US20050019180A1 - Pump - Google Patents

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Publication number
US20050019180A1
US20050019180A1 US10/866,119 US86611904A US2005019180A1 US 20050019180 A1 US20050019180 A1 US 20050019180A1 US 86611904 A US86611904 A US 86611904A US 2005019180 A1 US2005019180 A1 US 2005019180A1
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United States
Prior art keywords
pump chamber
pump
chamber
passage
working fluid
Prior art date
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Abandoned
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US10/866,119
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English (en)
Inventor
Takeshi Seto
Kunihiko Takagi
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Seiko Epson Corp
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Seiko Epson Corp
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Assigned to SEIKO EPSON CORPORATION reassignment SEIKO EPSON CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SETO, TAKESHI, TAKAGI, KUNIHIKO
Publication of US20050019180A1 publication Critical patent/US20050019180A1/en
Abandoned legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B23/00—Pumping installations or systems
    • F04B23/04—Combinations of two or more pumps
    • F04B23/06—Combinations of two or more pumps the pumps being all of reciprocating positive-displacement type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B43/00—Machines, pumps, or pumping installations having flexible working members
    • F04B43/02—Machines, pumps, or pumping installations having flexible working members having plate-like flexible members, e.g. diaphragms
    • F04B43/04—Pumps having electric drive
    • F04B43/043—Micropumps
    • F04B43/046—Micropumps with piezoelectric drive

Definitions

  • the present invention relates to a pump to move a working fluid by varying a volume of a pump chamber by a piston or a movable wall, such as a diaphragm, and specifically to a small high-power pump.
  • a related art volume pump including a diaphragm to be driven with a piezoelectric element, such as a PZT, a pump chamber whose volume can be varied by the diaphragm, a hole to allow a fluid to flow into the pump chamber, and a hole to allow the fluid to flow out of the pump chamber, check valves being provided in the respective holes (see, for example, Japanese Unexamined Patent Application Publication No. 61-171891.
  • the present invention provides a pump capable of discharging gas bubbles and thus maintaining a discharging ability, even when the gas bubbles stay inside a pump chamber.
  • a pump includes a pump chamber whose volume can be varied by driving a piston or a movable wall, an inlet passage to allow a working fluid to flow into the pump chamber, an outlet passage to allow the working fluid to flow out of the pump chamber, and a fluid resistance element to open and close at least the inlet passage.
  • a resultant inertance value of the inlet passage is set to be smaller than a resultant inertance value of the outlet passage.
  • a bubble discharging device to discharge gas bubbles remaining in the pump chamber is further provided.
  • a diaphragm which is driven with an actuator, such as a piezoelectric element, may be used as the movable wall.
  • a check valve may be used as the fluid resistance element.
  • a secondary pump chamber a pressurizing mechanism, a heating section, etc., which is used to apply a pressure to the pump chamber, may be used.
  • the pump since the pump includes the bubble discharging device, the pump can be started even when gas bubbles stay in the pump chamber. Specifically, even when the working fluid is not filled in the pump chamber. Further, when the gas bubbles stay in the pump chamber, although it is considered that the pressure in the pump chamber is not sufficiently raised, the staying gas bubbles can be discharged in driving the pump, due to the aforementioned bubble discharging device. So it is possible to maintain performance of the pump, specifically, the discharge amount of the working fluid.
  • the pump chamber may include a primary pump chamber which communicates with the outlet passage and whose volume can be varied by driving a piston or a movable wall, and a secondary pump chamber which communicates with the inlet passage and functions as the bubble discharging device and whose volume can be varied by driving a movable wall.
  • the secondary pump chamber as the bubble discharging device since the secondary pump chamber as the bubble discharging device is provided at the inlet passage side, the working fluid of the inlet passage can be transferred to the primary pump chamber by driving the secondary pump chamber.
  • the pressure in the primary pump chamber can be raised, so that it is possible to discharge the gas bubbles in the primary pump chamber.
  • the pump having the above construction may include a primary pump chamber inlet passage to allow the working fluid to flow into the primary pump chamber; a primary pump chamber outlet passage to allow the working fluid to flow out of the primary pump chamber; a secondary pump chamber inlet passage to allow the working fluid to flow into the secondary pump chamber; and a secondary pump chamber outlet passage to allow the working fluid to flow out of the secondary pump chamber, and the primary pump chamber inlet passage be the secondary pump chamber outlet passage.
  • the primary pump chamber inlet passage is also used as the secondary pump chamber outlet passage, the flow passage of the working fluid is shortened.
  • the size of the pump can be decreased, so that it is possible to reduce the fluid resistance of the flow passage.
  • the pump according to an aspect of the present invention may include a fluid resistance element to open and close the primary pump chamber inlet passage; a fluid resistance element to open and close the secondary pump chamber inlet passage; and a fluid resistance element to open and close the secondary pump chamber outlet passage, and the fluid resistance element to open and close the primary pump chamber inlet passage may be the fluid resistance element to open and close the secondary pump chamber outlet passage.
  • a check valve as the fluid resistance element of the secondary pump chamber inlet passage
  • the working fluid of which the pressure has been raised in the secondary pump chamber
  • a check valve as the fluid resistance element of the primary pump chamber inlet passage
  • the fluid resistance element to open and close the primary pump chamber inlet passage is the fluid resistance element to open and close the secondary pump chamber outlet passage
  • two check valves, as the fluid resistance elements are enough for two pump chambers. So it is possible to simplify the structure of the pump, to reduce the number of components, and thus to accomplish low cost. Furthermore, it is also possible to reduce the fluid resistance.
  • the movable wall provided in the secondary pump chamber may be a diaphragm in which a piezoelectric element is attached to at least one surface thereof, and the secondary pump chamber and the diaphragm constitute a unimorph pump or a bimorph pump.
  • the secondary pump chamber can be constructed using a piezoelectric element attached to the diaphragm used in related art pulsation reducing device for a flow passage. Further, since the unimorph pump and the bimorph pump have a large amount of displacement of the diaphragm even under a low pressure, they can combine the functions of the secondary pump chamber as a pulsation absorbing device and the aforementioned bubble discharging device.
  • the pump having the above construction may include a driving switch control unit for switching the driving between the secondary pump chamber and the primary pump chamber.
  • the driving switch control unit for example, when the driving of the pump is started, the inner gas bubbles can be discharged by first driving the secondary pump chamber and then driving the primary pump chamber. Then the primary pump chamber is continuously driven or the primary pump chamber and the secondary pump chamber can be alternately driven, so that it is possible to obtain a stable discharge amount of working fluid during the driving of the pump.
  • a driving electrode and a detecting electrode may be formed in the piezoelectric element.
  • the state of the secondary pump chamber can be detected. Specifically, variation in the inside pressure of the secondary pump chamber can be detected as displacements of the piezoelectric element. It is thus possible to control the primary pump chamber and the secondary pump chamber correspondingly to the variation in pressure by using the above-mentioned driving switch control unit.
  • the pump according to an aspect of the present invention may include a pressure detecting section to detect an inside pressure of the primary pump chamber.
  • the state inside the primary pump chamber can be detected. So it is possible to efficiently drive the pump correspondingly to the state inside the primary pump chamber.
  • the above-mentioned pump according to an aspect of the present invention may include a pressurizing mechanism serving as the bubble discharging device to raise and maintain the pressure of the working fluid existing in the pump chamber.
  • the pressure of the working fluid in the pump chamber can be raised and maintained by the pressurizing mechanism.
  • the volume of the gas bubbles is decreased, it is possible to discharge the gas bubbles in the pump chamber by compressing the volume of the pump chamber through driving the piston or the movable wall, such as a diaphragm.
  • the pressurizing mechanism may include a variable-volume chamber and a flow passage to allow the variable-volume chamber and the outlet passage to communicate with each other.
  • the pressurizing mechanism can simply generate a high pressure in the pump chamber communicating with the outlet passage.
  • variable-volume chamber may be formed of an elastic member.
  • variable-volume chamber out of the elastic member, the pressure can be smoothly raised due to the introduction of the working fluid into the variable-volume chamber. Damages on the components constituting the pump due to the pressure can be reduced or prevented. Further, the variable-volume chamber also functions to reduce the pressure pulsation in the outlet passage. As a result, it is possible to reduce or prevent the variation in pump ability from occurring due to influence of an external pipe to be connected to the outlet passage.
  • the pressurizing mechanism may include a volume varying mechanism to apply a pressure to vary the volume of the variable-volume chamber.
  • an actuator may be employed as the volume varying mechanism.
  • volume varying mechanism to vary the volume of the variable-volume chamber since the volume varying mechanism to vary the volume of the variable-volume chamber is provided, it is possible to control the volume of the variable-volume chamber correspondingly to the state of the pump chamber.
  • the pressurizing mechanism may include a passage switching section to switch between a first mode where the working fluid flowing out of the pump chamber is introduced into the variable-volume chamber and a second mode where the working fluid flowing out of the pump chamber is isolated from the variable-volume chamber.
  • the pump having the above construction may include a pressure detecting section to detect an inside pressure of the variable-volume chamber.
  • the pressure detecting device may be provided in the pump chamber.
  • the inside pressure of the variable-volume chamber which is pressurized by the pressurizing mechanism, may range from about one atmosphere to about five atmospheres in a gauge pressure.
  • the pressurizing mechanism may include a variable-volume chamber, a flow passage communicating with the outlet passage, and an opening and closing member to open and close the flow passage.
  • the pressurizing mechanism may be detachable from the outlet passage.
  • the variable-volume chamber and the outlet passage may be allowed to communicate with each other by fitting the pressurizing mechanism into the outlet passage.
  • the pump according to an aspect of the present invention may include a heating section serving as the bubble discharging device provided in the pump chamber.
  • the gas bubbles are moved from the stagnation points in the pump chamber by heating the staying gas bubbles with the heating section provided in the pump chamber and thus increasing the volume of the staying gas bubbles, so that it is possible to easily discharge the gas bubbles.
  • the heating section may be received inside the wall of the pump chamber, or be arranged in a comer portion of the pump chamber.
  • the gas bubbles tend to stay at the comer portions of the pump chamber or at the protruded wall portions of the pump chamber. Accordingly, by receiving the heating section inside the wall of the pump chamber without generating any protruded portion, or by arranging the heating section at least at the comer portion of the pump chamber, it is possible to make the gas bubbles not stay or to discharge the staying gas bubbles from the corner portions of the pump chamber where the gas bubbles tend to stay.
  • a plurality of the heating sections may be provided.
  • the above-mentioned pump may include a pressure detecting section for detecting an inner pressure of the pump chamber.
  • a heating signal may be input to the heating section.
  • a pulse-shaped heating signal may be input to the heating section.
  • the piston or the movable wall may be driven in synchronism with the heating signal.
  • the aforementioned pump allows the heating section to heat the working fluid in a pulse shape and allows the diaphragm to operate in synchronism with the pulse, it is possible to reduce the amount of energy consumed in the heating section, and to effectively discharge the gas bubbles staying in the pump chamber.
  • the heating section may heat the working fluid to change the phase of the working fluid in contact with the heating section.
  • FIG. 1 is a vertical cross-sectional schematic illustrating a pump according to a first exemplary embodiment of the present invention
  • FIG. 2 is a graph illustrating inner states of the pump according to the first exemplary embodiment of the present invention
  • FIG. 3 is a schematic illustrating a driving circuit of the pump according to the first exemplary embodiment of the present invention
  • FIG. 4 is a schematic illustrating a diaphragm for a secondary pump chamber of a pump according to a second exemplary embodiment of the present invention
  • FIG. 5 is a vertical cross-sectional schematic illustrating a part of a pump according to a third exemplary embodiment of the present invention.
  • FIG. 6 is a schematic illustrating a driving circuit of the pump according to the third exemplary embodiment of the present invention.
  • FIG. 7 is a vertical cross-sectional schematic illustrating a pump according to a fourth exemplary embodiment of the present invention.
  • FIG. 8 is a schematic illustrating a driving circuit of the pump according to the fourth exemplary embodiment of the present invention.
  • FIG. 9 is a vertical cross-sectional schematic illustrating a pump according to a fifth exemplary embodiment of the present invention.
  • FIG. 10 is a vertical cross-sectional schematic illustrating a pressurizing mechanism according to a sixth exemplary embodiment of the present invention.
  • FIG. 11 is a vertical cross-sectional schematic illustrating a part of a pump according to the sixth exemplary embodiment of the present invention.
  • FIG. 12 is a vertical cross-sectional schematic illustrating a part of a pump according to a seventh exemplary embodiment of the present invention.
  • FIG. 13 is a schematic illustrating a heater according to the seventh exemplary embodiment of the present invention.
  • FIG. 14 is a schematic illustrating a modified example of the heater according to the seventh exemplary embodiment of the present invention.
  • FIG. 15 is a schematic illustrating a driving circuit of the pump of the seventh exemplary embodiment of the present invention.
  • FIG. 16 is a schematic illustrating another modified example of the heater according to the seventh exemplary embodiment of the present invention.
  • FIG. 17 is a vertical cross-sectional schematic illustrating a pump according to another exemplary embodiment of the present invention.
  • FIGS. 1 to 17 The exemplary embodiments of the present invention are shown in FIGS. 1 to 17 .
  • FIGS. 1 to 3 show a pump 10 according to a first exemplary embodiment.
  • FIG. 1 is a vertical cross-sectional schematic illustrating a structure of the pump 10 according to the first exemplary embodiment of the present invention.
  • the pump 10 includes a cup-shaped case 50 to which a laminated piezoelectric element 70 is fixed, an inflow passage 21 to introduce a working fluid, an outflow passage 28 to discharge the working fluid, and a pump case 20 having a secondary pump chamber 24 and a primary pump chamber 27 .
  • One end of the laminated piezoelectric element 70 is fixed to an inside bottom portion of the case 50 through a fixing device, such as adhesive.
  • a primary pump chamber diaphragm 60 is closely fixed to both of a top surface of an edge portion of the case 50 and a top surface of the other end of the laminated piezoelectric element 70 .
  • the pump case 20 is fixed to the circumferential edge portion of the top surface of the primary pump chamber diaphragm 60 such that the airtightness of the fixed portions is maintained.
  • the primary pump chamber 27 is formed in a space between the primary pump chamber diaphragm 60 and a concave portion formed in a lower portion of the pump case 20 .
  • a concave portion is provided in an upper portion of the pump case 20 .
  • the secondary pump chamber diaphragm 45 is airtightly fixed to a top surface of an edge portion of the concave portion, thereby forming the secondary pump chamber 24 .
  • the secondary pump chamber diaphragm 45 is formed out of a plate member thinner than the primary pump chamber diaphragm 60 , and is deformable with the inside pressure of the secondary pump chamber 24 .
  • a plate-shaped piezoelectric element 71 is fixed to a top surface of the secondary pump chamber diaphragm 45 .
  • the secondary pump chamber diaphragm 45 and the plate-shaped piezoelectric element 71 form a unimorph actuator.
  • the plate-shaped piezoelectric element 71 may be attached to both surfaces of the secondary pump chamber diaphragm 45 to form a bimorph actuator. In this case, the close attachment of the plate-shaped piezoelectric element 71 in contact with the working fluid should be noted, while an actuator having a larger displacement can be formed.
  • the inflow passage 21 is formed in an inlet connection tube 30 protruded from the pump case 20 , and communicates with the secondary pump chamber 24 through an inlet valve hole 22 for the secondary pump chamber and an inlet valve fitting hole 23 for the secondary pump chamber.
  • An inlet check valve 41 for the secondary pump chamber as a fluid resistance element to open and close the inlet valve hole 22 for the secondary pump chamber is fixed to the edge of the inlet valve fitting hole 23 for the secondary pump chamber.
  • An inlet valve hole 25 for the primary pump chamber and an inlet valve fitting hole 26 for the primary pump chamber are provided between the secondary pump chamber 24 and the primary pump chamber 27 .
  • An inlet check valve 42 for the primary pump chamber as a fluid resistance element, including an opening and closing member which can open and close the inlet valve hole 25 for the primary pump chamber, is fixed to the edge of the inlet valve fitting hole 26 for the primary pump chamber.
  • the primary pump chamber 27 communicates with the outflow passage 28 .
  • the outflow passage 28 has a narrow tube portion connected to the primary pump chamber 27 and a wide tube portion of which a sectional area is enlarged from an intermediate portion of the narrow tube portion, which are formed continuously.
  • An outer circumferential portion of the outlet passage constitutes the outlet connection tube 31 .
  • tubes made of silicon rubber having elasticity are connected to the inlet connection tube 30 and the outlet connection tube 31 .
  • an inertance value L of a flow passage is defined.
  • a sectional area of the flow passage is S
  • a length of the flow passage is r
  • a density of the working fluid is ⁇
  • a pressure difference of the flow passage is ⁇ P
  • a flow volume of the working fluid flowing in the flow passage is Q.
  • the inertance value L indicates a degree of influence of a unit pressure on a variation of flow volume per unit time, where the variation of flow volume per unit time becomes smaller with increase of the inertance value L and the variation of flow volume per unit time becomes larger with decrease of the inertance value L.
  • the resultant inertance value, about a parallel connection of a plurality of flow passages or a serial connection of a plurality of flow passages having different shapes may be calculated by composing inertance values of the respective flow passages similarly to the parallel connection or the serial connection of inductances in electric circuits. For example, when two flow passages having inertance values of L 1 and L 2 , respectively, are connected in series, the resultant inertance value is given as L 1 +L 2 .
  • the inlet passage described hereinafter refers to a flow passage extending from the inside of the primary pump chamber 27 to an inlet end surface of the inlet valve hole 25 for the primary pump chamber.
  • the inlet passage refers to a flow passage extending from the inside of the primary pump chamber 27 to a connection portion of the pulsation absorbing device.
  • the secondary pump chamber diaphragm 45 has a high rigidity and thus a small pulsation absorbing effect, it is necessary to calculate the resultant inertance value of the primary pump chamber inlet passage up to the position of the pulsation absorbing device, such as a tube at the upstream of the secondary pump chamber 24 .
  • the outlet passage refers to a flow passage extending up to an outlet end surface of the outflow passage 28 , because the tube serving as the pulsation absorbing device is connected to the outlet connection tube 31 .
  • the inertance value of an opening and closing member of the check valve is defined.
  • the inertance value of the opening and closing member indicates a degree of influence of a unit pressure on the variation of flow volume per unit time, similarly to the inertance value of the flow passage, where the variation of flow volume per unit time becomes smaller with increase of the inertance value and the variation of flow volume per unit time becomes larger with decrease of the inertance value.
  • FIG. 1 will be also referred to.
  • FIG. 2 is a graph illustrating as waveforms relations of a driving voltage (V) of the laminated piezoelectric element 70 and a pressure (MPa) of the primary pump chamber 27 expressed in an absolute pressure with respect to a time (ms), when the primary pump chamber 27 and the secondary pump chamber 24 are filled with the working fluid which is a liquid (water) in the pump 10 according to the first exemplary embodiment of the present invention.
  • V driving voltage
  • MPa pressure
  • the pressure starts its increase due to the compression of the primary pump chamber 27 after passing through a trough of the driving voltage.
  • the inside pressure of the primary pump chamber 27 is rapidly decreased after passing through a point of the driving voltage having an largest upward slope, and is dropped substantially down to an absolute pressure of 0 .
  • the inside pressure of the primary pump chamber 27 is largely increased due to the large inertance of the outflow passage (outlet passage) 28 .
  • the working fluid in the small tube portion is accelerated.
  • the kinetic energy generating an inertia effect is accumulated.
  • the inlet check valve 42 for the primary pump chamber is opened due to the pressure difference, so that the working fluid flows in the primary pump chamber 27 from the secondary pump chamber 24 .
  • the sum of the resultant inertance value of the inlet passage of the primary pump chamber 27 and the inertance value of the inlet check valve 42 for the primary pump chamber serving as the opening and closing member is smaller enough than the inertance value of the outlet passage described above, the efficient inflow of the working fluid is caused.
  • the pump 10 since the discharge and suction are continued for a long time, it is possible to allow a large flow volume to flow. Since the inside of the pump chamber has a very high pressure, it is possible to cope with a high load pressure.
  • the secondary pump chamber diaphragm 45 absorbs the pulsation through deformation by the inside pressure of the secondary pump chamber 24 .
  • the inflow of the working fluid from the inflow passage 21 having a large inertance value to the secondary pump chamber 24 is a static flow having a small pulsation, and the inlet check valve 41 for the secondary pump chamber is continuously opened.
  • the secondary pump chamber diaphragm 45 has an effect of suppressing the pulsation of the inflow passage 21 while keeping the inertance value of the inlet passage of the primary pump chamber 27 small through its deformation.
  • a problem such as generation of fluid resistance or fatigue failure does not occur.
  • FIG. 3 is a schematic of a driving circuit system according to the first exemplary embodiment of the present invention.
  • a priming action is an action that in a case where gas bubbles stay in the pump, a liquid is filled using another pump when the primary pump chamber 27 , not having an ability of voluntarily absorbing the liquid, is started.
  • FIG. 3 is a schematic of a driving circuit system according to the first exemplary embodiment of the present invention.
  • a priming action is an action that in a case where gas bubbles stay in the pump, a liquid is filled using another pump when the primary pump chamber 27 , not having an ability of voluntarily absorbing the liquid, is started.
  • the driving circuit system of the pump 10 includes the laminated piezoelectric element 70 to drive the primary pump chamber diaphragm 60 , the plate-shaped piezoelectric element 71 to drive the secondary pump chamber diaphragm 45 , a switching circuit 85 serving as a driving switch control unit to switch the driving between the laminated piezoelectric element 70 and the plate-shaped piezoelectric element 71 , and a pump driving control circuit 80 to control the driving of the pump 10 .
  • a driving voltage generated by the pump driving control circuit 80 is applied to the plate-shaped piezoelectric element 71 attached to the secondary pump chamber diaphragm 45 by he switching circuit 85 at an initial stage of the pump operation.
  • the driving voltage has, for example, a sine waveform. Since the secondary pump chamber 45 is formed out of a thin plate member and constitutes a unimorph actuator having a large amount of displacement, the second pump chamber 24 causes large variation in volume with the driving voltage.
  • the inlet check valve 41 for the secondary pump chamber is arranged at the inlet side of the secondary pump chamber 24 , and the inlet check valve 42 for the primary pump chamber is arranged at the outlet side thereof.
  • the inlet check valve 42 for the primary pump chamber functions as the outlet check valve of the secondary pump chamber 24 .
  • the secondary pump chamber 24 since the secondary pump chamber 24 includes the check valves at both of the inlet and outlet and thus has a large amount of variation in volume, the secondary pump chamber functions as a pump capable of transferring both gas and liquid. Since the secondary pump chamber 24 and the primary pump chamber 27 discharge the gas and thus are filled with the liquid which is the working fluid, the pump can operate through variation in volume of the primary pump chamber 27 .
  • the switching circuit 85 is switched to apply the driving voltage to the laminated piezoelectric element 70 after sufficient time passes through a timer (not shown), thereby automatically enabling high-power operation.
  • the primary pump chamber 27 it is possible to detect the operating condition of the secondary pump chamber diaphragm 45 by detecting a terminal voltage of the plate-shaped piezoelectric element 71 .
  • the amount of operation of the secondary pump chamber diaphragm 45 is decreased.
  • the priming action is executed by performing the aforementioned driving control.
  • the secondary pump chamber 24 since the secondary pump chamber 24 includes the check valves 41 , 42 at both of the inlet and outlet and thus has a large amount of variation in volume, the secondary pump chamber functions as a pump capable of transferring both of the gas and the liquid. Since the secondary pump chamber 24 and the primary pump chamber 27 discharge the gas and thus are filled with the liquid which is the working fluid, the pump can operate through variation in volume of the primary pump chamber 27 .
  • the switching circuit 85 is switched to apply the driving voltage to the laminated piezoelectric element 70 of the primary pump chamber 27 after sufficient time passes through the timer, thereby automatically enabling the high-power operation.
  • the secondary pump chamber diaphragm 45 it is possible to detect the operating condition of the secondary pump chamber diaphragm 45 by detecting the terminal voltage of the plate-shaped piezoelectric element 71 . In a case where gas bubbles in the working fluid stay in the primary pump chamber 27 to deteriorate the pump ability, the amount of operation of the secondary pump chamber diaphragm 45 is decreased. At that time, by allowing the secondary pump chamber diaphragm 45 to operate by he plate-shaped piezoelectric element 71 , thus discharging the gas bubbles, and then switching the driving voltage such that the primary pump chamber diaphragm 60 is driven by the laminated piezoelectric element 70 , the pump ability can be recovered.
  • the primary pump chamber inlet passage is the secondary pump chamber outlet passage and the fluid resistance element (the check valve 42 ) to open and close the primary pump chamber inlet passage is the fluid resistance element to open and close the secondary pump chamber outlet passage, the flow passage of the working fluid is shortened, so that it is possible to reduce the fluid resistance of the flow passage. As a result, it is possible to simplify the structure of the pump 10 and to reduce the number of components, thereby realizing low cost.
  • the pump according to the second exemplary embodiment has a basic structure similar to the aforementioned first exemplary embodiment, but is different from the first exemplary embodiment in that a part of a driving electrode 52 attached to the plate-shaped piezoelectric element 71 of the secondary pump chamber 24 is separated and forms a detecting electrode 53 .
  • FIG. 4 is a schematic of the pump according to the second exemplary embodiment as seen from the secondary pump chamber diaphragm side.
  • a part of the electrode 52 formed on the plate-shaped piezoelectric element 71 attached to the top surface of the secondary pump chamber diaphragm 45 is separated to form the detecting electrode 53 .
  • the detecting electrode 53 is isolated, it is possible to detect movement of the secondary pump chamber diaphragm 45 even during the priming action (when the driving voltage is applied to the plate-shaped piezoelectric element 71 ).
  • the detecting electrode 53 since the detecting electrode 53 is isolated, it is possible to detect the movement of the secondary pump chamber diaphragm 45 during the priming action, and to accurately detect the timing when the priming action is completed, so that it is possible to switch the driving voltage toward the laminated piezoelectric element 70 of the primary pump chamber diaphragm 60 for a short time.
  • the pump according to the third exemplary embodiment has a basic structure similar to the aforementioned first exemplary embodiment, but is different from the first exemplary embodiment in that the pump includes a pressure sensor 90 in the primary pump chamber 27 . Descriptions of constituent elements common to the first exemplary embodiment will be omitted.
  • FIG. 5 is a vertical cross-sectional schematic of the pump according to the third exemplary embodiment of the present invention
  • FIG. 6 is a schematic of the driving circuit of the pump according to the third exemplary embodiment.
  • two-stepped concave portion 35 is formed in an inside top wall of the primary pump chamber 27 .
  • the pressure sensor 90 made of the same material as the aforementioned plate-shaped piezoelectric element 71 is fixed to the step of the concave portion 35 toward the primary pump chamber 27 .
  • An electrode, not shown, is formed on the surface of the pressure sensor 90 .
  • the pressure sensor is connected to the pump driving control circuit 80 (see FIG. 6 ) to be described later.
  • the concave portion 35 has a gap so that the pressure sensor 90 does not come in contact with the wall when it is bent.
  • the driving circuit system of the pump 10 includes the laminated piezoelectric element 70 to drive the primary pump chamber diaphragm 60 , the plate-shaped piezoelectric element 71 to drive the secondary pump chamber diaphragm 45 , the pressure sensor 90 to detect the inside pressure of the primary pump chamber 27 , and the pump driving control circuit 80 to control the driving of the pump 10 .
  • the pump not including a check valve at the outflow passage 28 side of the primary pump chamber 27 has been constructed. But in the pump including the check valve and requiring the priming action, the similar advantages can be obtained.
  • the pressure sensor 90 is provided in the primary pump chamber 27 , it is possible to accurately detect the operation failure due to interfusion of the gas bubbles into the primary pump chamber 27 . Furthermore, in the third exemplary embodiment of the present invention, since the plate-shaped piezoelectric element 71 of the secondary pump chamber diaphragm 45 can be driven in synchronism with the primary pump chamber diaphragm 60 , it is possible to further enhance the suction efficiency of the primary pump chamber 27 , so that it is possible provide a higher-power pump.
  • the fourth exemplary embodiment basically has the technical spirit of the first exemplary embodiment, but is different from the first exemplary embodiment in that a pressurizing mechanism 150 is provided as a bubble exclusion unit in place of the secondary pump chamber 24 (see FIG. 1 ).
  • FIG. 7 is a vertical cross-sectional schematic of the pump according to the fourth exemplary embodiment of the present invention.
  • the pump 100 basically includes the cup-shaped case 50 to which the laminated piezoelectric element 70 is fixed, an inflow passage 121 to introduce the working fluid, an outflow passage 128 to discharge the working fluid, a pump case 120 having a pump chamber 127 , and a pressurizing mechanism 150 (surrounded with a broken line in the figure) to apply pressure to the pump chamber 127 .
  • one end of the laminated piezoelectric element 70 is fixed to an inside bottom portion thereof.
  • the diaphragm 60 is fixed to the edge portion of the case 50 and a top surface of the other end of the laminated piezoelectric element 70 .
  • a pump case 120 is airtightly fixed to the top surface of the diaphragm 60 .
  • the pump chamber 127 is formed in a space between the diaphragm 60 and the bottom of the pump case 120 .
  • the inflow passage 121 and the outflow passage 128 are formed toward the pump chamber 127 .
  • a check valve 122 as a fluid resistance element to open and close the inflow passage 121 is provided at a connection portion with the pump chamber 127 .
  • a part of the outer circumference of a cylindrical portion constituting the inflow passage 121 functions as an inlet connection tube 130 to be connected to an external tube, not shown.
  • the outflow passage 128 includes a narrow tube portion connected to the pump chamber 127 and a wide tube portion of which a sectional area is enlarged in the way, which are formed continuously.
  • the outer circumference of a cylindrical portion constituting the outflow passage 128 functions as an outlet connection tube 131 to be connected to an external tube, not shown.
  • tubes made of silicon rubber can be used as the external tubes.
  • the pressure sensor 90 as the pressure detecting section to detect the inside pressure of the pump chamber 127 is fixed to the inside top wall of the pump chamber 127 .
  • the pump 100 is provided with the pressurizing mechanism 150 surrounded with a broken line in the figure.
  • the pressurizing mechanism 150 includes a metallic bellows 151 , which is an elastic member, an actuator 170 formed out of a piezoelectric element as a volume varying mechanism of the bellows 151 , and an shutoff valve 140 to shut off the movement of the working fluid in the outflow passage 128 .
  • the bellows 151 is closely fixed to a side surface of the outlet connection tube 131 . Its opening portion 152 is connected to the flow passage 132 communicating with the outflow passage 128 .
  • a variable-volume chamber is formed inside the bellows 151 .
  • a pressure sensor 91 as the pressure detecting section to detect the inside pressure of the bellows 151 , is provided inside the bellows. The volume of the bellows 151 is varied by the actuator 170 .
  • an end of the actuator 170 opposite to the bellows 151 is fixed to the side of the inlet connection tube 130 .
  • the actuator is reciprocated by a driving section, not shown.
  • the actuator includes a pressing section 171 to compress the bellows 151 .
  • the pressing section is driven by the pump driving control circuit 180 (see FIG. 8 ).
  • the sectional area of the wide tube portion of the outflow passage 128 at a position connected to the bellows 151 is double the sectional area of the narrow tube portion. For this reason, the flow rate of the fluid passing through the flow passage 132 connected to the bellows 151 is decreased, so that the energy loss of the fluid during passing the flow passage can be reduced.
  • the flow passage extending from the opening portion of the pump chamber 127 to the connection with a pulsation absorbing device is defined as the inlet passage.
  • the pulsation absorbing device sufficiently reduces the variation in the inside pressure of the flow passage.
  • a flow passage made of material, such as silicon rubber, resin, thin metal, which can be easily deformed with the inside pressure, an accumulator connected to the flow passage, a composition flow passage to compose pressure variations having a plurality of different phases, etc. correspond to the pulsation absorbing device.
  • the flow passage extending from the opening portion of the pump chamber 127 to the end surface of the connection side of the silicon rubber tube in the inflow passage 121 , that is, the inflow passage 121 itself, is defined as the inlet passage.
  • the outlet passage is defined similarly to the inlet passage.
  • a flow passage extending from the opening portion of the pump chamber 127 to a connection portions with the pulsation absorbing device is defined as the outlet passage.
  • the outflow passage 128 extending from the opening portion of the pump chamber 127 to the connection portion with the bellows 151 is defined as the outlet passage.
  • the discharge mode refers to an operation mode in which the working fluid is allowed to flow out toward the downstream of the outflow passage 128 , and is performed in a case where the working fluid is filled in the pump chamber 127 and thus gas bubbles do not stay therein.
  • the shutoff valve 140 does not shut off the outflow passage 128 .
  • the pressing section 171 of the actuator 170 is separated from the bellows 151 , as shown in FIG. 7 .
  • the bellows 151 can be freely deformed elastically with the inside pressure.
  • the bellows 151 functions to reduce the pressure pulsation in the outflow passage 128 .
  • the internal state of the pump 100 according to the fourth exemplary embodiment when it is driven will be described.
  • the internal state of the pump 100 is similar to the above first exemplary embodiment (see FIG. 2 ), the description thereof is omitted.
  • features of the fourth exemplary embodiment will be described in detail.
  • the pump 100 causes a high pressure in the pump chamber 127 , thereby obtaining a high power.
  • the variation in volume (hereinafter, referred to as exclusion volume) of the pump chamber 127 generated due to the deformation of the diaphragm 60 is used to compress the gas bubbles during the time when the laminated piezoelectric element 70 turns to the state where it is most expanded from the state where it is most contracted, and thus does not contribute to increase the inside pressure of the pump chamber 127 , so that the pump cannot operate properly. For this reason, it is important to exclude the staying gas bubbles rapidly.
  • FIG. 8 is a schematic of the driving circuit of the pump 100 according to the fourth exemplary embodiment.
  • the bubble discharge mode refers to an operation mode to be performed when the gas bubbles stay in the pump chamber 127 .
  • the driving circuit system of the pump 100 includes the pressure sensor 90 (see FIG. 7 ) to detect the inside pressure of the pump chamber 127 , the pressure sensor 91 to detect the inside pressure of the bellows 151 , the pressurizing mechanism 150 , and a pump driving control circuit 180 to control them.
  • the pump driving control circuit 180 determines that gas bubbles stay in the pump chamber 127 . Then, the pump driving control circuit 180 gives an instruction to the pressurizing mechanism 150 . In response to the instruction, first, the shutoff valve 140 is switched not to shut off the outflow passage 128 . Next, the actuator 170 in FIG. 7 allows the pressing section 171 to extend left and to come in contact with the bellows 151 , and then compresses the bellows 151 in the left direction, so that the volume of the chamber formed out of the bellows 151 is largely reduced. As a result, the gas bubbles staying in the chamber formed out of the bellows 151 can be allowed to flow out to the downstream from the shutoff valve 140 .
  • the shutoff valve 140 shuts off the outflow passage 128 , and the actuator 170 allows the pressing section 171 to be contracted and separated from the bellows 151 . Since the bellows 151 is formed of an elastic member, it is recovered to the original state with its own elastic force. In this way, the working fluid is filled in the bellows 151 . Subsequently, the actuator 170 is allowed to compress the bellows 151 again. As a result, the pressure of the working fluid existing from the inside of the bellows 151 to the pump chamber 127 can be raised.
  • the volume of the gas bubbles staying in the pump chamber 127 is decreased through the pressing, and the volume of the gas bubbles can be made to be smaller enough than the exclusion volume.
  • the inside pressure of the pump chamber 127 is raised enough and the working fluid is discharged from the pump chamber 127 to the outflow passage 128 .
  • the gas bubbles staying in the pump chamber 127 flows in the bellows 151 with the flow of the working fluid in the pump chamber 127 .
  • the pump driving control circuit 180 includes a timer (not shown) to count the time when the laminated piezoelectric element 70 is driven after the shutoff valve 140 shuts off the outflow passage 128 . After a predetermined time interval, as a time interval enough to discharge the gas bubbles staying in the pump chamber 127 , is counted with the timer, the shutoff valve 140 releases the shutoff of the outflow passage 128 and the actuator 170 is contracted up to the position where it is separated from the bellows 151 . Thereafter, the bubble discharge mode is finished.
  • the inside pressure of the bellows 151 is raised due to the working fluid discharged from the pump chamber 127 .
  • the bellows is designed such that the deformation due to the pressure is suppressed within an allowable range of elastic deformation. In this way, by forming the variable-volume chamber out of an elastic member, the pressure can be made to be smoothly raised due to the introduction of the working fluid, so that it is possible to prevent destruction of the constituent elements of the pump 100 .
  • the pump driving control circuit 180 may be allowed to control the actuator 170 by using values detected by the pressure sensor 91 provided in the bellows 151 , so that it may be possible to suppress the inside pressure of the bellows 151 from being raised.
  • the pump may be constructed so that a relief valve is provided in the bellows 151 , and it is possible to surely suppress the inside pressure of the bellows 151 from being raised by opening the relief valve when the inside pressure of the bellows 151 is too high.
  • the pressurizing mechanism 150 to raise and maintain the pressure of the working fluid existing in the pump chamber 127 since the pressurizing mechanism 150 to raise and maintain the pressure of the working fluid existing in the pump chamber 127 is provided, it is possible to raise and maintain the pressure of the working fluid existing in the pump chamber 127 , when the gas bubbles stay in the pump chamber 127 , the inside pressure of the pump chamber 127 is reduced. Thus it is not possible to discharge the working fluid. As a result, the volume of the gas bubbles is decreased, so that it is possible to discharge the gas bubbles in the pump chamber by compressing the volume of the pump chamber 127 through the operation of the diaphragm 60 .
  • the pressurizing mechanism 150 presses the bellows 151 . But since the variable-volume chamber of the bellows 151 communicates with the outflow passage 128 , it is possible to simply generate a high pressure in the pump chamber 127 communicating with the outflow passage 128 .
  • variable-volume chamber out of an elastic member
  • the increase in pressure due to introduction of the working fluid into the variable-volume chamber is smoothed, so that it is possible to prevent the constituent elements of the pump from being damaged due to the pressure.
  • the variable-volume chamber can be allowed to have a function of reducing the pressure pulsation in the outlet passage. As a result, it is possible to reduce or prevent the pump ability from be varied due to influence of the external tube connected to the outlet passage.
  • the detected value of the pressure sensor 90 in the pump chamber 127 may be checked, for example, by arbitrarily setting the time interval to be counted by the timer of the pump driving control circuit 180 and allowing the pump to operate in the discharge mode after the bubble discharge mode is finished.
  • the operation of the bubble discharge mode since the operation of the bubble discharge mode is executed when it is determined using the pressure sensor 90 in the pump chamber 127 that the gas bubbles stay, the operation of the bubble discharge mode is not executed wastefully. But the operation of the bubble discharge mode may be executed at proper time intervals.
  • the pressure sensor 90 can be omitted, so that it is possible to simplify the structure.
  • the inflow passage 121 and the outflow passage 128 are connected to the external tubes, it is possible to raise and maintain the inside pressure of the pump chamber 127 by pressing the bellows 151 with the actuator 170 without the shutoff valve 140 , thereby obtaining the same advantage.
  • the actuator 170 is provided to press the bellows 151 , the same advantage can be obtained, even when a display device through which a user can view an output of the pressure sensor 91 is provided and the user manipulates the shutoff valve 140 to press the bellows 151 .
  • the pressure sensor 90 has been provided as the pressure detecting device for the pump chamber in the pump chamber 127 , but a different device may be employed.
  • the inside pressure of the pump chamber 127 may be calculated by measuring the deformation of the diaphragm 60 with a strain gauge or a displacement sensor.
  • the inside pressure of the pump chamber 127 may be calculated by measuring the deformation of the case 50 with a strain gauge.
  • the inside pressure of the pump chamber 127 may be calculated by measuring the deformation of the opening and closing member in a state where the check valve 122 is closed, with a strain gauge or a displacement sensor.
  • the inside pressure of the pump chamber 127 may be calculated by measuring current to drive the laminated piezoelectric element 70 with a current sensor. Furthermore, by providing a strain gauge in the laminated piezoelectric element 70 , the inside pressure of the pump chamber 127 may be calculated on the basis of a voltage applied to the laminated piezoelectric element 70 and the measured value by the strain gauge. At that time, any type of strain gauge which detects the quantity of deformation by using variation in resistance, variation in capacitance, or variation in voltage may be used as the strain gauge. As the inside pressure detecting device of the bellows 151 , a structure of calculating the pressure by detecting the deformation of the bellows 151 with a strain gauge may used.
  • a piezoelectric element has been employed as the actuator 170 .
  • an electromagnetic type actuator, a shape-memory alloy type actuator, etc. in addition to the piezoelectric element may be employed. Since the shape-memory alloy type actuator can realize a large quantity of deformation with a simple structure, it is preferable.
  • the elastic member forming the variable-volume chamber may be made of rubber or resin material. But the elastic member made of metal is specifically preferable because it can reduce or prevent vaporization of the working fluid. Furthermore, the variable-volume chamber may have a film shape or a diaphragm shape. But since the bellows shape described in the fourth exemplary embodiment can cause a large quantity of deformation and the laminated piezoelectric element 70 can be driven in the bubble discharge mode continuously for a long time, it is preferable in that the gas bubbles can be easily discharged.
  • the pump according to the fifth exemplary embodiment has the basic structure similar to the fourth exemplary embodiment (see FIG. 7 ), but is different from the fourth exemplary embodiment in that the pump has a structure of switching between a first mode where the working fluid flowing out of the pump chamber 127 is introduced into the chamber formed out of the bellows 151 and a second mode where the chamber formed out of the bellows 151 is shut off from the flow of the working fluid flowing out of the pump chamber 127 . Therefore, the difference will be paid attention to.
  • the same functional members are denoted by the same reference numerals as the fourth exemplary embodiment (see FIG. 7 ).
  • FIG. 9 shows a vertical cross-sectional schematic of the pump 100 according to the fifth exemplary embodiment.
  • the pressurizing mechanism 150 surrounded with a broken line is provided in the outflow passage 128 .
  • the pressurizing mechanism 150 includes the metallic bellows 151 formed of an elastic member, and a switching valve 190 (surrounded with two-dot chain line in the drawing) which is a passage switching device.
  • the switching valve 190 includes a switching valve 182 to open and close the flow passage 132 communicating with the outflow passage 128 at the opening portion 152 of the chamber formed out of the bellows 151 , and a switching valve 183 to open and close the outflow passage 128 .
  • the switching valve 190 functions as switching a first connection state where, the outflow passage 128 extending from the pump chamber 127 to the switching valve 182 , and the outflow passage 128 at the downstream side thereof, communicates with each other, by opening the switching valve 183 , and the chamber formed out of the bellows 151 is shut off from the outflow passage 128 by closing the switching valve 182 , and a second connection state where, the outflow passage 128 extending from the pump chamber 127 to the switching valve 182 and the chamber formed out of the bellows 151 communicate with each other, and the outflow passage 128 at the more downstream side than the switch valve 183 , is shut off by closing the switching valve 183 .
  • the sectional area of the outflow passage 128 at the position at which the switching valve 183 is arranged is double the sectional area of the narrow flow passage portion of the outflow passage 128 connected to the pump chamber 127 .
  • the reason has been described in the fourth exemplary embodiment.
  • the pressure sensor 91 as an inside pressure detecting device of the bellows to detect the pressure of the chamber formed out of the bellows 151 , is provided in the bellows 151 .
  • definitions of the inlet passage and the outlet passage, and relations of the inertance values in the fifth exemplary embodiment are similar to the fourth exemplary embodiment.
  • the switching valve 190 is switched into the first connection state to allow the working fluid to flow out toward the downstream of the outflow passage 128 .
  • the pressure waveform in the pump chamber 127 when the laminated piezoelectric element 70 is driven is similar to the first exemplary embodiment (see FIG. 2 ).
  • the pump chamber has a very high inside pressure, it is possible to cope with a high load pressure.
  • the bubble discharge mode which is executed when the gas bubbles stay in the pump chamber.
  • the pump driving control circuit determines that the gas bubbles stay in the pump chamber 127 , the pump driving control circuit gives an instruction to the switching valve 190 .
  • the switching valve 190 is switched into the second connection state from the first connection state.
  • the pump chamber 127 is almost pressurized up to the above pressure. In this way, by forming the variable-volume chamber out of an elastic member, it is possible to apply the pressure only with the elastic force of the elastic member.
  • the pump driving control circuit includes a timer (not shown) to count the time interval when the laminated piezoelectric element 70 is driven after the switching valve 190 is switched into the second connection state, a predetermined time interval is counted as the time interval enough to discharge the gas bubbles staying in the pump chamber 127 by using the timer, the switching valve 190 is then switched into the first connection state, and then the bubble discharge mode is finished.
  • the inside pressure of the bellows 151 is raised by the working fluid discharged from the pump chamber 127 .
  • the bellows is designed so that the deformation due to the inside pressure is suppressed within an allowable range for elastic deformation.
  • the pump may be constructed so that a relief valve, not shown, is provided in the bellows 151 , and it is possible to suppress the inside pressure of the bellows 151 from being raised by opening the relief valve when the inside pressure of the bellows 151 is too high.
  • a relief valve not shown
  • a bellows pressing mode which is performed to maintain the inside pressure of the bellows 151 to about one atmosphere or more in a gauge pressure and preferably a value between about one atmosphere and five atmospheres, will be described with reference to FIG. 8 .
  • the inside pressure of the bellows 151 is detected by the pressure sensor 91 provided in the bellows 151 .
  • an instruction is given to the pressurizing mechanism 150 from the pump driving control circuit 180 , so that the switching valve 190 is switched to the second connection state.
  • the diaphragm 60 is driven by the laminated piezoelectric element 70 , so that the fluid is allowed to flow out of the pump chamber 127 to the outflow passage 128 , similarly to the discharge mode.
  • the working fluid flows in the bellows 151 through the switching valve 182 , so that the inside of the chamber formed out of the bellows 151 is compressed.
  • the pump driving control circuit 180 confirms on the basis of the detected value of the pressure sensor 91 that the inside pressure of the bellows 151 reaches about one atmosphere or more in a gauge pressure and preferably a value between about one atmosphere and five atmospheres, an instruction is given to the pressurizing mechanism 150 from the pump driving control circuit 180 , the switching valve 190 is thus switched to the first connection state, and then the bellows pressing mode is finished.
  • the inside of the bellows 151 can be always maintained to the set pressure, so that it is possible to wait for the bubble discharge mode.
  • the switching valve 190 includes two valves. But an integrated three-way valve, etc. may be used. Since a hole (not shown in the figures), which can be airtightly closed, is provided in the bellows 151 , it is possible to discharge the gas bubbles through the hole when too many gas bubbles are gathered in the bellows 151 .
  • the bellows pressing mode may be performed every predetermined time interval without providing the pressure sensor 91 in the bellows.
  • the laminated piezoelectric element 70 by converting the amount of leakage from the time until the current bellows pressing mode is started after the previous bellows pressing mode is finished, it is possible to drive the laminated piezoelectric element 70 for the time required to allow the working fluid having the same volume as the amount of leakage to flow into the bellows 151 from the pump chamber 127 .
  • the bellows pressing mode may be performed every predetermined time interval.
  • the relief valve is opened.
  • the working fluid is leaked, so that it is possible to maintain the inside of the bellows 151 at a constant pressure.
  • the pressure sensors described in the fourth exemplary embodiment can be similarly used as the pressure sensor 90 in the pump chamber 127 to detect the inside pressure of the pump chamber 127 and the pressure sensor 91 in the bellows 151 .
  • the pressurizing mechanism 150 is provided with the passage switching device to switch between the first mode in which the working fluid flowing out of the pump chamber 127 is introduced into the chamber of the bellows 151 and the second mode in which the chamber of the bellows 151 is shut off from the flow of the working fluid flowing out of the pump chamber 127 .
  • the pressurizing mechanism 150 is provided with the passage switching device to switch between the first mode in which the working fluid flowing out of the pump chamber 127 is introduced into the chamber of the bellows 151 and the second mode in which the chamber of the bellows 151 is shut off from the flow of the working fluid flowing out of the pump chamber 127 .
  • the pressure sensor 91 to detect the inside pressure of the variable-volume chamber is provided, it is possible to control the inside pressure of the variable-volume chamber within a proper pressure range. Furthermore, since the pressure sensor 90 is provided in the pump chamber 127 , it is possible to determine whether the gas bubbles stay in the pump chamber 127 .
  • the pressure applied from the pressurizing mechanism 150 is set to a value between about one atmosphere and five atmospheres in a gauge pressure, it is possible to reduce the volume of the gas bubbles staying in the pump chamber as small as possible to discharge, without damaging the constituent components of the pump due to the pressure.
  • the sixth exemplary embodiment of the present invention has a basic structure similar to the above fourth exemplary embodiment except for the pressurizing mechanism, and thus differences therebetween will be described in detail.
  • the pump according to the sixth exemplary embodiment is used without connecting an external tube to the outflow passage 128 , has a structure not requiring the switching valve (see FIGS. 7 and 9 ) described in the fourth and fifth exemplary embodiments, and is characterized in that the pressurizing mechanism 150 is provided detachably from the outflow passage 128 .
  • FIG. 10 shows a vertical cross-sectional schematic of the independent pressurizing mechanism according to the sixth exemplary embodiment.
  • the pressurizing mechanism 150 includes the bellows 151 and a valve case 153 to which the bellows 151 is fixed and receives a valve 156 .
  • variable-volume chamber in which the working fluid stay and an opening portion 152 are formed in the bellows 151 which is closely fixed to an end of the valve case 153 .
  • the valve case 153 includes the opening portion 152 communicating with the bellows 151 , an entry hole 155 into which the outlet connection tube 131 (see FIG. 11 ) of the pump 100 is inserted, a valve fitting hole 154 which communicates with the opening portion 152 and an entry hole 155 and to which the valve 156 is fitted, and a rod inserting hole 160 into which a rod 159 of the valve 156 is inserted.
  • a seal member 165 to prevent the working fluid from being leaked from the connected portion of the outlet connection tube 131 and the entry hole 155 is fitted into an intermediate portion of the entry hole 155 .
  • the valve 156 is connected to the rod 159 with the rod inserting hole 160 therebetween and a washer 157 to fix the rod 159 .
  • Through-holes 158 through which the working fluid passes are formed in the washer 157 .
  • a coil spring 161 to apply force to the valve 156 in order to seal the rod inserting hole 160 is provided between the washer 157 and the inside wall of the entry hole 155 .
  • variable-volume chamber of the bellows 151 is compressed within a range of about one atmosphere to five atmospheres in a gauge pressure by means of the elastic force of the bellows 151 , similarly to the fourth and fifth exemplary embodiment.
  • FIG. 11 is a partially vertical cross-sectional schematic illustrating a state where the above pressurizing mechanism 150 is fitted into the outlet connection tube 131 of the pump 100 .
  • the entry hole 155 of the pressurizing mechanism 150 is inserted into the outlet connection tube 131 .
  • the front end portion of the outlet connection tube 131 comes in contact with the washer 157 and compresses the coil spring 161 , so that the valve 156 is moved to a position to open the rod inserting hole 160 .
  • the outflow passage 128 and the chamber surrounded with the bellows 151 communicates with each other, so that the working fluid can flow through the through-holes 158 therebetween.
  • the pressurizing mechanism 150 is separated from the outflow passage 128 to discharge the working fluid from the outflow passage 128 .
  • a principle of discharging the working fluid to the outflow passage 128 is similar to that of the first exemplary embodiment. Therefore, when the gas bubbles stay in the pump chamber 127 , increase in pressure of the pump chamber is hindered and the pump ability is thus deteriorated largely, so that it is important to rapidly exclude the gas bubbles.
  • the staying gas bubbles can be discharged into the bellows 151 from the outflow passage 128 , as described in the fourth and fifth exemplary embodiments.
  • a lock mechanism to prevent the connection of the outflow passage 128 and the bellows 151 from going amiss may be provided.
  • the inside pressure of the bellows may be suppressed from being raised by providing a relief valve in the bellows 151 . Furthermore, by providing a hole that can be airtightly closed in the bellows 151 , the gas bubbles staying in the bellows can be discharged.
  • the pressurizing mechanism is freely detachable, when the pressurizing mechanism is fitted into the outlet passage, the outlet passage and the pressurizing mechanism communicate with each other.
  • the inside pressure of the variable-volume chamber is raised, thereby discharging the gas bubbles in the pump chamber.
  • the gas bubbles do not stay in the pump chamber, by separating the pressurizing mechanism, it is possible to realize a small and light pump.
  • the seventh exemplary embodiment has the same basic structure and discharge operation of working fluid as the first to sixth exemplary embodiments described above, but is different from them in that a heating section is provided as the bubble excluding device of the pump chamber.
  • FIG. 12 shows a vertical cross-section of the pump 200 according to the seventh exemplary embodiment.
  • the pump 200 includes a cup-shaped case 50 to which a laminated piezoelectric element 70 is fixed, an inflow passage 221 to introduce a working fluid, an outflow passage 228 to discharge the working fluid, a pump case 220 having a pump chamber 227 , and a ring-shaped heater 212 provided in the pump chamber 227 .
  • one end portion of the laminated piezoelectric element 70 is fixed to the inside bottom portion, and a diaphragm 60 is fixed to both of the edge portion of the case 50 and the other end portion of the laminated piezoelectric element 70 .
  • the pump case 220 is airtightly fixed to the top surface of the diaphragm 60 .
  • the pump chamber 227 is formed in a space between the diaphragm 60 and the bottom portion of the pump case 220 .
  • the inflow passage 221 and the outflow passage 228 are formed toward the pump chamber 227 .
  • a check valve 222 as a fluid resistance element to open and close the inflow passage 221 is provided at a connecting portion with the pump chamber 127 .
  • a part of the outer circumference of a cylindrical portion constituting the inflow passage 221 functions as an inlet connection tube 230 to be connected to an external tube, not shown.
  • a part of the outer circumference of a cylindrical portion constituting the outflow passage 228 functions as an outlet connection tube 231 to be connected to an external tube, not shown.
  • the external tubes not shown, for example, tubes made of silicon rubber can be used.
  • the inflow passage 221 itself is defined as an inlet passage.
  • the outflow passage 228 itself is defined as an outlet passage.
  • the resultant inertance value of the inlet passage side is set to be smaller than the inertance value of the outlet passage side.
  • a ring-shaped heater 212 is fixed to the outer circumferential comer portion of the inside top wall of the pump chamber 227 .
  • the heater 212 is airtightly inserted and fixed to the comer portion of the top wall of the pump chamber 227 , so that the heater is not protruded from the top wall surface of the pump chamber 227 toward the pump chamber.
  • FIG. 13 is a schematic of the pump case 220 shown in FIG. 12 as seen from the pump chamber side.
  • the heater 212 is arranged at a position in the comer portion of the pump chamber 227 where gas bubbles easily stay.
  • the heater 212 is formed by fixing a resistance member to a ceramics substrate of alumina, etc., and then coating an insulating film thereon.
  • Various members may be used as the resistance member. But members having a high melting point, specifically, platinum or platinum alloy, may be used.
  • a lead wire to supply power to the heater 212 is drawn out through the pump case 220 .
  • the inside of the pump chamber 227 is provided with a pressure sensor 90 , not shown (see FIG. 15 ).
  • the heater 212 is formed as a thin plate having a circular plate shape, and is fixed to a wide range of the top wall surface of the pump chamber 227 other than the circumferential portion of the inflow passage 221 and outflow passage 228 .
  • the heater 212 is inserted into the top wall of the pump chamber 227 so that it is not protruded from the top wall surface.
  • the discharge mode is a mode in which power is not supplied to the heater 212 and a voltage is applied only to the piezoelectric element 70 . Since the discharge mode has been described in the first to sixth exemplary embodiments described above, the description thereof will be omitted. At that time, as described above, when the gas bubbles stay in the pump chamber 227 , the inside pressure of the pump chamber is decreased and the pump ability is deteriorated, so that a bubble discharge mode is performed.
  • FIG. 15 is a schematic of a driving circuit system of the pump 200 .
  • the driving circuit system of the pump 200 includes a pressure sensor 90 as a pressure detecting device in the pump chamber 227 , a heater 212 , a power distribution circuit 265 to control the heater 212 , and a pump driving control circuit 280 to control the driving of the pump 200 .
  • the pump driving control circuit 280 determines that the gas bubbles stay in the pump chamber 227 , and thus switches the driving mode to the bubble discharge mode from the discharge mode. Then, the pump driving control circuit 280 sends a signal to the power distribution circuit 265 . Then the power distribution circuit 265 starts the power distribution to the heater 212 in response to the signal.
  • the heater 212 Since the heater 212 is arranged at the comer portion in which the flow is stagnated and the gas bubbles easily stay as described above, the staying gas bubbles existing in the vicinity thereof are heated by the heater 212 , so that it is possible to expand the volume of the gas bubbles. As a result, if the size of the staying gas bubbles is not received in the stagnated area completely, the staying gas bubbles are moved along the flow inside the pump chamber 227 due to the driving of the diaphragm 60 and thus can be discharged out of the outflow passage 128 .
  • the bubble discharge mode is set to be finished after a predetermined time interval.
  • the power distribution circuit 265 to sequentially switch the power distributions to the respective heaters with time, the distributed current can be reduced without change of the heat quantity of the heaters supplied with electricity, so that the power distribution circuit 265 can be miniaturized.
  • the gas bubbles due to the phase change may be generated from the respective surface portions of the heaters 212 .
  • the working fluid corresponding to the volume of the generated gas bubbles is discharged to the outflow passage 228 .
  • the working fluid having an amount corresponding to the volume of the discharged working fluid is introduced into the pump chamber 227 through the check valve 222 from the inflow passage 221 .
  • FIG. 16 shows a modified example of the heater 212 .
  • the heater 212 includes two of a heater 213 arranged at the inflow passage 221 side and a heater 214 arranged at the outflow passage 228 side.
  • the phases of the distributed current to the respective heaters are deviated by using the power distribution circuit 265 (see FIG. 15 ).
  • the inside pressure of the gas bubbles generated through the film boiling on the surface of one heater exceeds the maximum value
  • the inside pressure of the gas bubbles generated through the film boiling on the surface of the other heater reaches the maximum value.
  • the heater 213 close to and the heater 214 far from the opening portion of the pump chamber 227 of the outflow passage 228 are provided, the power distribution to the far heater 214 is first started, and the power distribution to the heater 213 is started later, so that the flow from the comer portion of the pump chamber 227 toward the outflow passage 228 can be easily generated.
  • the number of heaters 212 may be two or more.
  • the diaphragm 60 may have any one of the stopped state and the driven state. But it is preferable that the diaphragm 60 is driven, so that the flow inside the pump chamber becomes complex and thus the staying gas bubbles can be easily excluded.
  • the pump driving control circuit 280 and the power distribution circuit 265 may be controlled so that the heater 212 is allowed to emit heat in a pulse shape by performing the power distribution to the heater 212 using a pulse current.
  • the diaphragm 60 is driven in a direction in which the volume of the pump chamber 227 is reduced in synchronism with the heat emitting.
  • the detected value by the pressure sensor 91 may be checked by driving the pump in the discharge mode after the bubble discharge mode is finished, so that it is possible to repeat the driving of the bubble discharge mode until the staying gas bubbles are discharged.
  • the inside pressure of the pump chamber 227 is raised by providing the heater 212 inside the pump chamber 227 and thus the volume of the gas bubbles is compressed, it is possible to discharge the gas bubbles in the pump chamber 227 .
  • the heater 212 is fitted into the wall of the pump chamber 227 so that the heater is not protruded from the wall, and the heater is arranged at least at the comer portion of the pump chamber 227 , the gas bubbles can be prevented from staying in a protruded portion in which the gas bubbles is easily stagnated. It is also possible to discharge the staying gas bubbles at the comer portion of the pump chamber 227 .
  • the pressure sensor 90 is provided in the pump chamber 227 , it is possible to determine whether the gas bubbles stay in the pump chamber 227 , thereby discharge the gas bubbles in the pump chamber 227 as described above.
  • the heater 212 emits heat in a pulse shape and the diaphragm 60 is driven in synchronism with the pulse, it is possible to effectively discharge the gas bubbles staying in the pump chamber 227 while reducing the energy consumption of the heater 212 .
  • the heating process to generate the heat quantity with which the working fluid in contact with the heater 212 changes its phase
  • the gas bubbles due to the change of phase is generated in the pump chamber 227 , so that the complex and non-stagnated flow flowing toward the outflow passage 228 can be caused in the pump chamber 227 .
  • the bubble discharge mode is performed when it is determined by the pressure sensor 91 that the gas bubbles stay, the bubble discharge mode is not performed wastefully. But the bubble discharge mode may be performed every predetermined time interval. In this case, since the pressure sensor 91 can be omitted, it is possible to simplify the structure.
  • the construction that the pressure sensor as the pressure detecting device for the pump chamber is provided in the pump chamber 227 has been described. But different constructions may be employed. In one different construction, for example, the inside pressure of the pump chamber 227 may be calculated by measuring the deformation of the diaphragm 60 with a strain gauge or a displacement sensor. Further, the inside pressure of the pump chamber 227 may be calculated by measuring the deformation of the valve member in a state where the check valve 222 is closed, with a strain gauge or a displacement sensor. Furthermore, the inside pressure of the pump chamber 227 may be calculated by measuring current to drive the piezoelectric element 70 with a current sensor.
  • the inside pressure of the pump chamber 227 may be calculated on the basis of the voltage applied to the piezoelectric element 70 and the measured value by the strain gauge.
  • any type of strain gauges that detect the quantity of deformation by using variation in resistance, variation in capacitance, or variation in voltage may be used as the strain gauge.
  • the shape of the diaphragm 60 is not limited to the circular shape.
  • the check valve 222 is not limited to the passive valve which performs the opening and closing due to the pressure difference of the fluid, but an active valve which can control the opening and closing with different forces may be used as the check valve.
  • the present invention is not limited to the above exemplary embodiments, but the present invention includes modifications and enhancements.
  • the resultant inertance value of the inlet passage side is smaller than the resultant inertance value of the outlet passage side, and the heater 212 as the bubble discharging device is employed in the small high-pressure pump having an inertia effect of the working fluid.
  • the bubble discharge device may be employed, for example, in a pump using a unimorph type diaphragm shown in FIG. 17 .
  • FIG. 17 is a vertical cross-sectional schematic of the pump employing the unimorph type diaphragm.
  • the pump 200 includes a unimorph type diaphragm 260 as a diaphragm, and check valves 222 , 242 as the fluid resistance elements provided in both of the inflow passage 221 and the outflow passage 228 .
  • the diaphragm 260 is airtightly fixed to the edge portion of the cup-shaped case 250 .
  • the plate-shaped piezoelectric element 71 is fixed to the surface of the diaphragm 260 facing the case 250 .
  • the pump case 220 is airtightly fixed to the top of the diaphragm 260 , and the pump chamber 227 is formed between the diaphragm 260 and the pump case 220 .
  • the inflow passage 221 and the outflow passage 228 communicate with the pump chamber 227 .
  • the check valve 222 as the fluid resistance element, is provided in the inflow passage 221 .
  • the check valve 242 as the fluid resistance element, is provided in the outflow passage 228 .
  • the plane-shaped heater 212 as the heating section, is provided on the top wall surface constituting the pump chamber 227 of the pump case 220 .
  • the heater 212 is airtightly fitted into the pump case 220 , so that the heater is not protruded from the pump case 220 toward the pump chamber.
  • the shape and material of the heater 212 , and the position in which the heater is fitted into the pump case 220 are similar to the seventh exemplary embodiment and the modified example of the seventh exemplary embodiment. Thus descriptions thereof will be omitted.
  • the diaphragm 260 is deformed to have a convex surface toward the pump chamber 227 through the diametrical deformation of the plate-shaped piezoelectric element 71 . If the application of voltage is stopped, the diaphragm is restored to the original shape.
  • the check valves 222 and 242 close the flow passage, the diaphragm 260 is deformed in the direction in which the volume of the pump chamber 227 is decreased by using the deformation of the diaphragm 226 , thereby pressing the liquid inside the pump chamber 227 . If the inside pressure of the pump chamber 227 becomes higher than the downstream pressure of the check valve 242 , the check valve 222 is opened. Thus the liquid is discharged to the outflow passage 228 .
  • the check valve 242 is first closed. If the inside pressure of the pump chamber 227 becomes lower than the upstream pressure of the check valve 222 , the check valve 222 is opened, so that the liquid is introduced into the pump chamber 227 from the inflow passage 221 . By repeating the above actions, the working fluid is transferred.
  • the heater 212 as the bubble discharge device in the pump having the above structure, it is possible to allow the gas bubbles inside the pump chamber to flow out, and to suitably maintain the inside pressure of the pump chamber, so that it is possible to secure the amount of working fluid to be discharged.
  • the diaphragms 60 , 45 have a circular shape, but the shape is not limited to the circular shape.
  • the check valves 41 , 42 are not limited to the passive valves that perform the opening and closing process due to the pressure difference of the fluid, but active valves that can control the opening and closing process with different forces may be used as the check valves.
  • any element may be used as the piezoelectric element to drive the diaphragm 60 , only if it can be contracted and expanded.
  • the bubble discharging device since the bubble discharging device is provided, it is possible to provide a pump capable of discharging the gas bubbles and thus maintaining a discharging ability thereof, even when the gas bubbles stay in the pump chamber.
  • the pump according to aspects of the present invention can be applied to various industries requiring a small liquid transfer pump.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Reciprocating Pumps (AREA)
  • Details Of Reciprocating Pumps (AREA)
US10/866,119 2003-06-17 2004-06-14 Pump Abandoned US20050019180A1 (en)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
JP2003172106 2003-06-17
JP2003-172106 2003-06-17
JP2003290659 2003-08-08
JP2003-290659 2003-08-08
JP2003-348424 2003-10-07
JP2003348424 2003-10-07
JP2004-084638 2004-03-23
JP2004084638A JP4678135B2 (ja) 2003-06-17 2004-03-23 ポンプ

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US20050019180A1 true US20050019180A1 (en) 2005-01-27

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US10/866,119 Abandoned US20050019180A1 (en) 2003-06-17 2004-06-14 Pump

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US (1) US20050019180A1 (fr)
EP (1) EP1489306B1 (fr)
JP (1) JP4678135B2 (fr)
CN (1) CN100398821C (fr)
DE (1) DE602004006802T2 (fr)

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US20060092236A1 (en) * 2004-11-04 2006-05-04 Kye-Si Kwon Piezoelectric inkjet printhead having a unidirectional shutter
US20090010779A1 (en) * 2006-03-22 2009-01-08 Murata Manufacturing Co., Ltd. Piezoelectric Micropump
US20090162224A1 (en) * 2005-11-09 2009-06-25 Masanori Wakabayashi Pump using unimorph diaphragm
US20100021322A1 (en) * 2006-07-25 2010-01-28 Panasonic Electric Works Co., Ltd. Diaphragm pump
US20100054960A1 (en) * 2008-08-27 2010-03-04 Seiko Epson Corporation Pulsation generating mechanism, connecting flow channel tube, and fluid ejecting apparatus
US20100111726A1 (en) * 2008-10-31 2010-05-06 Fu Lung-Ming Electromagnetic Micro-pump
US20100139413A1 (en) * 2007-07-02 2010-06-10 Wolfram Herrmann Strain sensor and corresponding sensor arrangement
US20110006127A1 (en) * 2009-07-10 2011-01-13 Seiko Epson Corporation Pulsating flow generating apparatus and method of controlling pulsating flow generating apparatus
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US20130064683A1 (en) * 2011-09-13 2013-03-14 Seiko Epson Corporation Liquid feed pump and circulation pump
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JP2013189889A (ja) * 2012-03-13 2013-09-26 Seiko Epson Corp 流体循環装置および流体循環装置を用いた医療機器
US20130272898A1 (en) * 2012-04-17 2013-10-17 Schlumberger Technology Corporation Instrumenting High Reliability Electric Submersible Pumps
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US20150104332A1 (en) * 2012-03-20 2015-04-16 Aalto University Foundation Adaptive hydraulic pressure generator
US9057367B2 (en) 2010-09-21 2015-06-16 Seiko Epson Corporation Cooling device and projector
US9097244B2 (en) 2011-08-30 2015-08-04 Seiko Epson Corporation Fluid feeding pump, medical apparatus, and air bubble detection method for fluid feeding pump
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US20170172206A1 (en) * 2015-12-21 2017-06-22 Funai Electric Co., Ltd. Method and Apparatus for Metering and Vaporizing a Fluid
US20170173579A1 (en) * 2015-12-21 2017-06-22 Funai Electric Co., Ltd. Method and Apparatus for Metering and Vaporizing a Fluid
US20220205444A1 (en) * 2020-12-25 2022-06-30 Minebea Mitsumi Inc. Pump system, fluid supply device and pressure detection method
US11519404B2 (en) 2020-01-24 2022-12-06 Hamilton Sundstrand Corporation Determining a fatigue condition of a hydraulic system
US20230068420A1 (en) * 2021-08-17 2023-03-02 Facebook Technologies, Llc Fluid pump having a polyvinylidene fluoride membrane

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JP5407333B2 (ja) 2007-01-23 2014-02-05 日本電気株式会社 ダイヤフラムポンプ
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4309153A (en) * 1978-07-18 1982-01-05 Webasto-Werk W. Baier Gmbh & Co. Electromagnetic fuel delivery and metering pump
US5219278A (en) * 1989-11-10 1993-06-15 Westonbridge International, Ltd. Micropump with improved priming
US20020114716A1 (en) * 2001-02-21 2002-08-22 Seiko Epson Corporation Pump
US6485275B1 (en) * 1998-07-02 2002-11-26 Ngk Insulators, Ltd. Device for discharging raw material-fuel

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4960125U (fr) * 1972-09-12 1974-05-27
US4093403A (en) * 1976-09-15 1978-06-06 Outboard Marine Corporation Multistage fluid-actuated diaphragm pump with amplified suction capability
AU635262B2 (en) * 1989-05-11 1993-03-18 Bespak Plc Pump apparatus for biomedical use
EP0587912B1 (fr) * 1992-04-02 1997-09-10 Seiko Epson Corporation Microdispositif de regulation de debit de fluide, et procede de fabrication dudit dispositif
GB2266751A (en) * 1992-05-02 1993-11-10 Westonbridge Int Ltd Piezoelectric micropump excitation voltage control.
JPH06346838A (ja) * 1993-06-11 1994-12-20 Seiko Epson Corp ポンプのプライミング装置
JPH07195711A (ja) * 1993-12-28 1995-08-01 Canon Inc インクジェット記録装置
JPH09228964A (ja) * 1996-02-26 1997-09-02 Nikkiso Co Ltd 脱泡処理装置
JP2002322986A (ja) * 2001-02-21 2002-11-08 Seiko Epson Corp ポンプ
JP3692381B2 (ja) * 2001-08-29 2005-09-07 株式会社タクミナ ガス排出機構および往復動ポンプ

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4309153A (en) * 1978-07-18 1982-01-05 Webasto-Werk W. Baier Gmbh & Co. Electromagnetic fuel delivery and metering pump
US5219278A (en) * 1989-11-10 1993-06-15 Westonbridge International, Ltd. Micropump with improved priming
US6485275B1 (en) * 1998-07-02 2002-11-26 Ngk Insulators, Ltd. Device for discharging raw material-fuel
US20020114716A1 (en) * 2001-02-21 2002-08-22 Seiko Epson Corporation Pump

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US7549737B2 (en) * 2004-11-04 2009-06-23 Samsung Electronics Co., Ltd. Piezoelectric inkjet printhead having a unidirectional shutter
US20060092236A1 (en) * 2004-11-04 2006-05-04 Kye-Si Kwon Piezoelectric inkjet printhead having a unidirectional shutter
US8152491B2 (en) * 2005-11-09 2012-04-10 Nitto Kohki Co., Ltd. Pump using unimorph diaphragm
US20090162224A1 (en) * 2005-11-09 2009-06-25 Masanori Wakabayashi Pump using unimorph diaphragm
US20090010779A1 (en) * 2006-03-22 2009-01-08 Murata Manufacturing Co., Ltd. Piezoelectric Micropump
US8454327B2 (en) 2006-03-22 2013-06-04 Murata Manufacturing Co., Ltd. Piezoelectric micropump
US20100021322A1 (en) * 2006-07-25 2010-01-28 Panasonic Electric Works Co., Ltd. Diaphragm pump
US20100139413A1 (en) * 2007-07-02 2010-06-10 Wolfram Herrmann Strain sensor and corresponding sensor arrangement
US8511174B2 (en) * 2007-07-02 2013-08-20 Contitech Ag Strain sensor and corresponding sensor arrangement
US20100054960A1 (en) * 2008-08-27 2010-03-04 Seiko Epson Corporation Pulsation generating mechanism, connecting flow channel tube, and fluid ejecting apparatus
US20100111726A1 (en) * 2008-10-31 2010-05-06 Fu Lung-Ming Electromagnetic Micro-pump
US8147221B2 (en) * 2008-10-31 2012-04-03 National Pingtung University Of Science And Technology Electromagnetic micro-pump
CN101881266B (zh) * 2009-05-06 2012-08-22 研能科技股份有限公司 流体输送装置
US9097248B2 (en) 2009-07-10 2015-08-04 Seiko Epson Corporation Pulsating flow generating apparatus and method of controlling pulsating flow generating apparatus
US20110006127A1 (en) * 2009-07-10 2011-01-13 Seiko Epson Corporation Pulsating flow generating apparatus and method of controlling pulsating flow generating apparatus
US9057367B2 (en) 2010-09-21 2015-06-16 Seiko Epson Corporation Cooling device and projector
US9097244B2 (en) 2011-08-30 2015-08-04 Seiko Epson Corporation Fluid feeding pump, medical apparatus, and air bubble detection method for fluid feeding pump
US20130064683A1 (en) * 2011-09-13 2013-03-14 Seiko Epson Corporation Liquid feed pump and circulation pump
US9243619B2 (en) * 2011-09-13 2016-01-26 Seiko Epson Corporation Liquid feed pump and circulation pump with detection units to detect operating states of the pumps
JP2013189889A (ja) * 2012-03-13 2013-09-26 Seiko Epson Corp 流体循環装置および流体循環装置を用いた医療機器
US20130243616A1 (en) * 2012-03-15 2013-09-19 Seiko Epson Corporation Liquid circulating device and medical apparatus
US9970409B2 (en) * 2012-03-20 2018-05-15 Aalto University Foundation Adaptive hydraulic pressure generator
US20150104332A1 (en) * 2012-03-20 2015-04-16 Aalto University Foundation Adaptive hydraulic pressure generator
AU2013237295B2 (en) * 2012-03-20 2017-02-02 Aalto University Foundation Adaptive hydraulic pressure generator
US20130272898A1 (en) * 2012-04-17 2013-10-17 Schlumberger Technology Corporation Instrumenting High Reliability Electric Submersible Pumps
US20150060012A1 (en) * 2012-05-09 2015-03-05 Murata Manufacturing Co., Ltd. Cooling device and heating and colling apparatus
US9777974B2 (en) * 2012-05-09 2017-10-03 Murata Manufacturing Co., Ltd. Cooling device and heating and cooling apparatus
US20170198689A1 (en) * 2014-09-05 2017-07-13 Prominent Gmbh Displacement pump with fluid reservoir
CN106795873A (zh) * 2014-09-05 2017-05-31 卓越有限公司 带有流体贮存器的容积泵
US20170172206A1 (en) * 2015-12-21 2017-06-22 Funai Electric Co., Ltd. Method and Apparatus for Metering and Vaporizing a Fluid
US20170173579A1 (en) * 2015-12-21 2017-06-22 Funai Electric Co., Ltd. Method and Apparatus for Metering and Vaporizing a Fluid
US10334879B2 (en) * 2015-12-21 2019-07-02 Funai Electric Co., Ltd Method and apparatus for metering and vaporizing a fluid
US10344747B2 (en) * 2015-12-21 2019-07-09 Funai Electric Co., Ltd. Method and apparatus for metering and vaporizing a fluid
US11519404B2 (en) 2020-01-24 2022-12-06 Hamilton Sundstrand Corporation Determining a fatigue condition of a hydraulic system
US20220205444A1 (en) * 2020-12-25 2022-06-30 Minebea Mitsumi Inc. Pump system, fluid supply device and pressure detection method
US11754066B2 (en) * 2020-12-25 2023-09-12 Minebea Mitsumi Inc. Pump system, fluid supply device and pressure detection method
US20230068420A1 (en) * 2021-08-17 2023-03-02 Facebook Technologies, Llc Fluid pump having a polyvinylidene fluoride membrane

Also Published As

Publication number Publication date
JP2005133704A (ja) 2005-05-26
EP1489306A2 (fr) 2004-12-22
CN100398821C (zh) 2008-07-02
CN1573102A (zh) 2005-02-02
EP1489306B1 (fr) 2007-06-06
EP1489306A3 (fr) 2005-11-16
DE602004006802T2 (de) 2008-02-14
JP4678135B2 (ja) 2011-04-27
DE602004006802D1 (de) 2007-07-19

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