Abstract: A valve for controlling fluid flow, the valve comprising: a first plate comprising a plurality of first holes extending through said first plate; a second plate comprising a plurality of second holes extending through said second plate, the second holes being substantially offset from the first holes of said first plate; wherein said first plate and said second plate are arranged to form a cavity therebetween in fluid communication with the first holes of said first plate and the second holes of said second plate; and a flap disposed and moveable between said first plate and said second plate, said flap having holes substantially offset from the first holes of said first plate and substantially aligned with the second holes of said second plate; wherein said flap is operable to be motivated between said first and second plates in response to a change in direction of differential pressure of the fluid across the valve; wherein said first plate comprises a coating disposed on a surface of the first plate; where

Abstract: A method for controlling a microfluidic pump having a pump body defining a cavity, and an actuator arranged to generate pressure oscillations of a fluid contained within the cavity in order to cause fluid flow through an inlet and an outlet of the cavity, the method comprising: oscillating the actuator at a first frequency and determining an indication of a peak velocity of the a peak velocity of the actuator at said first frequency; oscillating the actuator at a second frequency and determining an indication of a peak velocity of the actuator at said second frequency; and adjusting the frequency of oscillation of the actuator to said first or second frequency for which the lowest peak velocity of the actuator was determined.

Abstract: A pump for a microfluidic device is disclosed. The pump comprises an actuator and a resilient isolator which is a planar, layered structure. The resilient isolator may comprise a support layer and optionally other layers for strengthening against tensile stress imposed by bending. Alternatively or in addition, the resilient isolator may comprise a plurality of annular regions, layers of the resilient isolator being configured such that at least one of the plurality of annular regions is less resistant than another one of the plurality of annular regions to bending. The actuator may comprise a piezoelectric disc including a surface which comprises electrode regions for electrical connection with respective conductive regions of a conductive layer of the resilient isolator, and an alignment feature for rotational alignment of the piezoelectric disc to ensure the electrical connection between the electrode regions and the respective conductive regions.

Abstract: A valve for controlling fluid flow, the valve comprising: a first plate comprising a plurality of first holes extending through said first plate; a second plate comprising a plurality of second holes extending through said second plate, the second holes being substantially offset from the first holes of said first plate; wherein said first plate and said second plate are arranged to form a cavity therebetween in fluid communication with the first holes of said first plate and the second holes of said second plate; and a flap disposed and moveable between said first plate and said second plate, said flap having holes substantially offset from the first holes of said first plate and substantially aligned with the second holes of said second plate; wherein said flap is operable to be motivated between said first and second plates in response to a change in direction of differential pressure of the fluid across the valve; wherein said first plate comprises a coating disposed on a surface of the first plate; where

Abstract: A method of making an actuator for a resonant acoustic pump comprises: forming a through-hole in a ceramic material of a piezoelectric layer of the actuator, prior to assembly of the piezoelectric layer with other layers of the actuator; forming a through-hole in a flexible circuit layer of the actuator; forming a through-hole in an end plate layer of the actuator; and disposing each of the piezoelectric layer and the end plate layer on a respective one of opposite sides of the flexible circuit layer, so that the through-holes align to provide a passageway for a fluid to pass through the actuator.

Abstract: A pump for a microfluidic device is disclosed. The pump comprises an actuator and a resilient isolator which is a planar, layered structure. The resilient isolator may comprise a support layer and optionally other layers for strengthening against tensile stress imposed by bending. Alternatively or in addition, the resilient isolator may comprise a plurality of annular regions, layers of the resilient isolator being configured such that at least one of the plurality of annular regions is less resistant than another one of the plurality of annular regions to bending. The actuator may comprise a piezoelectric disc including a surface which comprises electrode regions for electrical connection with respective conductive regions of a conductive layer of the resilient isolator, and an alignment feature for rotational alignment of the piezoelectric disc to ensure the electrical connection between the electrode regions and the respective conductive regions.

Abstract: A fluid pump includes a pump body having upper and lower parts, each comprising a substantially cylindrical side wall closed at one end by a substantially circular end wall and partially closed at the opposite end by an actuator disposed in a plane substantially parallel to and between the end walls. A single cavity is thereby formed having upper and lower portions. The cavity encloses the actuator and is bounded by the end walls and side walls of the pump body and the surfaces of the actuator. A substantially open actuator support structure connects the actuator to the pump body and enables free flow of fluid between the upper and lower cavity portions. At least two apertures are provided through the pump body walls, at least one of which is a valved aperture. All of the apertures located substantially at the centres of the end walls are valved apertures.

Abstract: A fluid pump comprising: a pump body having upper and lower parts, each comprising a substantially cylindrical side wall closed at one end by a substantially circular end wall and partially closed at the opposite end by an actuator disposed in a plane substantially parallel to and between the end walls, thereby forming a single cavity having upper and lower portions which encloses the actuator and is bounded by the end walls and side walls of the pump body and the surfaces of the actuator; a substantially open actuator support structure connecting the actuator to the pump body and enabling free flow of fluid between the upper and lower cavity portions; at least two apertures through the pump body walls, at least one of which is a valved aperture; wherein all apertures located substantially at the centres of the end walls are valved apertures; wherein, in use, the actuator oscillates in a direction substantially perpendicular to the plane of the end walls causing an acoustic wrapped standing wave to exist in t

Abstract: A valve for controlling the flow of fluid having first (16) and second (14) plates with offsetting apertures and a sidewall (12) disposed between the plates around the perimeter of the plates to form a cavity (15) in fluid communication with the apertures is disclosed. The valve further comprises a flap (17) disposed and moveable between the first and second plates and having apertures (22) substantially offset from the apertures (20) of one plate (16) and substantially aligned with the apertures (18) of the other plate (14). The flap is motivated between the two plates in response to a change in direction of the differential pressure of fluid across the valve.

Abstract: A pump having a substantially cylindrical shape and defining a cavity formed by a side wall closed at both ends by end walls wherein the cavity contains a fluid is disclosed. The pump further comprises an actuator operatively associated with at least one of the end walls to cause an oscillatory motion of the driven end wall to generate displacement oscillations of the driven end wall within the cavity. The pump further comprises an isolator operatively associated with a peripheral portion of the driven end wall to reduce dampening of the displacement oscillations. The pump further comprises a valve for controlling the flow of fluid through the valve. The valve has first and second plates with offsetting apertures and a sidewall disposed between the plates around the perimeter of the plates to form a cavity in fluid communication with the apertures.

Abstract: A valve for controlling the flow of fluid having first (16) and second (14) plates with offsetting apertures and a sidewall (12) disposed between the plates around the perimeter of the plates to form a cavity (15) in fluid communication with the apertures is disclosed. The valve further comprises a flap (17) disposed and moveable between the first and second plates and having apertures (22) substantially offset from the apertures (20) of one plate (16) and substantially aligned with the apertures (18) of the other plate (14). The flap is motivated between the two plates in response to a change in direction of the differential pressure of fluid across the valve.

Abstract: A pump having a substantially cylindrical shape and defining a cavity formed by a side wall closed at both ends by end walls wherein the cavity contains a fluid is disclosed. The pump further comprises an actuator operatively associated with at least one of the end walls to cause an oscillatory motion of the driven end wall to generate displacement oscillations of the driven end wall within the cavity. The pump further comprises an isolator operatively associated with a peripheral portion of the driven end wall to reduce dampening of the displacement oscillations. The pump further comprises a valve for controlling the flow of fluid through the valve. The valve has first and second plates with offsetting apertures and a sidewall disposed between the plates around the perimeter of the plates to form a cavity in fluid communication with the apertures.