A solenoid plunger movement detection system and method can include: detecting current supplied to a solenoid with a current sensor; converting the current supplied to the solenoid into a digital signal with a counter coupled to a first comparator; detecting a peak within the digital signal with a peak detector; comparing the peak to the digital signal with a second comparator coupled to the peak detector; measuring a dip from the peak and measuring a trough with the second comparator; generating a fault when the peak and the trough indicate a smooth current ramp to the solenoid; receiving configurable parameters for processing the digital signal with a signal processor; and providing configurable parameters to the counter, the second comparator, the signal processor, or a combination thereof with an interface.

The invention concerns a method for generating a pulsed magnetic field, the method being implemented using a device (10) comprising an electrical supply (20), a switch (25), a capacitor (15) and a coil (30) having a first extremity (80) connected to an electrical ground and a second extremity (85), the capacitor (15) comprising a first electrode connected to the electrical ground and a second electrode, the switch (25) being able to commute between a first configuration wherein the second electrode and the second extremity (85) are electrically insulated and at least one second configuration wherein the second electrode and the second extremity (85) are electrically connected, the capacitor (15), the switch (25) and the coil (30) forming a series circuit when the switch (25) is in the second configuration, the series circuit being underdamped.

There is a solenoid including a stator having a first stator tooth and a second stator tooth, and an armature having a first armature tooth and a second armature tooth. The armature is moveable with respect to the stator over a predetermined stroke. A coil is associated with one of the stator and the armature for conducting an electric current and generating magnetic flux that is guided by the stator and the armature. The stator or the armature acts as a ferromagnetic core for the coil. There is a first air-gap between the first stator tooth and the first armature tooth that has a first length, and a second air-gap between the second stator tooth and the second armature tooth that has a second length. The first and second lengths are constant to within a predetermined margin over the predetermined stroke when the first and second armature teeth overlap the first and second stator teeth respectively.

A rear electric brake ECU includes a delay element. More specifically, the delay element is disposed between an arithmetic element of the rear electric brake ECU and a first switching element (an FET) for driving a solenoid of a parking mechanism. The delay element delays a signal for driving this first switching element. Further, the rear electric brake ECU includes a diagnosis device for diagnosing the actuation state of the arithmetic element. The diagnosis device is set so as to be able to shut off power supply to the solenoid regardless of the state of a signal (a driving signal) of the solenoid if diagnosing that the actuation state of the arithmetic element is abnormal.

A diagnostic method for diagnosing a malfunction of a solenoid valve includes: a) storing reference features of a solenoid current waveform, b) detecting features of the solenoid current waveform during operation of the solenoid valve, c) comparing the reference features with the detected features, d) comparing the pressure value of fluid entering the solenoid valve inlet orifice with a predetermined range of pressure values in the event of deviation between the value of the detected features and the value of the reference features, e) adjusting the pressure value and repeating steps b) and c) in the case of deviation of the pressure value with respect to the pressure value range, and f) generating an alarm signal due to malfunction of the solenoid valve in the event of a deviation between the value of the detected features and the value of the reference and fluid pressure features within the pressure value range.

The invention relates to an electromagnetic positioning device (10) having energizable stationary coil means (1), a magnetic guide element (2) associated thereto and having a core section (2a) and an anchor unit (3) moveable in relation to the guide element (2) and along an axial movement direction (L) as a reaction to an energization of the coil means (1), wherein the guide element (2) is a hollow cylinder that partially surrounds the anchor unit (3). The positioning device (10) has an ultra-wide-band sensor unit (4) which is preferably integrated in the guide element (3) and is designed for measuring the position and/or the displacement of the anchor unit (3) in the guide element (2).

A method for controlling a vehicle seat valve, the piston thereof is actively displaced from a closed position into an open position or vice versa by an electrical voltage being applied to an electromagnetic drive means. The power of the drive means is regulated via an effective voltage which can be changed by means of pulse width modulation of an impulse voltage that has a constant frequency. In order to displace the piston from its closed position toward its open position, a duty cycle of the pulse width modulation is firstly increased from a rest duty cycle to a starting duty cycle of less than 100%, and the duty cycle is only raised to a final duty cycle when the piston has reached the open position and/or if a blockage impeding the displacement of the piston before it reaches its open position is identified.

Disclosed herein are reluctance actuators and methods for feedback control of their applied force. Embodiments of the reluctance actuators include an electromagnet positioned to deflect a metallic plate to provide a haptic output. The control of the force is provided without force sensors (sensorless control) by monitoring voltage and/or current (V/I) applied during an actuation. For a given intended force output, an electrical parameter value (flux, current, or other parameter) is read from a look up table (LUT). The LUT may store a present value of the inductance of the reluctance actuator. The feedback control may be a quasi-static control in which the LUT is updated after actuation based on the monitored V/I. The feedback control may be real-time, with a controller comparing an estimated electrical parameter value based on the measured V/I with the value from the LUT.

A dual-contact electro-permanent magnet (EPM) assembly of an information handling system may comprise a plurality of high-coercivity magnets situated on opposite ends of a low-coercivity magnet, a first EPM magnetic contact disposed between a first of the plurality of high-coercivity magnets and the low-coercivity magnet, and a second EPM magnetic contact disposed between a second of the plurality of high-coercivity magnets and the low-coercivity magnet. The low-coercivity magnet polarity may correlate to a direction of current pulse applied to an electrically conductive wire coiled around the low-coercivity magnet, and dependent upon the low-coercivity magnet polarity, the first EPM magnetic contact is capable of operating in an attractive magnetic state to attract a ferromagnetic contact of a peripheral device while the second EPM magnetic contact is magnetically neutral with respect to the ferromagnetic contact.

The invention relates to a device for controlling armature solenoid provided with a DC voltage source (14), at least one buffer capacitor (18), which is connected in parallel to the DC voltage source (14) and has a known capacitance (C), and a first switch (28), which is arranged between the DC voltage source (14) and the buffer capacitor (18). The exciter coil (16) and a second switch (30) arranged in series therewith are connected in parallel to the buffer capacitor (18). A control and evaluation unit (22), when the buffer capacitor (18) is charged, opens the first switch (28) and closes the second switch (30) in order to determine, on the basis of the measurement voltage (20), the frequency of the resonant circuit having the capacitance (C) of the buffer capacitor (18) and the inductance (L) of the armature solenoid (12). The inductance (L) of the armature solenoid (12) is determined on the basis of the frequency, and the air gap width (h) of the armature solenoid (12) is determined on the basis of the inductance. The PWM control signal with which the armature solenoid (12) is operable in order to generate a predefined force to be applied by the armature solenoid (12) is applied to the second switch (30) on the basis of a look-up table or a mathematical modelling of the electromagnetic behavior of the armature solenoid (12).