A pump for use with a tube, having a rotor having an axis of rotation and a plurality of rollers configured to define an orbital path about the axis of rotation, the orbital path defined by a radius, and a roller bed having a surface adapted to support the tube for peristaltic compression by one or more rollers, wherein the surface has a predetermined profile comprising a circular arc segment and at least one side segment, the arc segment having a first curvature defined by the radius, and the at least one side segment having a second curvature lesser than the first curvature.

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 power profile for each actuation of the solenoid. The power profile includes: an initial portion which increases at a first overall rate, an intermediate portion which increases at a second overall rate different than the first overall rate, and a final portion which decreases at a third overall rate.

A control unit includes a first connector configured to connect a proportional pressure regulator to a positive pressure supply and a second connector configured to connect the proportional pressure regulator to a negative pressure supply. The control unit further includes at least one sensor configured to detect an amount of air flow (volume per unit of time), positive or negative, within an air flow line connected to an output of the proportional pressure regulator, and a third connector configured to connect the air flow line to an air side of a diaphragm. Additionally, the control unit includes a controller programmed to control at least an opening and closing function of the proportional pressure regulator to attain a desired amount of air flow (volume per unit of time), positive or negative, within the air flow line.

A pump cassette is disclosed. The pump cassette includes a housing having at least one fluid inlet line and at least one fluid outlet line. The cassette also includes at least one reciprocating pressure displacement membrane pump within the housing. The pressure pump pumps a fluid from the fluid inlet line to the fluid outlet line. A hollow spike is also included on the housing as well as at least one metering pump. The metering pump is fluidly connected to the hollow spike on the housing and to a metering pump fluid line. The metering pump fluid line is fluidly connected to the fluid outlet line.

A pump cassette is disclosed. The pump cassette includes a housing having at least one fluid inlet line and at least one fluid outlet line. The cassette also includes at least one reciprocating pressure displacement membrane pump within the housing. The pressure pump pumps a fluid from the fluid inlet line to the fluid outlet line. A hollow spike is also included on the housing as well as at least one metering pump. The metering pump is fluidly connected to the hollow spike on the housing and to a metering pump fluid line. The metering pump fluid line is fluidly connected to the fluid outlet line.

Described is a method for manufacturing a diaphragm assembly through the use of injection molding. The method can avoid the use of PTFE as a chemically resistant coating. Further, the method can increase overall adherence of a polymer diaphragm to an insert through the use of an interference surface on at least the surface of a head of the insert.

There is provided a wobble plate piston water pump for use in a pressure washer and driven by a driving source, the water pump includes a pump body, a wobble plate, four or more pistons and a water passage defined by a water inlet and a water outlet. The driving source being electric powered and having a power consumption of less than or equal to a 15 ampere draw at 120 volts or 220 volts or the driving source being gas powered and having an engine displacement of less than or equal to 250 cubic centimetres.

A control unit includes a first connector configured to connect a proportional pressure regulator to a positive pressure supply and a second connector configured to connect the proportional pressure regulator to a negative pressure supply. The control unit further includes at least one sensor configured to detect an amount of air flow (volume per unit of time), positive or negative, within an air flow line connected to an output of the proportional pressure regulator, and a third connector configured to connect the air flow line to an air side of a diaphragm. Additionally, the control unit includes a controller programmed to control at least an opening and closing function of the proportional pressure regulator to attain a desired amount of air flow (volume per unit of time), positive or negative, within the air flow line.

A method of transporting a material includes at least one series of interconnected tube sections that can be opened or closed. At least one downstream tube section holds the material to be transported. A liquid jet is generated which accelerates the held material upstream out of at least the first downstream tube section into at least one opening upstream tube section which then holds a material part waiting for a next liquid jet to propagate that part to the next upstream tube section.

A breather assembly for a peristaltic pump comprises a breather tube and a cap connected to the breather tube. The cap comprises a sealing portion. One of the breather tube and the cap comprises a guide track and the other of the breather tube and the cap comprises a protrusion. The guide track comprises first and second sections separated by a first formation. The second section is bounded at its distal end by a second formation. The protrusion can pass the first formation when a first force is applied to the cap. The protrusion can pass the second formation when a second force is applied to the cap. When the protrusion is located within the first section, the sealing portion of the cap seals against the breather tube. When the protrusion is located within the second section, the sealing portion of the cap is spaced from the breather tube.