A fluid dispenser with a fluid pump for dispensing fluid on movement of an actuator, and an air pump for delivering a stream of air through at least one sound generator on movement of the actuator. The sound generator produces at least two sounds as the actuator is moved from a first position to a second position, with each sound produced in a different time period during a cycle of operation, or differing from the other sound in respect of one or more detectable sound characteristics, such as duration, frequency, temporal alignment, amplitude, and/or timbre. The time period of each sound is a function of the relative location of the actuator between the first and second positions.

A pump includes a cylinder, a piston and a controller. The cylinder has first and second ends and includes first and second inlet-outlet ports, each of the first and second inlet-outlet ports is configured to alternately intake a fluid to the cylinder and output the fluid from the cylinder. The piston is configured to be moved within the cylinder between the first and second ends by alternately reversing a direction of movement of the piston, so as to pump the fluid through the first and second inlet-outlet ports. The controller is configured to control the movement of the piston within the cylinder, including: (a) choosing between first and second operational modes, (b) in the first operational mode, controlling the piston to oscillate over a predefined interval that does not exceed a predefined distance from the first end or from the second end, and (c) in the second operational mode, controlling the piston to move at a selected speed between the first end and the second end.

A displacement control valve improved in the function of discharging a liquid refrigerant in a control chamber at startup achieves a reduction in startup time and an improvement in operating efficiency during control of a variable displacement compressor simultaneously. An opening area between a third valve section and a third valve seat surface in a control area to control the flow rate or pressure in a working control chamber is set smaller than an area of an auxiliary communicating passage, thereby reducing the minimum area of a Pc-Ps flow path in the control area.

The performance of a solenoid drive liquid pump can be very dependent on the magnitude and stability of an input voltage, with non-ideal input power resulting in loss of efficiency and potential damage to the pump. Pulse width of drive signals provided to the pump, which cause solenoids to alternately energize to move liquid through the pump, may be adjusted in duration in order to compensate for non-ideal input voltage. A drive control module of the pump gathers voltage information, determines an improved pulse width based upon that voltage information, and then provides drive signals based upon the improved pulse width. Operating in this manner, a pump can operate at or near peak efficiency despite both significant variances in input voltage and non-sinusoidal input voltage, and without customized components or adapters.

Metering pumps are typically used to move a specified volume of liquid in a specified time to provide an accurate flow rate. A recurring automatic priming function is provided for operating such a metering pump by running the pump for a short duration and periodically thereafter. This may maintain fluid in the pumping system such that the pump is automatically in a primed configuration.

A method for operating a linear compressor includes substituting a first observed velocity, a bounded integral of the first observed velocity, an estimated clearance, an estimated discharge pressure, and an estimated suction pressure into the mechanical dynamic model for the motor, calculating an observed acceleration for the piston with the mechanical dynamic model for the motor, calculating a second observed velocity for the piston by integrating the observed acceleration for the piston, calculating an observed position of the piston by integrating the second observed velocity for the piston, and updating an estimated clearance, an estimated discharge pressure, and an estimated suction pressure based upon an error between the first and second observed velocities and an error between the bounded integral of the first observed velocity and the observed position.

A fuel supply device includes: a linear actuator; a reciprocating pump having a boosting piston driven by the linear actuator and configured to reciprocate in an axial direction, the reciprocating pump being configured to suck the fuel when the boosting piston moves in a first direction and configured to boost and eject the fuel when the boosting piston moves in a second direction; and a controller configured to control driving of the linear actuator so as to adjust an amount of the fuel ejected from a boosting cylinder per reciprocating time by adjusting a ratio of a fuel ejection time and a fuel suction time of the reciprocating pump without changing the reciprocating time of the boosting piston in accordance with a load of the internal combustion engine. The adjustment adjusts a stroke length of the boosting piston and a moving speed of the boosting piston in the second direction.

Disclosed is a portable pump including a reciprocating air compressor arrangement with a crank driving a connecting rod and a piston within a cylinder, the connecting rod being connected to the crank and piston, the crank actuating the piston in a reciprocating motion within and relative to the cylinder, an electric motor having a drive shaft mounted to the crank and rotatable about a drive shaft axis, the drive shaft axis being at least substantially coaxially aligned with an axis of rotation of the crank, a control unit communicating with the electric motor to control the pump, a power supply communicating with the control unit to power the control unit and electric motor, a common housing containing the electric motor, reciprocating air compressor arrangement, control unit, and power supply, and an outlet fluidly connected to the reciprocating air compressor arrangement for fluidly engaging with an pumpable object.

A method of controlling a Free Piston Mover, the method comprising the steps of: generating a Control Parameter Set for closed loop control of a Target Control Variable, this set comprising a Target Control Variable Function together with one or more of: a Stroke Threshold Function; a Feed Forward Current Function; a Feedback Terms Function; Control Parameter Set Transition Conditions; transmitting the Control Parameter Set to an In-Stroke Controller in advance of the start of a Stroke to be controlled; modifying one or more of the constituents of the Control Parameter Set for any Future Stroke of the Free Piston Mover using a Future-Stroke Controller; and transmitting the modified Control Parameter Set to the In-Stroke Controller for the control of any Future Stroke.

Illustrative embodiments of diaphragm pumps having an automatic priming function, as well as related systems and methods, are disclosed. In one illustrative embodiment, a method of priming a diaphragm pump includes sensing, with a pressure sensor disposed at a fluid outlet of the diaphragm pump, a pressure of a fluid being pumped by the diaphragm pump, transmitting a pressure signal associated with the sensed pressure from the pressure sensor to a controller of the diaphragm pump, and identifying, on the controller, whether the diaphragm pump is primed by determining whether a characteristic of the pressure signal has reached a threshold.