A method for determining a switching state of a valve, an inductance variable being determined on the basis of current and voltage measurements and the switching state being determined on the basis of the inductance variable. Also disclosed is a solenoid valve assembly for carrying out such a method.

A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet that translates therein is provided. The drive circuit includes a supply bus, a return bus, a flyback circuit, and a switch. The supply bus is configured to couple the solenoid coil to a power supply and supply a coil current. The return bus is configured to provide a ground path for the coil current. The flyback circuit is coupled in parallel to only the solenoid coil. The flyback circuit includes only a bipolar diode. The switch is coupled in series with the solenoid coil and configured to couple and decouple the solenoid coil to the return bus.

A method for controlling a magnetic valve and particularly a method for dispensing and/or aspirating a volume of liquid as well as a corresponding dispenser/pipetting apparatus is disclosed. The method for controlling a magnetic valve has measuring a capacitance at the magnetic valve and determining a position of a plunger based on the measured capacitance. The method for dispensing or aspirating a volume of liquid has controlling a flow of a system fluid by a magnetic valve located between a pressure source and a dispenser/pipetting tip, dispensing or aspirating a volume of liquid through an exterior opening of the tip dependent on the flow of the system fluid, wherein controlling the flow and determining a flow time in dependence of the volume of liquid to be dispensed or aspirated, and controlling the magnetic valve is held open for the duration of the flow time.

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.

A method for controlling a part movable with a coil. In this case, a current flowing through the coil and/or a voltage applied to the coil is/are scanned in order to generate a coil signal. In a further step, at least one movement parameter representing an oscillatory movement of the part is ascertained by using the coil signal. Finally, at least one signal parameter of a dither signal is optionally changed to generate the oscillatory movement by comparing the movement parameter to the at least one setpoint value to adapt the oscillatory movement to the setpoint value.

According to an embodiment of the present invention, there is provided a method of diagnosing an abnormal state of a valve including: applying a current having a predetermined intensity to a valve; estimating a resistance value of the valve on the basis of an intensity of a feedback current from the valve according to the application of the current and a voltage between both terminals of the valve; and when a difference between a resistance value of the valve estimated at a first time point and a resistance value of the valve estimated at a second time point is greater than or equal to a threshold, determining that abnormality has occurred in the valve.

The present disclosure provides a coil driving device comprising: an input voltage sensing unit for sensing an input voltage; a switch unit configured to make a switching operation to supply a driving current to a coil; a PWM circuit unit for outputting a pulse width modulation (PWM) signal for the switching operation of the switch unit; an impedance adjustment unit for varying an impedance value such that the PWM signal is adjusted, thereby limiting the driving current; and a control unit for causing the impedance adjustment unit to vary the impedance value on the basis of the input voltage, thereby adjusting at least one of the duty ratio of the PWM signal and the frequency thereof.

A method is for operating a valve that includes a linearly movable control slide, at least one solenoid, and a position sensor. The linearly movable control slide is preloaded by at least one spring in a direction of a zero position. The at least one solenoid is coupled to the control slide in such a way that the control slide can be moved away from the zero position by application of current to the solenoid. The position sensor is configured to measure an actual instantaneous position of the control slide. Each solenoid is assigned a current control device configured to influence a current through the relevant solenoid based on an instantaneous current control variable. The instantaneous current control variable is dependent on a quasi-periodic dither current control variable. The method also includes calculating an actual dither amplitude from the actual instantaneous position using a band-pass filter.

A fluid dispensing device and method for controlling the device are provided. The device includes a housing defining a fluid outlet. A valve controls the flow of fluid to the outlet. A sensor is configured to detect an object outside of and proximate to the housing. A solenoid is configured to move the valve between an open position and a closed position. A controller is configured to receive the output signal of the sensor, determine a characteristic of noise in the output signal such as a level of noise, adjust at least one of a sampling rate of the output signal and an amount of filtering of the output signal responsive to the characteristic of noise in the output signal, and transmit a control signal to the solenoid responsive to the output signal.

An electromagnetic switching-valve position detection system includes: an electric current control circuit in which an electric current from a power supply is smoothed to be a direct current, and is turned into a pulse wave alternating current, the pulse wave alternating current being transmitted to the secondary side and outputted as a smoothed direct current; a carrier wave generator configured to superimpose a high frequency carrier wave for position detection on a signal wave of the electric current command; and a detecting unit configured to extract a carrier wave frequency component for the position detection from a voltage feedback signal of the solenoid, detect a voltage amplitude from the frequency component, and obtain an amplitude signal. The control unit has a position determining unit configured to determine a position of the valve spool, and a determination circuit configured to output a valve position signal based on the determination signal.