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.

When a pipe pressure of a common discharge pipe during an independent discharge step in which only one reciprocating pump among a plurality of reciprocating pumps discharges a fluid to the common discharge pipe differs from internal pressures in pump chambers of the respective reciprocating pumps at discharge step start point angles, a stroke adjustment mechanism adjusts, on the basis of a pressure difference ΔP therebetween, effective stroke lengths of cross heads connected to plungers of the predetermined reciprocating pumps so that the internal pressures in the pump chambers reach the pipe pressure at the discharge step start point angles.

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 that dispenses measured liquids in a consistent proportional amount includes a plurality of cylinders, a plunger associated with each cylinder and a lever operatively connected to each plunger. Each of the cylinders is connected to a container having a chemical by an input tube. Each cylinder is also connected to a single outlet tube via a plurality of outlet tubes. The cylinders are sized and positioned to dispense a consistent proportional mixture regardless of the length of stroke of the handle.

What is suggested is a micromembrane pumping device for pumping a fluid, having: a pump chamber to which an inlet valve, an outlet valve, and a membrane device for varying a volume of the pump chamber are associated, wherein the membrane device has a plate-shaped actuator for deforming the membrane device; and influencing means for influencing the plate-shaped actuator and the volume of the pump chamber; wherein the membrane device has a plate-shaped membrane body limiting the pump chamber; wherein the plate-shaped actuator is arranged on a side of the plate-shaped membrane body facing away from the pump chamber; wherein the plate-shaped actuator is mounted to and electrically insulated from the plate-shaped membrane body by an electrically insulating glue layer; wherein at least one embedded portion of a support body at or in which a deformation sensor for detecting a deformation of the membrane device is arranged, is arranged within the glue layer to detect the volume of the pump chamber; wherein the influencing means, the plate-shaped actuator and the deformation sensor form a closed-loop control circuit for regulating a volume flow.

A diaphragm pump may comprise a housing defining a first pumping chamber, a second pumping chamber, and a hydraulic fluid chamber, a first flexible diaphragm separating the first pumping chamber from the hydraulic fluid chamber, a second flexible diaphragm separating the second pumping chamber from the hydraulic fluid chamber, a rod mechanically linking the first flexible diaphragm and the second flexible diaphragm such that an expansion of one of the first and second flexible diaphragms exerts a contraction force on the other of the first and second flexible diaphragms, and a piston disposed within the hydraulic fluid chamber and configured to reciprocate to cause a hydraulic fluid contained within the hydraulic fluid chamber to alternately exert an expansion force on the first and second flexible diaphragms.

A method of operating a pump can include advancing a stepper motor one or more additional steps in a first direction after detecting a first change in a limit sensor state corresponding to a piston reaching an end of its travel in a first direction. After advancing the stepper motor the additional step or steps in the first direction, the stepper motor can be reversed and advanced in a second direction until a second change in the limit sensor state is detected. The stepper motor can then be advanced in the second direction a predetermined number of steps associated with a full travel of the piston.

A control method and system for a resonant linear compressor applied for controlling the capacity of a cooling system. The method includes: a) reading a reference operation power (P.sub.ref) of the motor of the compressor; b) measuring an operation current (i.sub.MED); c) measuring an operation voltage of a control module of the compressor; d) calculating an input power (P.sub.MED) of the motor as a function of the operation current (i.sub.MED) and of the operation voltage; e) comparing the input power (P.sub.MED) with the reference operation power (P.sub.ref); f) if the reference operation power (P.sub.ref) is higher than the input power (P.sub.MED), then increase an operation voltage of the compressor (UC); g) if the reference operation power (P.sub.ref) is lower than the input power (P.sub.MED), then decrease the operation voltage of the compressor (UC).

The present invention concerns a method of controlling a liquid volume which can be conveyed with a metering pump in a given time, comprising the steps: a. providing an input signal for controlling the liquid volume which can be conveyed with the metering pump in the given time, and b.lLinking the input signal to an actuating signal which influences the liquid volume which can be conveyed with the metering pump in the given time so that a change in the input signal leads to a change in the actuating signal and thus a change in the liquid volume which can be conveyed. To react to individual process demands it is proposed according to the invention that linking in step b. is effected in such a way that a change in the input signal leads to a change in the liquid volume which can be conveyed with the metering pump in the given time, which change in the liquid volume is non-proportional to the change in the input signal.

A method operates a construction material and/or viscous-material pump having: at least one conveying cylinder, the conveying cylinder being designed to receive and discharge construction material and/or viscous material; and at least one conveying piston, the conveying piston being disposed in the conveying cylinder for movement in order to draw construction material and/or viscous material into the conveying cylinder and to displace drawn-in construction material and/or viscous material out of the conveying cylinder. The method includes: conveying construction material and/or viscous material, by movement of the conveying piston in order to draw in and displace construction material and/or viscous material; sensing a position variable during the movement, the position variable characterizing a position of the conveying piston along its stroke in the conveying cylinder; sensing a conveying variable during the movement, the conveying variable being of a different type than the position variable and characterizing the conveying of construction material and/or viscous material by the pump; and determining a profile of a subsequent movement of the conveying piston by linking the sensed position variable and the sensed conveying variable to each other; and controlling the subsequent movement in accordance with the determined profile.