Provided is an electromagnetic valve capable of stabilizing an injection amount even when injection is performed while an intermediate member continues to be displaced after valve closing and returns to a closed valve standby state.

For that purpose, a valve body 303 opens or closes a flow path. A movable iron core 404 moves the valve body 303 in a valve opening direction using a magnetic attraction force. An intermediate member 414 forms a preliminary stroke gap (g1) between the movable iron core 404 and the valve body 303 in a closed valve state. A stopper portion 410c collides with the intermediate member 414 when the intermediate member 414 moves in a direction in which the preliminary stroke gap (g1) is reduced.

A fuel injection controller includes an increase control portion applying the boost voltage to the coil to increase a coil current to a first target value, and a constant current control portion applying a voltage to the coil to hold the coil current to a second target value. A threshold is an energization time period that is necessary to reach a boundary point between a seat throttle area of a property line and an injection-port throttle area of the property line from an energization start time point. An initial-current applied time period is from the energization start time point that the boost voltage starts to be applied to the coil to a time point that the coil current is decreased to the second target value. The increase control portion controls the coil current such that the initial-current applied time period is less than the threshold.

A fuel injection controller includes an increase control portion applying the boost voltage to the coil to increase a coil current to a first target value, and a constant current control portion applying a voltage to the coil to hold the coil current to a second target value. A threshold is an energization time period that is necessary to reach a boundary point between a seat throttle area of a property line and an injection-port throttle area of the property line from an energization start time point. An initial-current applied time period is from the energization start time point that the boost voltage starts to be applied to the coil to a time point that the coil current is decreased to the second target value. The increase control portion controls the coil current such that the initial-current applied time period is less than the threshold.

The invention relates to a method for simulating malfunctioning solenoid valves for an internal combustion engine by influencing an activation time and a deactivation time of the solenoid valve. A current with a specified modifiable current strength flows through the solenoid valve in order to achieve an opening and closing process. The closing process is forced after the current supplied to the solenoid valve is activated at the activation time, and the opening process is forced after the current supplied to the solenoid valve is deactivated at the deactivation time. The current is applied with a charging current strength prior to the activation time for the duration of a charging phase, and after the activation time, the current is increased to peak current strength and subsequently reduced to a holding current strength. Furthermore, after the deactivation time, the current strength is reduced to a deactivation current strength, and after a delay, the current strength (I) increases again as a result of induction. A variation of the value and/or duration of the current strength and/or an application of an additional magnetic force is used to simulate a premature activation, a delayed activation, a premature deactivation, and/or a delayed deactivation.

A solenoid actuator is described. The solenoid actuator comprises an armature, pole piece(s), electromagnet coil(s) arranged, in response to energisation, to cause travel of the armature between first and second positions along a direction of travel, permanent magnet(s) positioned and orientated for latching the armature in at least the first position when the armature is in the first position and spring(s) arranged to bias the armature. The solenoid actuator can be operated to provide partial lift.

A solenoid actuator is described. The solenoid actuator comprises an armature, pole piece(s), electromagnet coil(s) arranged, in response to energization, to cause travel of the armature between first and second positions along a direction of travel, permanent magnet(s) positioned and orientated for latching the armature in at least the first position when the armature is in the first position and spring(s) arranged to bias the armature. The solenoid actuator can be operated to provide partial lift.

A fluid injector has a longitudinal axis (L) and a valve needle (12), which is axially moveable and operable to prevent a fluid injection in a closing position and to permit the fluid injection in further positions. The fluid injector also has an armature (14) which is mechanically coupled to the valve needle (12). Furthermore, the fluid injector has a solenoid assembly (30) which has at least a first and second coil (34, 36) and which is operable to magnetically actuate the armature (14) via an electrical signal (V) applied to at least one predetermined assortment of the at least two coils (34, 36).

A fluid injector includes a valve body, a valve needle and axially moveable in the valve body between a closing position that prevents a fluid injection and further positions that permit the fluid injection, an armature coupled to the valve needle for displacing the valve needle away from the closing position, and a solenoid assembly including at least a first and second coil and operable to magnetically actuate the armature via an electrical signal. A method for operating the fluid injector includes applying the electrical signal to the first coil to generate a magnetic field to move the armature for displacing the valve needle away from the closing position, evaluating a voltage across terminals of the first coil, and controlling the second coil with a further electrical signal to saturate a magnetic field in a portion of the valve body between the armature and solenoid assembly during evaluating the voltage.

A fuel injection controller includes an increase control portion applying the boost voltage to the coil to increase a coil current to a first target value, and a constant current control portion applying a voltage to the coil to hold the coil current to a second target value. A threshold is an energization time period that is necessary to reach a boundary point between a seat throttle area of a property line and an injection-port throttle area of the property line from an energization start time point. An initial-current applied time period is from the energization start time point that the boost voltage starts to be applied to the coil to a time point that the coil current is decreased to the second target value. The increase control portion controls the coil current such that the initial-current applied time period is less than the threshold.