Abstract: A method and apparatus for local infusion of a variety of biological response modifiers (BRMs) and chemotherapeutic agents including tumor necrosis factors (TNF) is described. In one embodiment, the device contains a synthetic pouch compartmentalized into three or more chambers, and an electronic apparatus controlling and modulating the delivery of the agents to the site of the tumor, so as to achieve a desired regimen in support of the elimination of a tumor burden. In one embodiment, an electronic system provides tailored and controlled regulation of the administration of such agents, using sensors to monitor the progress of the treatment. Desired dosing and scheduling of anti-tumor agents in a local setting is provided. In one embodiment, active control and regulation of the administration of medicating agents is attached to a synthetic pouch and with the aid of a piezoelectric valve and pump actuating mechanism. The apparatus provides the desired dose, duration and timing of dose delivery.

Abstract: A compact, high capacity pump for pumping fluid. A first one-way valve is between an inlet port and the pump's fluid chamber. A second one-way valve is between the pump's fluid chamber and an outlet port. A diaphragm separates a piezoelectric stack from the fluid chamber. A power source provides power to the piezoelectric stack causing it to expand and contract. The expansion and contraction of the piezoelectric stack causes fluid to be pumped from the inlet port to the fluid chamber through the first one-way valve and causes fluid to be pumped from the fluid chamber to the outlet port through the second one-way valve. In one preferred embodiment, both one-way valves are disc valves. In another preferred embodiment both one-way valves are MEMS valves.

Abstract: A piezoelectric pump includes a diaphragm that defines a pump chamber between the diaphragm and a pump body, and a piezoelectric element bonded to a surface of the diaphragm. The piezoelectric element is a bimorph piezoelectric element in which a plurality of piezoelectric layers are stacked, including a neutral layer disposed in the approximate middle of the piezoelectric element in the thickness direction and that is not displaced. The piezoelectric element can be efficiently displaced because a neutral plane of the diaphragm and the piezoelectric element bonded therein is located in the neutral layer.

Abstract: A method and apparatus for local infusion of a variety of biological response modifiers (BRMs) and chemotherapeutic agents including tumor necrosis factors (TNF) is described. In one embodiment, the device contains a synthetic pouch compartmentalized into three or more chambers, and an electronic apparatus controlling and modulating the delivery of the agents to the site of the tumor, so as to achieve a desired regimen in support of the elimination of a tumor burden. In one embodiment, an electronic system provides tailored and controlled regulation of the administration of such agents, using sensors to monitor the progress of the treatment. Desired dosing and scheduling of anti-tumor agents in a local setting is provided. In one embodiment, active control and regulation of the administration of medicating agents is attached to a synthetic pouch and with the aid of a piezoelectric valve and pump actuating mechanism. The apparatus provides the desired dose, duration and timing of dose delivery.

Abstract: In a liquid discharge control apparatus which uses a piezoelectric type diaphragm pump, an accumulator having a liquid accumulation cavity and a movable member is communicated to an outlet of the diaphragm pump. In discharge operation of the diaphragm pump, a quantity of the liquid in the liquid accumulation cavity is rapidly increased, and the movable member is elastically deformed so as to increase of the volume of the liquid accumulation cavity. Alternatively, in suction operation, when a back stream of the liquid occurs, the quantity of the liquid in a path communicated to the outlet of the diaphragm pump is decreased due to the back stream. The decrease of the liquid can be compensated by the decrease of the volume of the liquid accumulation cavity of the accumulator. Thereby, variation of the quantity of the liquid discharged from the outlet of the accumulator is reduced and the liquid can be discharged, smoothly.

Abstract: A method and apparatus for local infusion of a variety of biological response modifiers (BRMs) and chemotherapeutic agents including tumor necrosis factors (TNF) is described. In one embodiment, the device contains a synthetic pouch compartmentalized into three or more chambers, and an electronic apparatus controlling and modulating the delivery of the agents to the site of the tumor, so as to achieve a desired regimen in support of the elimination of a tumor burden. In one embodiment, an electronic system provides tailored and controlled regulation of the administration of such agents, using sensors to monitor the progress of the treatment. Desired dosing and scheduling of anti-tumor agents in a local setting is provided In one embodiment, active control and regulation of the administration of medicating agents is attached to a synthetic pouch and with the aid of a piezoelectric valve and pump actuating mechanism. The apparatus provides the desired dose, duration and timing of dose delivery.

Abstract: A micropump device including a first wafer and a second wafer attached to the first wafer. The first and second wafers are configured to define a chamber therebetween having a predetermined volume. A third wafer is attached to the second wafer to define an inlet section and an outlet section in fluid communication with the chamber. At least one of the second and third wafers are formed to define a moveable diaphragm configured to change the predetermined volume of the chamber for pumping a fluid between the inlet section and the outlet section.

Abstract: In some embodiments, piezoelectric air jet augmented cooling for electronic devices is presented. In this regard, an apparatus is introduced having a plurality of more than about one hundred lead-free piezoelectric layers and electrodes stacked on top of each other and formed around a central opening, and a diaphragm coupled to the piezoelectric layers and substantially covering the central opening to vibrate and blow air when an operating voltage is applied to the electrodes. Other embodiments are also disclosed and claimed.

Abstract: Disclosed is a piezoelectric pump. The piezoelectric pump includes a pump body, a drive unit, a detection section, and a control unit. The pump body includes a hole for introducing a fluid from outside thereinto and jetting the fluid from inside, a wall portion disposed so as to face the hole, and a piezoelectric body provided on the wall portion to vibrate the wall portion. The drive unit drives the piezoelectric body. The detection section detects a signal corresponding to a discharge rate of the fluid from the hole. The control unit controls a drive voltage and a drive frequency of the drive unit on the basis of the signal.

Abstract: A diaphragm air pump comprises a pump chamber, a diaphragm and one or more piezoelectric beams or bimorphs. Fluid flows into the pump chamber and then flows out of it, the diaphragm is provided within the pump chamber, and one or more central openings are formed in the diaphragm. One or more central check valves are provided in the central openings. The diaphragm is just bonded with piezoelectric beams, not fixed to the lower housing of the pump chamber in order to get large displacement. With the provided diaphragm air pump, it is possible to actively adjust the air quantity according to the requirement for fuel cell or a part-to-be-cooled, and it is also possible to reduce noise and power consumption compared with a conventional fan type cooler or air pumps.

Abstract: A gas flow generator comprising: an ultrasonic driver comprising a piezoelectric or electrostrictive transducer mounted on a substrate, operation of the transducer being arranged to cause the driver to bend; a first membrane disposed on or formed integrally with the transducer or the substrate; and a second membrane mounted substantially parallel with the driver and spaced a given distance therefrom, one of the membranes being perforate, whereby ultrasonic bending of the driver on actuation of the transducer causes a gas flow through the perforate membrane.

Abstract: A piezoelectric fan includes a piezoelectric actuator patch (110, 210, 310) and a blade (120, 220, 320) attached to the piezoelectric actuator patch. The blade has a hole (121, 127, 221) in it, and a door (122, 128, 222) is adjacent to the hole and attached to the blade (as with a hinge (123, 129, 223)) such that the door is capable of opening and closing.

Abstract: A variable displacement piezo-electric pump which includes a pump housing having a side housing wall defining a pump chamber, an inlet line and an outlet line communicating with the pump chamber, a flexible pump diaphragm spanning the side housing wall in the pump chamber, a diaphragm-stroking mechanism such as a piezo-electric stack engaging the pump diaphragm and a diaphragm support provided between the diaphragm-stroking mechanism and the side housing wall of the pump housing.

Abstract: A piezoelectric pump having a first opening in a center portion of a pump body, and a second opening apart from the center. An outer peripheral portion of a metal diaphragm is fixed to the pump body, and a piezoelectric element having a size that covers the first opening and does not cover the second opening is bonded to a back center portion of the diaphragm. By applying a voltage near the resonance frequency to the piezoelectric element, a portion of the diaphragm opposing the first opening and a portion of the diaphragm opposing the second opening are bent in opposite directions so that fluid is drawn in from one of the first opening and the second opening and is discharged from the other opening. Such a piezoelectric pump can increase the discharging pressure, and can reliably discharge the fluid even under a condition where the pressure on the discharging side is high.

Abstract: A piezoelectric pump capable of generating a large displacement at a central portion of a piezoelectric element even when a driving voltage is relatively low and preventing short-circuits caused by migration. The piezoelectric pump includes a pump body with a pump chamber, and a piezoelectric element that closes the pump chamber. The central area and the peripheral area of the piezoelectric element are bent in opposite directions by applying voltages to the piezoelectric element so that the volume of the pump chamber is changed. The piezoelectric element is a laminate including a plurality of piezoelectric layers with electrodes interposed therebetween. The central area and the peripheral area of each piezoelectric layer are polarized opposite to each other in the thickness direction, and the electrodes are formed such that voltages in the same direction in the thickness direction are applied to the central area and the peripheral area of each piezoelectric layer.

Abstract: The present invention in various embodiments relates to a variety of different types of fluidic adaptive lens systems, pumping systems for implementation in such lens systems, other systems employing such lens systems, and related methods of fabrication. In at least some embodiments, the present invention relates to a lens system that includes a reservoir having at least one flexible wall, a first actuator coupled in relation to the reservoir, and a terminal at which is located at least one of an integrated fluidic lens and a port configured to be coupled to an external fluidic lens. The terminal is coupled to at least one of the reservoir and the actuator, and at least one of the actuator and a first pumping system including the actuator is capable of causing fluid to be moved at least one of from the reservoir toward the terminal, and from the terminal toward the reservoir.

Abstract: A liquid cartridge includes: a container section that stores liquid; a plate-like vibration body that is submerged in the liquid and flows the liquid; and a driver section that drives the vibration body in a thickness direction, wherein the vibration body has an end section, and at least a portion of the end section of the vibration body in an in-plane direction continuously becomes thinner toward an end of the vibration body.

Abstract: An asymmetric micro pump may be adapted to provide a greater fluid compression between input and output ports of the micro pump, as well as increased flow rate due to higher actuation frequency. In some instances, asymmetric dual diaphragm micro pumps may be combined into assemblies to provide increased pressure build, improved pumping volume, or both, as desired.

Abstract: A controlled odor generator, comprising a central processing unit, at least one micropump unit, a sensor unit and a fan. The micropump unit is housed in a casing containing odorous fluid and has a micropump array for ejecting the odorous fluid in tiny droplets. The central processing unit regulates operation of the micropump unit, allowing to control timing quantity and mixture of spread odor. The sensor unit provides the central processing unit with environmental data, like temperature, air density and humidity, as well as human body states for controlling the micropump unit. Environmental changes are followed by a change of spraying of odor, and varying taste and demand are adapted to.

Abstract: A fluid pump comprising one or more actuators, two end walls, a side wall; a cavity which, in use, contains fluid, the cavity having a substantially cylindrical shape bounded by the end walls and the side walls, at least two apertures through the cavity walls, at least one of which is a valved aperture, wherein the cavity radius, a, and height, h, satisfy the following inequalities: a/h is greater than 1.2; and h2/a is greater than 4×10?10 m; and wherein, in use, the actuator causes oscillatory motion of one or both end walls in a direction perpendicular to the plane of the end walls; whereby, in use, the axial oscillations of the end walls drive radial oscillations of fluid pressure in the cavity.

Abstract: A miniaturized liquid cooling device (200) includes a heat absorber (20), a heat dissipater (30), a liquid driving device and a plurality of tubes (60) connecting the heat absorber, the heat dissipater and the liquid driving device together to form a loop. The liquid driving device includes a droplet generator (40) and a piezoelectric micro-pump (50). The droplet generator includes a plurality of control electrodes (422) and a reference electrode layer (442) corresponding to the control electrodes. A fluid channel (425) is formed between the control electrodes and the reference electrode layer. The piezoelectric micro-pump includes a piezoelectric block (518) and an oscillating diaphragm (517) capable of co-oscillating with the piezoelectric block for driving the working fluid to unidirectionally flow through a channel (513) defined in the piezoelectric micro-pump.

Abstract: A digital waveform generating circuit having a DC voltage as an input and generating a sinusoidal digital signal, an active filter extracting low-frequency components from the sinusoidal digital signal generated in the digital waveform generating circuit, and a high-voltage control circuit generating a high-voltage drive signal using the sinusoidal digital signal after passing through the active filter are provided. A smooth waveform without steep voltage changes is generated.

Abstract: A diaphragm pump includes: a volume changing member which changes the volume of a fluid chamber; a diaphragm member fixed in a stretched state and arranged separate from the fluid chamber, the diaphragm member having a pair of electrodes and a stretch film formed of dielectric elastomer, and the diaphragm member driving the volume changing member in a forward movement direction; a return bias member which drives the volume changing member in a backward movement direction; and a connection member which connects the diaphragm member and the volume changing member. In a low voltage state, the diaphragm member and the return bias member have driving force with respect to the volume changing member.

Abstract: A compact, high capacity pump for pumping fluid. A first one-way valve is between an inlet port and the pump's fluid chamber. A second one-way valve is between the pump's fluid chamber and an outlet port. A diaphragm separates a piezoelectric stack from the fluid chamber. A power source provides power to the piezoelectric stack causing it to expand and contract. The expansion and contraction of the piezoelectric stack causes fluid to be pumped from the inlet port to the fluid chamber through the first one-way valve and causes fluid to be pumped from the fluid chamber to the outlet port through the second one-way valve. In one preferred embodiment, both one-way valves are disc valves. In another preferred embodiment both one-way valves are MEMS valves.

Abstract: The present invention is a driving circuit applied to a piezoelectric activation element, which comprises: a driving period generation unit and a switch circuit unit.

Abstract: A micropump having a diaphragm portion, a valve portion of an intake-side check valve, and a valve portion of a discharge-side check valve formed in a single elastic-member sheet. A piezoelectric actuator is attached onto a back surface of the diaphragm portion. The elastic-member sheet is sandwiched between a first case member and a second case member, the elastic-member sheet providing sealing between both case members. A vibration chamber is defined between the elastic-member sheet and the first case member, the vibration chamber housing the piezoelectric actuator. A pump chamber is defined between the elastic-member sheet and the second case member.

Abstract: A piezoelectric micropump in which a pump chamber is isolated by a diaphragm. A piezoelectric element is disposed on a back surface of the diaphragm, and the diaphragm is deformed by bending deformation of the piezoelectric element to change the volume of the pump chamber and transport fluid in the pump chamber. A support member for supporting a back surface of the piezoelectric element is provided so that the support member inhibits bending of a peripheral portion of the diaphragm in a reverse direction. The support member thus prevents the piezoelectric element from being floated. Accordingly, the displacement of the piezoelectric element can be reliably transmitted as the change in volume of the pump chamber, thereby enhancing the fluid transportation performance.

Abstract: An electrically-powered fluid sprayer employs a piezoelectric fluid pump that includes an inlet port, an outlet port, a pump chamber, and a piezoelectric element that is deformed and displaced by electrical signals supplied thereto to vary the volume of the pump chamber. Such displacement pumps fluid into the inlet port and into the pump chamber and discharges fluid from the pump chamber out the outlet port. The inlet port is in fluid communication with a fluid reservoir. Spin mechanics may be disposed downstream from the outlet port of the fluid pump and upstream from the discharge nozzle. The piezoelectric fluid sprayer may be extended to include a dual chamber piezoelectric pump that pumps different fluids (e.g., a liquid and air). The output of the dual chamber pump is mixed in a manifold and supplied downstream to the discharge nozzle. Spin mechanics may be employed in the fluid stream upstream from the discharge nozzle after the mixing.

Abstract: A diaphragm air pump includes a diaphragm; and upper and lower housings that interpose the diaphragm such that a variable volume chamber is formed over and under the diaphragm. The diaphragm air pump vibrates the diaphragm to obtain a pump operation, a circular concave portion into which the diaphragm that is circular in plan view is fitted is formed in any one of the upper and lower housings, a ring-shaped groove for housing a seal member is formed in the other, the ring-shaped groove having inner and outer diameters which are set across the circular concave portion, and a ring-shaped elastic seal member which is compressively deformed across the periphery of the diaphragm by the upper and lower housings is housed in the ring-shaped groove.

Abstract: A pump includes a diaphragm vibrated by a piezoelectric element and a case. An inlet orifice and an outlet orifice are disposed on an outer surface of the case. An inlet path connects the inlet orifice to an inlet and an outlet path connects the outlet orifice to an outlet. At least one portion of the inlet orifice and at least one portion of the outlet orifice are positioned higher than the diaphragm in the case, and portions of the inlet path and the outlet path connecting to the inlet orifice and the outlet orifice are positioned higher than the diaphragm.

Abstract: A piezoelectric drive device 2 includes cases 4 and 5 and a drive device body 6. The drive device body 6 includes a displacement expanding plate 10, a biasing unit 15 and piezoelectric elements 17 and 18. The displacement expanding plate includes a body 110 biased to rotate by the biasing unit 15, and a displacement expanding portion 120 expanding a displacement when the piezoelectric elements 17 and 18 are expanded to be displaced relative to the body in a direction perpendicular to an expanding direction of the piezoelectric elements. In a state where no voltage is applied to the piezoelectric element, a first driven object 31 is moved by the body that is biased by the biasing unit. When a voltage is applied to the piezoelectric element 17, a second driven object 32 is moved by the displacement portion 120.

Abstract: Embodiments of the present disclosure may include a piezoelectric pump having: a piezoelectric vibrator whose periphery may be fluid-tightly sealed; and a pump chamber and an air chamber that may be formed on front and rear sides of the piezoelectric vibrator. The piezoelectric vibrator may include: a main shim that may be formed of a conductive thin metal plate; a plurality of piezoelectric element layers that may be formed on the main shim; and an intermediate shim that may be formed between the plurality of piezoelectric element layers and may be made of an elastic metal material having mechanical recovery. The piezoelectric vibrator may be vibrated to perform a pumping operation.

Abstract: Embodiments of the present disclosure may include a piezoelectric pump having: a piezoelectric vibrator including a main shim that may be formed of a conductive thin metal plate and a piezoelectric element layer that may be formed on the main shim; and a pair of ring-shaped support members that may support front and rear sides of a circumferential portion of the piezoelectric vibrator such that a pump chamber and an air chamber formed on the front and rear sides of the piezoelectric vibrator may be fluid-tightly sealed. The ring-shaped support members may support both sides of a circumferential portion of the piezoelectric element layer of the piezoelectric vibrator, and the piezoelectric vibrator may be vibrated to perform a pumping operation.

Abstract: A piezoelectric pump includes a piezoelectric vibrator whose periphery is fluid-tightly sealed, and a pump chamber and an air chamber that are formed on front and rear sides of the piezoelectric vibrator. The piezoelectric pump vibrates the piezoelectric vibrator to perform a pumping operation. The piezoelectric vibrator includes: a shim that is formed of a conductive thin metal plate and has one surface abutting on the pump chamber; and a laminate of a plurality of piezoelectric element layers that is formed on the other surface of the shim so as to face the air chamber or the pumping chamber. The plurality of piezoelectric element layers are polarized and connected to wiring lines such that the amplitude of the vibration of the piezoelectric vibrator is larger than that of a piezoelectric vibrator including a single-layer piezoelectric element.

Abstract: The present invention relates to a pump unit or the like which feeds particles in a liquid with particles dispersed therein to a predetermined area. An object of the present invention is to obtain a sufficient solution feeding resolution while inhibiting mixture of bubbles. The pump unit includes a moving mechanism 13 that moves a pump 12 and a reservoir 11 relative to each other to vary the positional relationship between a tip 1221 of the pump 12 and an edge 112 of the opening 111 between a separating relationship in which the tip 1221 is separated upward from the edge 112 of the opening 111 in a liquid reserved in the reservoir 11 and a pressing relationship in which the tip 1221 is pressed against the edge 112. In the separating positional relationship, the pump 12 performs a sucking operation to take particles C into its interior. In the pressing relationship, the pump 12 performs an ejecting operation to deliver the particles C.

Abstract: Devices employing electroactive polymer actuators are disclosed. The devices include pumps, valves, cameras (where electroactive polymer actuators control either one or both of zoom and focus), vibrators (for inclusion in cell phones, game console controls, etc.) and audio speakers. These devices advantageously incorporate the actuator configurations described. The devices generally incorporate a diaphragm-type actuation having a central section of material that is less flexible than adjacent material.

Abstract: A piezoelectric pump includes a casing formed of a plurality of metallic members welded and thus joined together, a piezoelectric element dividing an internal space of the casing into a working space and a back pressure space, and internal components formed of resin, and provided between the casing and the piezoelectric element and holding the piezoelectric element. The internal components are formed of workable and moldable resin. The internal component defines a perimeter of the working space and the internal component defines a perimeter of the back pressure space. The internal components are arranged opposite each other to form a recess therebetween to receive and thus hold the piezoelectric element therein.

Abstract: A microvalve sensor for sensing fluid flow therethrough and generating an electrical signal indicative thereof comprises: a housing connectable inline with a fluid passageway; a microvalve disposed in the housing to permit fluid to flow unidirectionally through the housing, the microvalve including: a substrate; an insulating layer disposed over the substrate, the substrate and insulating layer including an orifice to accommodate fluid flow through the housing; and a diaphragm element disposed over the insulating layer, the diaphragm element including: a solid center portion having an area sufficient to cover the orifice, and an outer portion surrounding the center portion having a plurality of apertures for passing fluid from the orifice through the housing, the outer portion being affixed to the insulating layer around a periphery thereof, the diaphragm element and substrate forming opposite plates of a capacitor having a capacitance which changes with fluid flow through the housing; and a circuit coupled a

Abstract: There is provided a piezoelectric pump including a piezoelectric vibrator formed by stacking a piezoelectric body on at least one of the front and rear surfaces of a shim made of a conductive metal thin plate, and a housing that makes the peripheral edge of the piezoelectric vibrator liquid-tight to form a pump chamber. An alternating current is applied to between the shim of the piezoelectric vibrator, and the piezoelectric body to vibrate the piezoelectric vibrator, thereby generating a pumping action. A cylindrical bent part is formed at a peripheral edge of the shim of the piezoelectric vibrator, and a liquid-tight seal member is interposed between the cylindrical bent part and the housing. As a result, the piezoelectric pump with a highly-reliable fluid-tight structure around the piezoelectric vibrator is obtained.

Abstract: A piezoelectric drive device 2 includes cases 4 and 5 and a drive device body 6. The drive device body 6 includes a displacement expanding plate 10, a biasing unit 15 and piezoelectric elements 17 and 18. The displacement expanding plate includes a body 110 biased to rotate by the biasing unit 15, and a displacement expanding portion 120 expanding a displacement when the piezoelectric elements 17 and 18 are expanded to be displaced relative to the body in a direction perpendicular to an expanding direction of the piezoelectric elements. In a state where no voltage is applied to the piezoelectric element, a first driven object 31 is moved by the body that is biased by the biasing unit. When a voltage is applied to the piezoelectric element 17, a second driven object 32 is moved by the displacement portion 120.

Abstract: A pump comprises a diaphragm assembly which includes a first diaphragm (22) having a first diaphragm edge (28) and a second diaphragm (24) having a second diaphragm edge (30). The first diaphragm edge (28) and the second diaphragm edge (30) are bonded together so that a bellows chamber (26) is formed between the first diaphragm (22) and the second diaphragm (24). At least one and possibly both of the first diaphragm (22) and the second diaphragm (24) is a piezoelectric diaphragm which displaces in accordance with application of an electrical signal. A driver applies the electrical signal to whichever of the first diaphragm (22) and the second diaphragm (24) is the piezoelectric diaphragm. The first diaphragm and the second diaphragm bow outwardly together and shrink in diameter during a suction stroke but flatten out and increase in diameter during a pump stroke.

Abstract: An electronic apparatus includes a housing having a heat generating component, a heat radiating portion which radiates heat generated by the heat generating component, a pump unit having an impeller and a heat receiving portion thermally connected to the heat generating component, wherein the pump unit supplies liquid to the heat radiating portion by rotating the impeller, and a circulation path which circulates the liquid between the heat receiving portion and the heat radiating portion and transfers the heat generated by the heat generating component to the heat radiating portion through the liquid. The pump unit is arranged such that the center of the impeller is deviated from the center of the heat generating component.

Abstract: The fluid-flow device (100) of the invention comprises a stack (30) covered by a closure wafer (20), said stack (30) comprising a support wafer (36), a layer of insulating material (34), and a silicon layer (32). The closure wafer (20) and/or said silicon layer (32) are machined so as to define a cavity (38) between said closure wafer (20) and said silicon layer (32), said support wafer (36) has at least one duct (102) passing right through it, said layer of insulating material (34) presenting at least one zone (35) that is entirely free of material placed at least in line with said duct (102) so as to co-operate with said cavity (38) to define a moving member (40) in said silicon layer (32), the moving member being suitable under the pressure of liquid in said cavity (38) for reversibly moving towards said support wafer (36) until contact is made between said moving member (40) and said support wafer (36).

Abstract: A display device for a portable instrument includes at least a first transparent or semi-transparent plate arranged on a bottom element. Several closed cavities are formed at least in part in the first plate in the field of view of the device to display information. Each cavity is connected by a respective channel through the bottom element to a tank of coloured fluid via feed means for filling or emptying each closed cavity of coloured fluid for displaying information. The feed means include at least one micropump connected by an inlet pipe to the coloured fluid tank, and microvalves connected to the micropump by a common outlet pipe. Each cavity is directly connected via its respective channel to a corresponding microvalve. The micropump and the microvalves are controlled by electric signals from control means, which can be clocked by a time base in order to control display of time information.

Abstract: A micropump check valve device which can be designed thin with good assemblability and applied with urging force. The micropump check valve device includes an upstream side member having a small-bore hole for passing therethrough a fluid, a downstream side member having a large-bore hole for passing therethrough the fluid, and a valve member having a valve mechanism sandwiched between the upstream side member and the downstream side member. The valve mechanism includes a passing hole formed in correspondence to a position and a size of the large-bore hole in the downstream side member, a contacting part formed inside the passing hole in correspondence to the position and size of the small-bore hole in the upstream side member thereby to close the small-bore hole, and supporting parts formed to bridge across the passing hole to support the contacting part. The valve member has a greater linear expansion coefficient than the upstream side and downstream side members.

Abstract: A drive circuit (18) produces a drive signal having a waveform of a predetermined waveform shape for a device (10) having a piezoelectric actuator (14). The drive circuit (14) includes a memory (140) which stores waveform shape data which is utilized by the drive circuit in producing the drive signal. The drive circuit utilizes the waveform shape data so that, for each of plural points comprising a period of the waveform, the drive signal has an appropriate amplitude for the predetermined waveform shape. The waveform shape data has preferably been prepared to optimize one or more operational parameter(s) of the device. Preferably the waveform shape data has been prepared by solving a waveform equation, the waveform equation having coefficients determined to optimize at least one operational parameter of the device.

Abstract: A drive circuit (18) produces a drive signal for a pump (10) having a piezoelectric actuator (14), with the piezoelectric actuator (14) forming a part of the drive circuit (18) and serving to shape a waveform of the drive signal. The drive circuit (18) comprises a pulse generator (100) which generates pulses; a converter circuit (102) which receives the pulses and produces charge packets at a rate which equals a desired drive frequency; and, the piezoelectric actuator (14). The piezoelectric actuator (14) receives the charge packets and, by its capacitive nature, integrates the charge packets to shape the waveform of the drive signal. Preferably, the piezoelectric actuator (14) integrates the charge packets to yield a drive field that approximates a sine wave. In one non-limiting example embodiment, the pulse generator (100) comprises a microcontroller-based pulsed width modulator (PWM) circuit (116) and the converter circuit (102) comprises a flyback circuit.

Abstract: A micro-pump having a first layer, a second layer and an intermediate flexible layer is disclosed. The first layer and second layer may be of moldable plastics. The intermediate layer may be a substantially flat PDMS membrane layer having an inlet hole and an outlet hole. The first layer and the second layer are disposed on either side of the intermediate layer to define a pumping chamber that encloses an actuatable portion of the intermediate layer and valve seats that abut the inlet hole and the outlet hole of the intermediate layer. The actuatable portion is moveable to increase and reduce the volume of the pumping chamber to allow pressure to lift the respective intermediate layer portions surrounding the inlet hole and the outlet hole to thereby draw fluid and expel fluid from the pumping chamber respectively.

Abstract: This invention provides a fluid pump using perforate elements and closure elements which are alternately displace and relates particularly but not exclusively to miniature fluid pumps and pumps suitable for delivery of liquid pharmaceutical formulations. In the art of miniature liquid pumps are known pumps based on peristaltic and “pump chamber” principles. (Peristaltic pumps may be used to pump fluids in general, that is, liquids or gases). Both types of pump are used in ambulatory pump products for delivery of liquid medicaments, for which application miniaturization and low weight are important attributes.

Abstract: A measuring device for measuring in an ear canal includes a probe for insertion into an ear canal having an opening for letting air in to and out of the ear canal, and a pump for providing a pressure above a surrounding atmospheric pressure or below the surrounding atmospheric pressure, the pump including a housing with openings for inlet and/or outlet, where within the housing a piston element having piezo electric properties is disposed, one opening in the pump being operatively connected to the opening in the probe.

Abstract: The present invention relates to a process for production of chlorine dioxide by reacting in a reaction vessel an alkali metal chlorate, sulfuric acid and a reducing agent, preferably methanol, in proportions to generate chlorine dioxide in a reaction medium maintained at a temperature from about 50.degree. C. to about 100.degree. C. and an acidity within the interval from 4.8 to 11 N and subjected to a subatmospheric pressure sufficient to effect evaporation of water. A mixture of chlorine dioxide and water vapour is withdrawn from an evaporation region in the reaction vessel and alkali metal sulfate is precipitated in a crystallization region in the reaction vessel. The alkali metal sulfate, which is an alkali metal sesquisulfate, from the crystallization region is heated to the formation of gaseous sulfur trioxide and a neutral alkali metal sulfate. The gaseous sulfur trioxide is absorbed in water to the formation of sulfuric acid.