A drive circuit for operating a solenoid includes a main switch and a charge pump circuit. The main switch is coupled in series with a coil of the solenoid. The main switch is configured to selectively enable current flow from a voltage source according to a main switching signal to translate a poppet of the solenoid between an opened position and a closed position. The charge pump circuit is coupled to the voltage source. The charge pump circuit is configured to discharge through the coil to translate the poppet from the closed position to the opened position, and to charge when the poppet is held in the opened position.

A power converter module is connected to an electrical power supply and is configured to generate a first voltage and a second voltage for controlling operation of a valve, where the valve includes a solenoid for affecting opening and closing of the valve. The first voltage is a boost voltage for accelerating opening of the valve. The second voltage is a holding voltage for maintaining the valve in an open state. A boost control module is configured to control supply of the first voltage to the solenoid of the valve in accordance with a first state of an opening boost control signal when a valve control signal directs opening of the valve, and is configured to control supply of the second voltage to the solenoid of the valve in accordance with a second state of the opening boost control signal when the valve control signal directs opening of the valve.

A solenoid is latched in an energized position by a residual magnetic field established by a pulse of current. A degaussing current is selectively applied from a capacitor to unlatch the solenoid. Fail-safe return to the de-energized position occurs when the supply of power is lost.

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 system includes a latch circuit configured to monitor a switch and to operate an electronic latch based on a position of the switch. The system also includes a power supply circuit configured to provide a first voltage level to the latch circuit during normal operations and a second voltage level to the latch circuit during power loss. The power supply circuit includes a primary power circuit configured to provide the first voltage level to the latch circuit and a plurality of supercapacitors configured to be charged by the primary power circuit and provide the second voltage level to the latch circuit.

The present invention relates to an electromagnetic stopper for stopping and/or separating out cargo carriers and/or cargo conveyed on a continuously operated cargo conveyor system, comprising: a bistable solenoid having at least one coil and at least one permanent magnet; a cam, which can be retracted and extended with the aid of the solenoid, one or more electrical energy stores, in particular capacitors, a controller, which, with the aid of switches, discharges the energy store(s) via the at least one coil of the solenoid such that the cam is extended.

A method of controlling a solenoid valve having a solenoid coil and a poppet includes energizing a first node to a first voltage, and coupling the first node to the solenoid coil and energizing the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil to below an opening threshold. The method further includes energizing a second node to a second voltage with energy stored in the solenoid coil, and coupling the second node to the solenoid coil and energizing the solenoid coil using a DC signal configured to increase the current to above the opening threshold. The method further includes coupling the first node to the solenoid coil and energizing the solenoid coil using the PWM signal having a frequency and duty cycle configured to regulate the current to above a closing threshold.

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 first node, a second node, a control circuit, and a flyback circuit. The first node is configured to be energized by a power source to a first voltage. The control circuit is coupled to the first and second nodes, and is configured to: (1) selectively couple the first and second nodes in series with the solenoid coil, and periodically energize the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil. The flyback circuit is coupled to the solenoid coil and configured to energize the second node to a second voltage with energy stored in the solenoid coil.

A solenoid control circuit can make measurements during operation to determine the state of a solenoid and can provide for rapid re-energization of a solenoid upon detection of a dropout condition. A method of controlling a solenoid can include closing an input switch, cycling a low side switch based on voltage drop across a resistor, opening the input switch after a time interval, closing the low side switch and driving a discharge switch to control the discharge current rate from an energy storage device to an inductor. The method can include determining a condition of the inductor based on a time interval between actuation of comparators and maintaining a level of energy in the energy storage device sufficient to cause the inductor to produce a magnetic field for actuating a valve.

A method of controlling a solenoid valve having a solenoid coil and a poppet includes energizing a first node to a first voltage, and coupling the first node to the solenoid coil and energizing the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil to below an opening threshold. The method further includes energizing a second node to a second voltage with energy stored in the solenoid coil, and coupling the second node to the solenoid coil and energizing the solenoid coil using a DC signal configured to increase the current to above the opening threshold. The method further includes coupling the first node to the solenoid coil and energizing the solenoid coil using the PWM signal having a frequency and duty cycle configured to regulate the current to above a closing threshold.