A pump arrangement for powering a pump in providing a controlled volume of water to a drip nozzle in a drip-feed humidifier. The pump arrangement includes: a pump having a solenoid; a processing unit; and a power supply electrically connected to the solenoid via a switch which is controlled by the processing unit. The power supply is structured to supply power to the solenoid via the switch. The processing unit is programmed to modulate the power provided to the solenoid via the switch such that the power is supplied to the solenoid according to a mirror image power profile for each actuation of the solenoid for retracting the armature. The mirror image power profile includes: an initial portion which decreases at a third overall rate, an intermediate portion which decreases at a second overall rate different than the third overall rate, and a final portion which increases at a first overall rate.

A pump arrangement for powering a pump in providing a controlled volume of water to a drip nozzle in a drip-feed humidifier. The pump arrangement includes: a pump having a solenoid; a processing unit; and a power supply electrically connected to the solenoid via a switch which is controlled by the processing unit. The power supply is structured to supply power to the solenoid via the switch. The processing unit is programmed to modulate the power provided to the solenoid via the switch such that the power is supplied to the solenoid according to a mirror image power profile for each actuation of the solenoid for retracting the armature. The mirror image power profile includes: an initial portion which decreases at a third overall rate, an intermediate portion which decreases at a second overall rate different than the third overall rate, and a final portion which increases at a first overall rate.

A linear electro-mechanical system comprising: a stator including at least first and second stator electronic circuits or groups of circuits; a free piston mover movable in a reciprocating motion relative to the stator, the free piston including: a piston surface; a translator configured so that an electromagnetic force may be applied on the free piston mover by one or more of the stator electronic circuits or groups of circuits; and one or more translator electronic circuits, the system further comprising a switching device for each of the first and second stator electronic circuits or groups of circuits such that the current in each of the first and second stator electronic circuits or groups of circuits is independently controllable, and wherein at least one of the translator electronic circuits is configured to receive power from at least one of the independently controlled stator electronic circuits or groups of circuits during at least part of the stroke of the free piston mover.

An oscillating piston pump including: a first hollow tubular body in which a piston moves; a second hollow tubular body extending around the first hollow tubular body, carrying a solenoid that controls the movement of the piston, the first tubular body and the second tubular body forming a one-piece structural element.

The pump has a casing accommodating a piston and a driving part. The casing has a first casing member having a driving part retaining portion retaining the driving part, a second casing member fixedly stacked on the first casing member in the reciprocating direction of the piston, and a cylindrical pump chamber peripheral wall member disposed around a head of the piston. The second casing member has an end wall portion extending in a transverse direction substantially perpendicular to the reciprocating direction. A pump chamber, a delivery chamber, and a buffer chamber are defined between the first casing member and the end wall portion of the second casing member. The pump chamber, the delivery chamber, and the buffer chamber are disposed side-by-side in the transverse direction.

A mass shifting mechanism between twin equilibrium points comprises a movable slider between two equilibrium positions and actuating means active on the slider to bring it and keep it in a first and a second stationary spatial configuration through an action of electromagnetic field, the second stationary spatial configuration being different from the first stationary spatial configuration.

A mass shifting mechanism between twin equilibrium points comprises a movable slider between two equilibrium positions and actuating means active on the slider to bring it and keep it in a first and a second stationary spatial configuration through an action of electromagnetic field, the second stationary spatial configuration being different from the first stationary spatial configuration.

A system for monitoring flow conditions of fluid flowing from a product container through a solenoid pump. The system includes at least one solenoid pump comprising a solenoid coil, which, when energized, produces a stroke of the solenoid pump, at least one product container connected to the at least one solenoid pump wherein the at least one solenoid pump pumps fluid from the at least one product container during each stroke, at least one PWM controller configured to energize the at least one solenoid pump, at least one current sensor for sensing the current flow through the solenoid coil and producing an output of the sensed current flow, and a control logic subsystem for controlling the flow of fluids through the solenoid pump by commanding the PWM controller and for monitoring the current through the solenoid pump by receiving the output from the current sensor, wherein the control logic subsystem uses the measured current flow through the solenoid coil to determine whether the stroke of the solenoid pump is functional.

A system for monitoring flow conditions of fluid flowing from a product container through a solenoid pump. The system includes at least one solenoid pump comprising a solenoid coil, which, when energized, produces a stroke of the solenoid pump, at least one product container connected to the at least one solenoid pump wherein the at least one solenoid pump pumps fluid from the at least one product container during each stroke, at least one PWM controller configured to energize the at least one solenoid pump, at least one current sensor for sensing the current flow through the solenoid coil and producing an output of the sensed current flow, and a control logic subsystem for controlling the flow of fluids through the solenoid pump by commanding the PWM controller and for monitoring the current through the solenoid pump by receiving the output from the current sensor, wherein the control logic subsystem uses the measured current flow through the solenoid coil to determine whether the stroke of the solenoid pump is functional.

A linear motor compressor including a compressor housing and a cylinder housing having a plurality of opposing compression chambers. A piston freely reciprocates within the cylinder housing using a linear electric motor. A piston position feedback control system provides adaptive current output as a function of position feedback and/or velocity feedback from the piston and/or the electric motor, to directly power and control the electric motor, wherein the piston reciprocates without assistance from a mechanical spring or other equivalent centering force.