Abstract: A method of regulating an electromagnetic actuator is disclosed. The electromagnetic actuator has an electromagnet; an armature movable, in a switching step, by a controlled current supply to said magnet coil, from a first armature position to a second, pole face-engaging armature position against a force of a resetting spring. The method includes the following steps for regulating the current flow through the magnet coil to set a low velocity of the armature as it arrives at the pole face: during the switching step, detecting the energy amount in the electromagnetic actuator by detecting a changing armature position and/or a changing armature velocity; estimating by extrapolation the expected energy amount upon arrival of the armature on the pole face; and forming a coarse correcting value by comparing the estimation to be extrapolated with a predetermined target value selected with an aid of the total energy stored in the system in the second armature position.

Abstract: A recirculating driver control circuit for an electrically operated device has a power supply and a controller coupled to the power supply and the device. The controller generates an on/off signal through a first output. The on/off signal has an ON state and an OFF state. The controller generates a pulse width modulated signal through a second output. The pulse width modulated signal has a first state and a second state. A first switching device is coupled to the first output of the controller and the device and receives the on/off signal. The first switching device conducts when the on/off signal is in the ON state. A second switching device is coupled to the second output of the controller and the electrical device. Energy is supplied to the device when the pulse width modulated signal is in the first state and the on/off signal is in the ON state. The device recirculates energy to power supply when the pulse width modulated signal is in the second state and the on/off signal is in the ON state.

Abstract: A method is provided to control velocity of an armature of a fuel injector as the armature moves from a first position towards a second position. The fuel injector includes a stator core at the second position and a coil is associated with the stator core. The coil, the stator core and the armature define a magnetic circuit. The coil generates a magnetic force to cause the armature to move towards and impact the stator core. The method includes energizing the coil to permit the armature to move towards the stator core. A rate of change of magnetic flux of the magnetic circuit is determined. Closed loop feedback control of the determined rate of change of magnetic flux is used to regulate a rate of magnetic flux by controlling current to the coil so as to control a velocity of the armature upon impact with the stator core.

Abstract: An injector drive circuit capable of driving an injector of an internal combustion engine without using a DC-DC converter expensive. The injector drive circuit includes a power circuit for converting a voltage outputted from a magneto mounted on the engine into a DC voltage, a capacitor charged with a voltage accumulated in a voltage accumulator, a drive current feed circuit for applying a voltage across the capacitor to a solenoid coil to feed a drive current to the solenoid coil when it is fed with an injection command signal, and a holding current feed power supply section for feeding the solenoid coil with a holding current required for keeping a valve open after the drive current fed from the capacitor to the solenoid coil passes a peak value.

Abstract: A driver circuit is provided for an electromagnetic fuel injector having a coil and powered by a supply voltage. The driver circuit includes a comparator to control activation current to the coil of the fuel injector and transistor structure operatively associated with the comparator and constructed and arranged, together with said comparator, to maintain a hold current of the coil at a constant level slightly above a minimum current required to open the injector, regardless of the supply voltage value. The transistor structure includes first, second, and third transistors. The first transistor is arranged to receive an output of the comparator and to provide a constant current to the second transistor regardless of a value of the supply voltage. The second transistor is operatively associated with the supply voltage and with a high end of the coil. The third transistor is electrically connected to the lower end of the coil so as to sense, in conjunction with a resistor, a current in the coil.

Abstract: A fuel injector apparatus includes an electromagnetic fuel injector having a housing and a magnetic circuit in the housing. The magnetic circuit including an electromagnetic coil constructed and arranged to operate at a nominal voltage to open the fuel injector. The nominal voltage is substantially less that a supply voltage. Circuit structure is electrically coupled with the coil and is constructed and arranged to step-down the supply voltage to be substantially the nominal voltage at the coil.

Abstract: A method and apparatus for power reduction in the operation of a power circuit for a relay or other electro-mechanical device having a first (higher) power requirement for the device to be activated, and a second (lower) power requirement for the device to be maintained includes charging a power supply capacitor to the necessary voltage for the first power requirement while the device is not activated, supplying current from the power supply capacitor to the device when it is activated until the voltage reaches the second power requirement, and keeping the power supply capacitor voltage at that second power requirement to maintain activation of the device.

Abstract: Motion recognition processes are disclosed, in particular for regulating the impact speed of an armature on an electromagnetic actuator with at least one electromagnet having at least one pole face (4) and connected to a controllable power supply, and with an armature (5) connected to a regulating element to be actuated which when power is supplied to the electromagnet, is moved against the force of a restoring spring (7) in the direction of the pole face of the electromagnet from a first switching position to a second switching position in which it stops against the pole face. At least one sensor (11) detects in a defined air gap zone of the pole face a progressive attenuation of the magnetic field as the armature approaches and generates a corresponding signal.

Abstract: The fuel injection valve controller steadily detects the completion of opening of the fuel injection valve or the completion of the needle valve lifting movement. A current flowing through the electromagnetic coil 4 which drives the fuel infection valve, is measured based on the voltage difference V across the resistor R6 connected in series with the coil 4. The circuit 21 emphasizes changes in the coil current. The signal V2 representative of emphasized coil current is supplied to the current change detecting circuit 22 which generates the output signal V3 when the coil current or voltage signal V2 temporarily decreases. The signal V3 is compared with the reference voltage Vref to issue the signal S3 showing the full opening of the fuel injection valve.

Abstract: Control circuit for electromagnet with two coils used to determine a call phase and a hold phase, and powered from a DC power source. The energy source comprises a current generator and a capacitor powered by this current generator. A control device controls two switches, in which the first switch controls discharge of the capacitor in the first coil during the call phase, and the second switch sets up current passing through a second coil during the call phase and the hold phase. The required current output from the current generator is thus reduced.

Abstract: A method and device are described for driving an electromagnetic consumer, which includes a movable element. This element includes a solenoid-operated valve for controlling the metering of fuel into an internal combustion engine. A switching instant is determined within a timing window. Within the timing window, the voltage being applied to the consumer is able to be controlled to an adaptable setpoint value in open and/or closed loop.

Abstract: A contactor comprises first and second armatures which are urged towards contact-making positions by first and second windings, respectively. Each of the armatures displaces the other armature from its contact-making position when moving towards its own contact-making position. A controller actuates each of the windings before deactuating the other of the windings.

Abstract: During the low load operation, this fuel injection control device reduces the initial armature displacement speed of the solenoid actuator that drives the open-close valve against the low fuel pressure in the balance chamber, thereby lowering impact noise produced in the solenoid portions. When the engine is determined to be idling, a command pulse width which energizes the solenoids of the solenoid actuator is calculated according to the target injection amount, the common rail pressure, and the target fuel injection timing. Since the initial period of the command pulse width, i.e., pull-in current conduction period, is set shorter than the pull-in current conduction period for the high load operation of the engine, the initial armature displacement speed of the solenoid becomes relatively slow reducing the impact noise of the armature abutting against the stopper.

Abstract: An apparatus and method for controlling a solenoid valve wherein the flow rate of the valve relative to a specific percent duty cycle may be varied. The controller is such that after the desired flow of the solenoid valve is determined, the frequency and percent duty cycle of an output signal controlling the solenoid valve is varied. Such a controller utilizes varying frequencies to provide multiple slope flow rates with a single passage solenoid valve.

Abstract: A solenoid operated remote resetting device with a protective solenoid activation circuit is disclosed. The device includes a housing for enclosing and protecting a solenoid with a movable plunger, a movable mechanical operator having an operator arm extending through an opening defined in the housing and a circuit board on which a solenoid activation circuit is mounted. The solenoid activation circuit includes circuitry for protecting the solenoid from overheating due to intentional or unintentional prolonged current flow in the solenoid.

Abstract: A solenoid driver circuit includes an input terminal for receiving a solenoid actuation pulse, an output terminal for connection to a terminal of a solenoid coil, a pull-in current adjustment terminal, and a hold-in current duty cycle adjustment terminal. A pull-in current duration circuit includes a first input coupled to the input terminal, an output producing a pull-in current duration pulse, and a second input coupled to the pull-in current adjustment terminal. A hold-in current duty cycle control circuit includes a first input coupled to receive a triangular waveform signal, a second input coupled to the hold-in current duty cycle adjustment terminal, and a third input coupled to the output of the pull-in current duration circuit. An output transistor includes a control electrode coupled to an output terminal of the hold-in current duty cycle control circuit, and a current carrying terminal coupled to the output terminal.

Abstract: A driver circuit is provided to control current flow through a solenoid coil of an electric liquid dispensing device including a valve element and a dispensing orifice. The driver circuit includes a bidirectional current source coupled to the solenoid coil for applying current in opposite directions through the coil. In a forward current direction, a magnetic attraction is created between the solenoid coil and the valve element to retract the valve element from the dispensing orifice. In a reverse current direction, a magnetic repulsion is created between the solenoid coil and the valving element to force the valving element toward the dispensing orifice. The magnetic flux generated in the solenoid coil by the forward current is calculated, and the reverse current is applied to substantially demagnetize the solenoid.

Abstract: A driver circuit having logic circuitry which controls the coil and assoced contacts of a four pole double throw relay. The four pole double throw relay is toggled such that a large latching current flows through a first of a pair of solenoid coils of the magnetic-latching solenoid, while a relatively small current flows in the second solenoid coil of the magnetic latching solenoid in an opposite direction. Toggling the relay's coil causes the latching current to now flow through the second solenoid coil of the valve, while the relatively small current flows in the first solenoid coil of the magnetic latching solenoid again in the opposite direction.

Abstract: An inexpensive and small-scale fuel injector control system having a number of fuel injector driving circuits smaller than the corresponding number of driven fuel injectors, in a cylinder injection type internal combustion engine having cylinders that are distanced by two strokes with respect to fuel injection timing and where no overlap occurs in the fuel injection timing. One of the ends of each of the coils of plural injectors, for the cylinders that are distanced from each other by two strokes in the fuel injection timing without overlapping each other, are simultaneously connected to an output terminal of a driving circuit, while the other ends of the coils are connected, respectively, to switching means that are turned on or off at energization/deenergization timings of coils of the fuel injectors.

Abstract: The present invention relates to a method and apparatus for control of current rise time during multiple fuel injection events. The invention utilizes a single boost voltage supply circuit, in which the boost capacitor is designed to store slightly more than twice the total energy required to pull-in a single fuel injector solenoid during the prescribed time. A reference waveform simulating the desired current rise time is compared to the actual boost voltage produced by the circuit. The boost voltage is modulated (switched on and off) in order to maintain the boost voltage within a predetermined window around the reference waveform. This modulation will compensate for any droop in boost voltage at the time of actuation, and will also compensate for two solenoids being actuated at the exact same time.

Abstract: A method for signalling an energizing coil of a solenoid-operated reciprocating plunger pump employed as a fuel injection device, in which the energizing coil is energized via a current control circuit pulsed at high-frequency by an energizing current and each pulse causes an impulse movement of an armature driven by the energizing coil, and the current control circuit controls the energizing current flowing through the energizing coil as a function of a current setpoint curve, each pulse of the current setpoint curve comprises a gradually rising leading edge resulting in a corresponding gradually rising leading edge of the pulse of the energizing current in the energizing coil, the current setpoint curve being controlled so that the energizing current does not change faster than the maximum change in current possible for the minimum voltage available at the energizing coil and limited due to mutual induction.

Abstract: Pulsed-energy controllers and methods of operation thereof for driving inductive loads such as the actuator coil or coils of electromechanical actuators. The controllers utilize an inductor through which an initial current is established through a first circuit. The inductor is then switched across the actuator coil or other inductive load in a second circuit and the first circuit is opened. The back EMF of the inductor, limited by a high voltage protective device, causes a rapid rise in the current through the actuator coil, the rise being much faster than could be achieved by merely coupling the supply voltage, as used to establish the current in the inductor, directly to the actuator coil. By proper selection of the controller circuit and its parameters, the initial rapid current rise may continue to a current higher than a steady state current, after which the current will decrease to or toward the lower steady state current until the current pulse is terminated. Various embodiments are disclosed.

Abstract: The circuit on which the present invention is based has a control circuit in which a switching element and a measurement resistor are connected in series with the contactor coil. A pickup current control circuit picks up the voltage at measurement resistor and controls the switching element after comparison with a reference voltage. By parallel connection of an additional shunt resistor with measurement resistor, a current approximately twenty to thirty times higher can be achieved during the pickup phase than the holding phase by setting only a single reference voltage. In the holding phase the parallel circuit is disabled so that only the measurement resistor is operative.

Abstract: An electromagnetic fuel injection valve for injecting fuel by opening/closing a fuel flow path, includes a valve seat, a valve element for opening/closing the fuel flow path formed between the valve seat and the valve element, and a drive unit having at least one coil for driving the valve element. The drive unit includes a first magnetomotive force generating device using the at least one coil and a second magnetomotive force generating device, the first magnetomotive force generating device and the second magnetomotive force generating device being composed so that the first magnetomotive force generating device generates and raises its magnetomotive force at a larger rate of change in time in comparison with the second magnetomotive force generating device. A valve open state is held by the second magnetomotive force generating device which uses a smaller current flow in comparison with the first magnetomotive force generating device.

Abstract: A method and apparatus for controlling a solenoid-operated valve element are provided. The valve element is movable between first and second end positions, and is urgable toward the first end position by magnetic attraction caused by activation of the solenoid and is normally urged toward the second end position. The method further enables detection of the time at which the valve element returns to the second end position from the first end position after deactivation of the solenoid.

Abstract: An apparatus for tripping a circuit breaker having a trip coil. A trip circuit is coupled at a first node to a first power supply and at a second node to the trip coil. The trip circuit comprises a switch for closing in response to a control signal, a coil coupled to the switch so that current is allowed to flow through the coil when the switch closes, relay contacts operatively coupled to the coil so that the relay contacts close when current flows through the coil, and a zener diode for providing a low impedance path after the relay contacts close and for applying a holding voltage across the coil sufficient to keep the relay contacts closed while current flows through the low impedance path.

Abstract: A method of operating a fuel injector comprises the steps of applying a test waveform to a solenoid coil of the injector to cause a response by an armature assembly and measuring the response of the armature assembly while the test waveform is applied to the solenoid coil. A control waveform for the injector is developed as a function of the variation of the measured response of the armature from a selected operational characteristic. The developed control waveform is thereafter applied to the solenoid coil to cause the armature assembly to approach a nominal position.

Abstract: A fuel injector control circuit and method include first switching circuitry (128, 134, 138, 142, 148, 152, 154) to selectively apply a first electrical signal (171) to a solenoid (114) to vary a load signal (176) between a first maximum (201) threshold and a first minimum (203) threshold. Second switching circuitry (130, 132, 136, 140, 148, 154) to selectively applies a second electrical signal (198) to the load (114) to vary the load signal (176) between a second maximum (205) threshold and a second minimum (207) threshold. The second electrical signal (198) has a magnitude substantially higher than the first electrical signal. Preferably, the second maximum threshold (205) has a magnitude less than a magnitude of the first maximum threshold (201), and greater than a magnitude of the first minimum threshold (203), and the second minimum threshold (207) has a magnitude less than the magnitude of the first minimum threshold (203).

Abstract: A control valve of an engine fuel system includes a valve member which is coupled to an armature and is moved to engage a seating when a winding is energized. The current flow in the winding is first allowed to rise to a peak value to initiate movement of the armature and valve member at which time the winding is disconnected from the supply. The decay of current in the winding is controlled using two rates of current decay to ensure that the valve member moves into engagement with the seating with the minimum of bounce.

Abstract: An improved power management circuit for regulating current on a loop converts a high voltage, low current loop circuit to a low voltage source for devices associated with the loop. Additionally, the improved power manager provides a port for frequency shift key (FSK) transmit and receive signals.

Abstract: A second operation mode without a hold period is used for starting up an engine when the ambient temperature is extremely low so that an electromagnetic coil remains fed with the current until the valve opening is completed, thus ensuring elimination of an injection valve cling up. A full opening of the injection valve is recognized by detecting a decrease of a coil current in the electromagnetic coil. The lower the temperature where the cling up is hardly eliminated in a short period, the longer the energizing period for the coil is provided. Consequently, such an event as failing to eliminate the cling up due to too short of the energizing period will be prevented.

Abstract: A method for controlling drive of an injector for an internal combustion engine which is capable of reducing a minimum injection quantity available for the control to increase a dynamic range of the injector is disclosed. A voltage across a solenoid coil is stepwise increased when a drive pulse is generated, so that a current fed to the solenoid coil is increased to a level higher than that of the drive current at the time when an injection valve starts port opening operation. Then, the drive current is gradually reduced toward a hold value required to hold the injection valve at a port opening position at a time-based variation ratio less than that of the drive current at the time when the voltage across the solenoid coil is stepwise decreased from a peak value, so that the voltage is stepwise reduced at the time when the drive pulse is extinguished, resulting in the drive current being extinguished.

Abstract: A control circuit for an electromagnetically operable fuel control valve of a vehicle engine includes a tank capacitor which upon closure of first and second controllable switches supplies current to the winding of the valve to achieve a high rate of rise of current in the winding and rapid operation of the valve. Following operation of the valve it is maintained in its operated state by current chopping action, the current rise being achieved by drawing current from a low voltage source through a third controllable switch. The current fall is at a high rate and the resultant high voltage induced in the winding is utilized to recharge the tank capacitor.

Abstract: A fuel injection injector controller comprises high voltage generation means for stepping up voltage based on electric power from a power supply to generate a voltage higher than the power supply, first switching means being disposed on a power supply passage from the high voltage generation means to an injector for conducting when a valve of the injector is opened upon reception of a drive signal, negative voltage generation means for generating a negative-polarity voltage, and second switching means being disposed on a power supply passage from the negative voltage generation means to the injector for conducting when the valve of the injector is closed upon reception of the drive signal.

Abstract: A fuel injector control system for a cylinder injection type internal combustion engine capable of suppressing a concentrative heat generation at a voltage generating circuit, which system includes a sensor means (1) for detecting operation state of the internal combustion engine to thereby output engine operation state information (D), a control parameter arithmetic means (2) for determining arithmetically a fuel supply quantity and a fuel injection timing for the engine on the basis of the engine operation state information (D), a plurality of cylinder injection type fuel injectors (61 to 66) for injecting fuel directly and individually to cylinders (#1 to #6) of the engine, a driving circuit (5) for driving electrically the fuel injectors (61 to 66) in response to control signals (C1, . . . , C6) outputted from the control parameter arithmetic means (2), and a voltage generating circuit (4) for supplying fuel injection signals (J1, . . . , J6) to the fuel injectors (61, . . .

Abstract: A device for controlling at least one electromagnetic load, which includes a first switching device arranged between a first terminal of a supply voltage and a first terminal of at least one load, and a second switching device arranged between a first terminal of an assigned load and the second terminal of the supply voltage. The energy released during the transition from a first higher current (IH) to a second lower current (IH) is stored in a storage device.

Abstract: A control system for an electronic device such as a solenoid for a vehicle transmission which is controlled by PWM. In the system, a difference (I.sub.H -I.sub.L) between the maximum value and the minimum value of current supplied to the solenoid is calculated and current supplied to the solenoid through a driver circuit is calculated based on the calculated difference and a predetermined coefficient as:I=I.sub.L +(I.sub.H -I.sub.L).times.Kduty.When a solenoid is controlled through PWM, feedback correction of the current flow becomes necessary owing to fluctuation in the voltage of the on-board power supply and fluctuation in the resistance of the electronic device with temperature. Since the instantaneous current in the solenoid varies constantly with the duty ratio, the detected value therefore differs depending on the sampling time point. Prior art smoothing solves the problem, but leads to raise the feedback high, causing overshooting.

Abstract: A method of energizing an electromagnetically operable valve which comprises a valve member movable into engagement with a seating when a winding is energized comprising connecting the winding to a DC supply to achieve a rapid rate of rise of current. The current is controlled at the peak value and is then reduced to a low value after an initial movement of the valve member. The valve member continues its movement towards the seating and the current is restored prior to engagement of the valve member with the seating to substantially eliminate bouncing of the valve member away from the seating.

Abstract: An electromagnetic force generated in a valve driving apparatus is rapidly decreased when a valve body moves to a position close to the end of its stroke so that a shock generated when the valve body reaches the end of the stroke is reduced. The valve body is movable between opposite ends of its stroke so as to open and close a valve provided in an internal combustion engine. An electromagnetic coil generates an electromagnetic force exerted on the valve body. A current supplied to the electromagnetic coil is controlled in accordance with an operational condition of the internal combustion engine. The current flowing in the electromagnetic coil is rapidly decreased when the valve body approaches the end of its stroke.

Abstract: First-order failure mode arrangement for driving an actuator coil for a switch element employs a microprocessor controller and a driver circuit that includes an amplifier switching device, such as a transistor, a capacitor that ac-couples the output of the microprocessor to a control electrode of the amplifier switching device, and the actuator coil which is tied between a voltage source and an output electrode of the amplifier switching device. The microprocessor also has a capability of interrogating the on or off condition of the switch element. The switch element can be, for example, the gas valve relay for a gas furnace. The switch element can be tested to ensure that it is capable of both closing and opening when directed, and to ensure that of the switch element is not locked or frozen into a closed condition.

Abstract: Contactor equipment with an operating magnet with an operating coil (CW) as well as an armature, which moves in dependence on the current through the operating coil. The contactor has control means (TR, CC, R1. R2, R3) which control the voltage supplied to the operating coil. During the closing operation of the contactor, for utilization of the current-reducing effect of the change of inductance taking place because of the movement of the armature during a closing operation, a voltage is supplied to the operating coil which is substantially constant during the closing operation and independent of the current of the operating coil. After a completed closing operation, the current is controlled through the operating coil in accordance with a reference value.

Abstract: The DC actuator control circuit with voltage compensation, current control and fast dropout period employs an electronic chopper incorporating an oscillator having a variable duty cycle controlled by sensing of coil current. Coil current is sampled through a series resistor by a feedback amplifier which increases or decreases the period in which the switch for the coil circuit remains on to sustain average coil current at the desired MMF. A threshold detector provides an initial triggering signal to initiate operation of the actuator and the control circuit responsive to a predetermined source voltage and a gate signal generator responds to the triggering signal with a time constant sufficient to drive the coil through a pickup interval. Inrush current is limited by the oscillator through sensing of coil current.

Abstract: A control circuit drives the coil of a contactor in response to a control voltage being applied. The control circuit includes a power supply that produces a regulated output voltage from the control voltage. The onset of the regulated output voltage starts a timer which controls the width of pulses produced by a PWM controller. The pulses control a transistor that applies the control voltage to the coil. Initially the pulses cause a high current to flow through the coil to close the contactor and after an interval of time the timer signals the PWM controller to shorten the pulses which applies lesser current to the coil to keep the contacts closed. A flyback circuit provides a relatively low reverse voltage drop path in parallel with the coil to maintain the electromagnetic field during the periods between the pulses. When the control voltage is removed to open the contactor, the flyback circuit provides a high reverse voltage drop path to promptly dampen the coil current.

Abstract: A method of operating an electromagnetic actuator having an electromagnet provided with a pole face, an armature movable towards and away from the pole face and a resetting spring exerting on the armature a resetting force urging the armature away from the pole face, includes the steps of supplying current to the electromagnet for generating an electromagnetic force moving the armature towards the pole face against the resetting force; and controlling the current supplying step such that at least along a terminal portion of the displacement path of the armature during its approach toward said pole face, the force/time curve of the magnetic force extends substantially parallel to and lies above the force/displacement spring curve of the resetting spring.

Abstract: A process and a device for controlling a movement of an armature of an electromagnetic switching element having an exciter coil. A first setpoint for the current can be defined after a first time. A second setpoint for the current can be defined after a second time. The second setpoint is smaller than the first setpoint. The second time also occurs before a third time at which the armature has reached its end position.

Abstract: A method of detecting a fault of an electromagnetically-actuated intake/exhaust valve is disclosed. A valve body is supported in neutral position by the energizing force of an elastic member, and the electromagnetic force generated by supplying a current to the coils arranged on the two sides of a plunger is applied to the plunger thereby to operate the valve. A fault is detected based on a change of the current flowing in one coil attracting and holding the plunger with the inductance change of the same coil when the plunger is switched from the position of the same coil to the position of the other coil. This method improves the fault detection accuracy for the electromagnetically-actuated intake/exhaust valve over the prior art.

Abstract: A solenoid driving apparatus includes at least two solenoids of which driving periods do not overlap, a driving unit for driving each solenoid, and a signal generating unit for giving the driving unit a control signal information of each solenoid. The driving unit includes circuit sections jointly used with regard to the driving of each solenoid, and drives each solenoid based on the control signal information corresponding to each solenoid. The signal generating unit generates the control signal information of each solenoid which is given to the driving unit based on the drive pulse signal corresponding to each solenoid. Also, while a control signal information is given to the driving unit based on the drive pulse signal corresponding to one solenoid, the signal generating unit does not accept the input of any drive pulse signal even when a drive pulse corresponding to the other solenoid is generated by a noise.

Abstract: The control device has a drive circuit, in turn having a number of modular circuits--one for each inductor--activated selectively and receiving timing signals, and a common circuit connected to the modular circuits and cooperating with the activated modular circuit to supply the respective inductor. Each modular circuit has a first controlled switch connected between a first input terminal and a respective first output terminal, and a second controlled switch connected between the respective first output terminal and a storage capacitor; and the common circuit has a third controlled switch connected between the storage capacitor and a respective second output terminal, and cooperating with the second controlled switch to selectively transfer energy between the storage capacitor and the respective inductor.

Abstract: A non-burnout controller for a switching coil is disclosed. The controller has a pulse timer, a relay switch, and an actuation switch. After being reset and actuated, the pulse timer defines a pulse having a predetermined pulse period. The relay switch has a switch actuation input for receiving the pulse and first and second switch outputs for being electrically coupled to first and second taps of the switching coil. The relay switch places a switching voltage across the outputs during the pulse period such that the switching coil has a switching current running therethrough. The relay switch places a substantially zero voltage across the outputs before and after the pulse period such that the switching coil has substantially no switching current running therethrough. The actuation switch has first and second positions. Upon being changed to the first position, the actuation switch resets the timer, whereby the switching coil has substantially no current running therethrough.

Abstract: .?.A circuit comprising a switch series connected to a load; a first and second current recirculating branch alternately connectable parallel to the load, for reducing the current in the same; and a logic control unit for opening and closing the switch and recirculating branches, so that the load is supplied with a current rising to a peak value and then falling rapidly to and oscillating about a lower hold value; a transistor being provided for reducing the voltage supplied to the load by the first recirculating branch at the end of the fast fall phase, so as to eliminate uncontrollable operating zones and prevent the load current from falling below the hold value..!..Iadd.A device for driving an inductive load such as a fuel injector includes a drive switch and a voltage regulator that are coupled to the inductive load. The device also includes a control circuit that is coupled to the voltage regulator, the drive switch, and the inductive load.