of the device which are most likely to fail does not affect normal operation of the starter system.

Abstract: A voltage controlled oscillator for the conversion of a ratiometric analog signal into a digital signal is disclosed. The oscillator generates a square wave whose frequency is a function of the magnitude of the analog signal input. The variable frequency wave is generated by a comparator receiving high and low threshold levels from a network for comparison with a ramping voltage developed by a timing element. An increasing ramp is provided by a current source whose output is proportional to the analog signal and a decreasing ramp rate is provided by a current sink whose output is similarly proportional to the analog input signal. Because the analog input signal is ratiometric with variations in the power supply voltage, the ramp rates change with these variations, however the high and low threshold levels also change with variations in the supply voltage thereby the comparator generates a square wave output at a frequency independent of these variations.

Abstract: An actuation timing apparatus is disclosed for providing triggering and steering control signals to an electronic control unit regulating a plurality of solenoid fuel injectors of a sequential injection system. The apparatus includes a rotatable member which is rotated in synchronism with the engine at the speed of its camshaft. The rotatable member has a plurality of spaced sensible elements geometrically disposed thereon and divided into groups identifying individual cylinders. Each group has at least one sensible element which defines a reference element having a recognizable characteristic distinguishing it from the other sensible elements in the group. A single sensor senses the spaced sensible elements of each group as they rotate past a fixed sensing location and generates corresponding electrical pulses to a pulse processing circuit. The pulse processing circuit decodes each group of pulses to provide the identity of the injector to be next actuated.

Abstract: Electric control apparatus for providing an enabling control signal and a steering control signal to control the electronic fuel injectors of a sequential fuel injection system of an internal combustion engine is disclosed. The apparatus includes a rotatable disc which rotates in synchronism with the engine. The disc has a plurality of spaced sensible elements contained thereon, one of the sensible elements defining a reference element which has a recognizable characteristic distinguishing it from the other sensible elements. The distance between the reference element and an adjacent element defines a predetermined distance different than the distance between any two adjacent nonreference elements. A single sensor senses the spaced sensible elements and provides corresponding electrical pulses. A pulse processing circuit electrically connected to the output of the sensor processes the pulses.