WO2010024199A1 - 積層型圧電素子およびこれを用いた噴射装置ならびに燃料噴射システム - Google Patents
積層型圧電素子およびこれを用いた噴射装置ならびに燃料噴射システム Download PDFInfo
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- WO2010024199A1 WO2010024199A1 PCT/JP2009/064637 JP2009064637W WO2010024199A1 WO 2010024199 A1 WO2010024199 A1 WO 2010024199A1 JP 2009064637 W JP2009064637 W JP 2009064637W WO 2010024199 A1 WO2010024199 A1 WO 2010024199A1
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- external electrode
- piezoelectric element
- multilayer piezoelectric
- laminate
- multilayer
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Images
Classifications
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/80—Constructional details
- H10N30/87—Electrodes or interconnections, e.g. leads or terminals
- H10N30/872—Interconnections, e.g. connection electrodes of multilayer piezoelectric or electrostrictive devices
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/01—Manufacture or treatment
- H10N30/06—Forming electrodes or interconnections, e.g. leads or terminals
- H10N30/063—Forming interconnections, e.g. connection electrodes of multilayered piezoelectric or electrostrictive parts
Definitions
- the present invention relates to a laminated piezoelectric element used for, for example, a driving element (piezoelectric actuator), a sensor element, a circuit element, and the like.
- the driving element include a fuel injection device for an automobile engine, a liquid injection device such as an inkjet, a precision positioning device such as an optical device, and a vibration prevention device.
- the sensor element include a combustion pressure sensor, a knock sensor, an acceleration sensor, a load sensor, an ultrasonic sensor, a pressure sensor, and a yaw rate sensor.
- Examples of the circuit element include a piezoelectric gyro, a piezoelectric switch, a piezoelectric transformer, and a piezoelectric breaker.
- a conductive paste including a conductive material such as silver and glass is used as an external electrode in a conventional laminated piezoelectric element.
- An external electrode is formed by applying this conductive paste to the side surface of the laminate and baking it.
- a conductive member for supplying a voltage to the external electrode is connected and fixed to the outside of the external electrode using solder, a conductive adhesive, or the like.
- the multilayer piezoelectric element is required to ensure a large amount of displacement under a large pressure at the same time as miniaturization is advanced. For this reason, it is required that a higher voltage can be applied and that the device can be used under severe conditions in which it is continuously driven for a long time.
- a part of the external electrode may be peeled off from the side surface of the multilayer body, and a voltage may not be supplied to the internal electrode layer of the multilayer body, and the multilayer piezoelectric element cannot maintain the initial displacement. There was a problem.
- the present invention has been made in view of the above problems, and even when used under severe conditions such as high voltage, high pressure, or continuous driving for a long time, the conductive member may peel off from the external electrode,
- An object of the present invention is to provide a multilayer piezoelectric element in which an electrode is not thermally destroyed.
- Another object of the present invention is to provide a multilayer piezoelectric element that can improve the deterioration of the displacement characteristics when used under severe conditions such as high voltage, high pressure or continuous driving for a long time.
- the first multilayer piezoelectric element according to the present invention is a laminate in which piezoelectric layers and internal electrode layers are alternately laminated, and is joined to a side surface of the laminate and electrically connected to the internal electrode layer.
- a multilayer piezoelectric element including an external electrode, wherein open pores are formed on a surface of the external electrode.
- the open pores are also formed at the edge of the external electrode.
- the open pores are formed in a region between the internal electrode layers adjacent in the stacking direction.
- a plurality of the open pores are formed in a region between the internal electrode layers adjacent in the stacking direction.
- the open pores are formed between metal particles constituting the external electrode.
- a conductive member is bonded to the external electrode.
- the second multilayer piezoelectric element according to the present invention is a laminate in which piezoelectric layers and internal electrode layers are alternately laminated, and is joined to a side surface of the laminate and electrically connected to the internal electrode layer.
- a multilayer piezoelectric element including an external electrode, wherein a plurality of holes are present in the external electrode so as to be biased toward the surface side.
- the pores exist in a surface layer portion of the external electrode.
- a glass component exists in the external electrode in a biased manner toward the bonding surface with the laminate.
- a plurality of the holes are formed also in a region where the glass component of the external electrode is unevenly distributed.
- the holes exist in a region between the internal electrode layers adjacent in the stacking direction.
- a glass layer made of the glass component is formed on the surface layer portion of the external electrode on the side of the joint surface with the laminate.
- the holes are also formed in the glass layer.
- the holes exist in a region between the internal electrode layers adjacent in the stacking direction.
- An ejection device includes a container having an ejection hole and any one of the multilayer piezoelectric elements according to the present invention, and a liquid stored in the container is ejected by driving the multilayer piezoelectric element. It is discharged from the hole.
- a fuel injection system includes a common rail that stores high-pressure fuel, an injection device according to the present invention that injects the high-pressure fuel stored in the common rail, and a pressure pump that supplies the high-pressure fuel to the common rail. And an injection control system for supplying a drive signal to the injection device.
- the conductive member for supplying voltage to the external electrode is replaced with solder or a conductive adhesive.
- solder or the conductive adhesive enters into the open pores on the surface of the external electrode when bonded to the external electrode using, etc.
- the bonding of the solder or the conductive adhesive to the external electrode is improved. Even when the bonding strength is improved and continuous driving is performed under high voltage and high pressure, it is possible to prevent the problem that the conductive member is peeled off from the external electrode.
- the surface of the external electrode is provided with a plurality of open pores, which increases the surface area of the external electrode and dissipates heat. Since the characteristics are improved, it is possible to prevent the problem that the external electrode is thermally destroyed due to heat generation.
- the stress generated in the external electrode due to the displacement accompanying the driving of the multilayer body can be absorbed and relaxed by a plurality of pores that are unevenly distributed on the surface side inside the external electrode, so that part of the external electrode can be peeled off from the side surface of the laminate, or in the external electrode and in the external electrode and internal electrode layer It is possible to prevent disconnection between the two.
- the plurality of holes are unevenly distributed on the surface side of the external electrode, without reducing the bonding strength on the bonding surface side with the laminate of the external electrode, and when driven continuously for a long time In the unlikely event that a crack occurs in the outer electrode from the side surface of the laminate, the vacancies unevenly distributed on the surface side act to prevent the crack from progressing, thus preventing the external electrode from being disconnected. can do.
- the multilayer piezoelectric element when the first multilayer piezoelectric element according to the present invention is provided as the multilayer piezoelectric element that discharges the liquid stored in the container from the ejection hole, the multilayer piezoelectric element is provided.
- the element it is possible to prevent the conductive member from peeling from the external electrode on the side surface of the laminated body, and it is possible to prevent the external electrode from being thermally destroyed due to heat generation. It can be performed stably.
- the second multilayer piezoelectric element according to the present invention when the second multilayer piezoelectric element according to the present invention is provided as the multilayer piezoelectric element for discharging the liquid stored in the container from the ejection hole, in the piezoelectric element, it is possible to prevent a part of the external electrode from being peeled off or disconnected from the side surface of the multilayer body, and it is possible to prevent the displacement characteristics of the multilayer body from being deteriorated. It can be performed stably over a long period of time.
- the injection device of the present invention since the injection device of the present invention is provided as an apparatus for injecting the high-pressure fuel stored in the common rail, the desired injection of the high-pressure fuel can be stably performed over a long period of time. it can.
- FIG. 3 is an enlarged cross-sectional view illustrating an example of the vicinity of a bonding interface between a multilayer body and an external electrode in the first multilayer piezoelectric element according to the present invention illustrated in FIG. 2.
- FIG. 2 It is an enlarged side view which shows the other example of embodiment of the 1st lamination type piezoelectric element which concerns on this invention.
- FIG. 2 It is an enlarged side view which shows the other example of embodiment of the 1st lamination type piezoelectric element which concerns on this invention.
- FIG. 3 shows the other example of embodiment of the 1st lamination type piezoelectric element which concerns on this invention.
- FIG. 3 is an enlarged cross-sectional view illustrating an example of the vicinity of a bonding interface between a multilayer body and an external electrode in the second multilayer piezoelectric element according to the present invention illustrated in FIG. 2.
- FIG. 1 is a perspective view showing an example of an embodiment of a first multilayer piezoelectric element according to the present invention
- FIG. 2 is a cross-sectional view parallel to the stacking direction of the multilayer piezoelectric element shown in FIG.
- FIG. 3 is an example of an enlarged cross-sectional view of the vicinity of the bonding interface between the multilayer body and the external electrode in the multilayer piezoelectric element shown in FIG.
- the multilayer piezoelectric element 1 As shown in FIG. 3, the multilayer piezoelectric element 1 according to the first embodiment is bonded to a laminated body 7 in which piezoelectric layers 3 and internal electrode layers 5 are alternately laminated, and to a side surface of the laminated body 7.
- the multilayer piezoelectric element 1 includes an external electrode 9 electrically connected to the internal electrode layer 5, and a plurality of open pores 2 ⁇ / b> A are formed on the surface of the external electrode 9.
- a conductive member such as a lead wire is connected and fixed to the external electrode 9 using solder or a conductive adhesive.
- the solder or the conductive adhesive enters the open pores 2A, so that the solder or the conductive adhesive can be bonded to the external electrode of the solder or the conductive adhesive. Bonding strength can be significantly improved.
- the heat dissipation of the external electrode 9 is improved by increasing the surface area of the external electrode 9 due to the plurality of open holes 2A. Even when the multilayer piezoelectric element 1 is driven at a high speed by flowing a large current, it is possible to prevent the external electrode 9 from being thermally destroyed by the heat generated by the external electrode 9.
- the multilayer piezoelectric element 1 when the multilayer piezoelectric element 1 is driven, tensile stress is applied to the external electrode 9, but a plurality of open pores 2 ⁇ / b> A formed on the surface of the external electrode 9 are opened or deformed according to the tensile stress applied to the external electrode 9. Since stress can be absorbed by doing so, it is possible to prevent the problem that the external electrode 9 is peeled off from the laminated body 7 even when the laminated piezoelectric element 1 is continuously driven at a high speed.
- the open pores 2 A are minute holes opened on the surface of the external electrode 9, and a plurality of open holes exist on the surface of the external electrode 9.
- the shape of the opening of the open pore 2A is not particularly limited, and may be a circular shape, an elliptical shape, a polygonal shape, or an indefinite shape.
- the size of the open pores 2A is such that when the thickness of the external electrode 9 is, for example, 10 to 50 ⁇ m, the size of the opening may be 0.1 to 10 ⁇ m in diameter and the depth is 0.1 to 10 ⁇ m. It may be the same size, larger or smaller.
- the plurality of open pores 2 ⁇ / b> A are distributed almost uniformly on the surface of the external electrode 9. It is preferable to be formed because the effect of the presence of the open pores 2 ⁇ / b> A can be similarly obtained over the entire external electrode 9. In addition, when the effect is needed locally, you may form so that it may be unevenly distributed in a desired location.
- the open pores 2A are formed on the surface of the external electrode 9 and externally. It is preferable that it is also formed at the edge of the electrode 9. This makes it possible to efficiently dissipate the heat transmitted from the central portion of the external electrode 9 to the edge portion, so that the heat dissipation of the external electrode 9 can be further improved.
- the open pores 2A are formed in the region between the internal electrode layers 5 adjacent to each other in the stacking direction. Preferably it is formed.
- the stress is applied to the joint portion between the internal electrode layer 5 and the external electrode 9 from the location where the open pores 2A are formed via solder or a conductive adhesive. Therefore, it is possible to prevent the joint portion between the internal electrode layer 5 and the external electrode 9 from being peeled off and disconnected.
- the open pores 2A are formed in the region between the internal electrode layers 5 adjacent to each other in the lamination direction. It is preferable that a plurality are formed. As a result, the bonding strength between the external electrode 9 and the conductive member by solder or conductive adhesive can be further improved in the region between the internal electrode layers 5 adjacent in the stacking direction, and the heat dissipation characteristics of the external electrode 9 can be improved. Further improvement can be achieved.
- a plurality of open pores 2A are formed in the region between the internal electrode layers 5 adjacent to each other in the stacking direction, in order to relieve the effect of relaxing the open pores 2A by the deformation of the laminate 7 by the expansion of the open electrodes By this, it can be greatly improved.
- An example in which a plurality of open pores 2A are formed in the region between the internal electrode layers 5 adjacent in the stacking direction is also shown in FIGS.
- a plurality of open pores 2A are formed on the surface of the external electrode 9 as shown in FIG. It is preferable that the void
- the effect that the open pores 2A reduce the stress generated in the external electrode 9 due to the expansion and contraction of the laminate 7 can be further improved by the presence of the pores 2B. This is because the stress can be absorbed by the holes 2 ⁇ / b> B deforming according to the stress generated in the external electrode 9.
- the air holes 2B are formed in the same manner as the open air holes 2A, but are not opened on the surface of the external electrode 9 and exist as closed air holes inside the external electrode 9.
- the shape and size of the air holes 2B are not particularly limited, and the cross-sectional shape may be a circular shape or an elliptical shape like the open air holes 2A, and may be a polygonal shape or an indefinite shape.
- the size of the hole 2B may be 0.1 to 10 ⁇ m in diameter when the thickness of the external electrode 9 is 10 to 50 ⁇ m, for example.
- the vacancies 2B are preferably formed to be distributed almost uniformly inside the external electrode 9 because the effect of the presence of the vacancies 2B over the entire external electrode 9 is obtained in the same manner. If necessary locally, it may be formed so as to be unevenly distributed at a necessary point.
- the open pores 2A are formed between the metal particles constituting the external electrode 9. Since the external electrode 9 is composed of metal particles and a glass component as described later, the open pores 2A formed on the surface are often formed of the metal particles and the glass component. By forming the open pores 2 between the particles, that is, by forming the open pores 2A as being surrounded by metal particles, the inner surface of the open pores 2A is formed of a metal having excellent heat dissipation. As a result, the heat dissipation can be further improved.
- the paste formed by printing the external electrode 9 includes metal particles and a glass component, and only the metal particles In this case, a layer containing almost no glass component may be disposed on the surface side of the external electrode 9 using two kinds of materials that contain almost no glass component.
- a lead wire is connected to the external electrode 9 as shown in a perspective view showing an example in which the conductive member 8 is bonded to the outside of the external electrode. It is preferable to join the conductive members 8 such as.
- the conductive member 8 is joined to the external electrode 9 by a binder 11 such as solder or a conductive adhesive.
- the conductive member 8 is preferably bonded to the entire area of the external electrode 9 in the stacking direction by the binder 11. In this way, by connecting and fixing the conductive member 8 to the external electrode 9 with the binder 11 such as solder or conductive adhesive, a large current can be passed through the solder, conductive adhesive and conductive member 8.
- the conductive member 8 a lead wire made of a metal wire, a mesh or a mesh-like metal plate, or the like can be used.
- one external electrode 9 is formed on each of two opposing side surfaces of the multilayer body 7 in the above example.
- two external electrodes 9 may be formed on adjacent side surfaces of the multilayer body 7, or It may be formed on the same side of the body 7.
- the cross-sectional shape in the direction orthogonal to the stacking direction of the stacked body 7 is not limited to the quadrangular shape which is an example of the above embodiment, but a polygonal shape such as a hexagonal shape and an octagonal shape, a circular shape, You may be the shape which combined.
- FIG. 1 is a perspective view showing an example of an embodiment of a second multilayer piezoelectric element according to the present invention
- FIG. 2 is a cross-sectional view parallel to the stacking direction of the multilayer piezoelectric element shown in FIG.
- FIG. 10 is an example of an enlarged cross-sectional view of the vicinity of the bonding interface between the multilayer body and the external electrode in the multilayer piezoelectric element shown in FIG.
- the second laminated piezoelectric element 1 is bonded to a laminated body 7 in which piezoelectric layers 3 and internal electrode layers 5 are alternately laminated, and to a side surface of the laminated body 7.
- a multilayer piezoelectric element 1 including an external electrode 9 electrically connected to the internal electrode layer 5, and a plurality of piezoelectric elements 1 inside the external electrode 9 on the surface side, that is, on the opposite side of the multilayer body 7.
- the holes 2B are unevenly present.
- the multilayer piezoelectric element 1 is driven.
- the stress generated in the external electrode 9 when the laminate 7 expands and contracts can be absorbed by the deformation of the plurality of holes 2B.
- a part of the external electrode 9 is peeled off from the side surface of the laminate 7 due to stress, the external electrode 9 is disconnected in the external electrode 9, or between the external electrode 9 and the internal electrode layer 5. It is possible to prevent problems such as disconnection.
- the plurality of holes 2B are not only present in the external electrode 9, but are unevenly distributed on the surface side of the external electrode 9, when the external electrode 9 is continuously driven for a long time, Even when a crack is generated from the joint surface with the laminated body 7, since the progress of the crack can be suppressed by the holes 2B unevenly distributed on the surface side of the external electrode 9, there arises a problem that the external electrode 9 is disconnected. Can be prevented.
- the temperature distribution of the laminate 7 bonded to the external electrode 9 can be reduced. It can be made uniform. That is, the temperature of the multilayer piezoelectric element 1 increases due to self-heating during driving, but an external electrode 9 having a higher thermal conductivity than that of the multilayer body 7 is joined to a part of the side surface of the multilayer body 7. For this reason, the portion joined to the external electrode 9 has improved heat dissipation characteristics, and as a result, a large temperature distribution is generated in the laminate 7 and the thermal stress is increased, and the laminate 7 may be damaged.
- the multilayer piezoelectric element 1 of the present invention since the holes 2B are unevenly distributed on the surface side of the external electrode 9, the thermal conductivity on the surface side of the external electrode 9 can be lowered. It is possible to suppress a large temperature distribution from being generated in the stacked body 7.
- These holes 2B are minute closed pores formed inside the external electrode 9, so-called voids, and are formed inside when the external electrode 9 is formed.
- the shape of the air holes 2B is not particularly limited, and may be, for example, a spherical shape or an elliptical spherical shape, and may be a polyhedral shape or an indefinite shape.
- the size of the hole 2B may be a diameter of 0.5 to 10 ⁇ m when the thickness of the external electrode 9 is 10 to 50 ⁇ m, for example, in the case of a spherical shape. Due to the presence of a plurality of such holes 2B, stress can be effectively absorbed without adversely affecting the resistance and strength of the external electrode 9.
- the plurality of holes 2B are preferably formed on the surface side of the external electrode 9 and in the surface layer portion 9a of the external electrode 9. Accordingly, since the holes 2B are unevenly distributed in the surface layer portion 9a which is the most stressed portion of the external electrode 9, the stress generated in the external electrode 9 can be effectively reduced.
- the surface layer portion 9a of the external electrode 9 is a region up to approximately 2/3 of the thickness of the external electrode 9 on the surface side.
- a glass component is formed on the bonding surface side with the laminated body 7 inside the external electrode 9. It is preferable that 4 is present in a biased manner. As described above, the glass component 4 having a high bonding strength with the piezoelectric layer 3 is unevenly distributed on the bonding surface side with the laminate 7 inside the external electrode 9, whereby the bonding between the external electrode 9 and the internal electrode layer 5 is performed. By increasing the strength, the bonding strength of the external electrode 9 to the side surface of the laminate 7 can be improved.
- the region 9b in which the glass component 4 is biased and present on the joint surface side with the laminate 7 inside the external electrode 9 is approximately 2/3 of the thickness of the external electrode 9 on the laminate 7 side. It is an area.
- the holes 2B on the surface side of the external electrode 9 and making the glass component 4 unevenly distributed on the bonding surface side with the laminated body 7 inside the external electrode 9 a long period of time can be obtained with a high electric field. Even when a load is applied to the multilayer piezoelectric element 1 during continuous driving, microcracks are formed in the glass component 4 having a lower strength than that of the piezoelectric layer 3, and the stress can be dispersed. Further, since the plurality of holes 2B that are unevenly distributed on the surface side of the glass component 4 in the external electrode 9 can prevent the microcrack from being formed in the glass component 4, the external electrode 9 breaks. Thus, the multilayer piezoelectric element 1 having high reliability can be manufactured.
- a plurality of regions 9b in which the glass component 4 of the external electrode 9 is unevenly distributed are also provided. are preferably formed. Thereby, even in the region 9b where the glass component 4 is unevenly distributed, the stress of the external electrode 9 due to the deformation of the holes 2B can be relaxed, and the effect of preventing the external electrode 9 from being peeled off and preventing disconnection can be enhanced. While obtaining the stress dispersion effect due to the microcracks formed in the component 4, it is possible to prevent the microcracks from progressing in the external electrode 9 toward the joint surface with the laminate 7.
- the holes 2B are preferably present in a region between the internal electrode layers 5 adjacent to each other in the laminating direction.
- the stress which arises in the external electrode 9 can be absorbed and relieved by the deformation
- FIG. 13 is an enlarged cross-sectional view showing an example in which the glass layer 10 is formed on the surface layer portion on the joint surface side with the side surface of the laminate 7 of the external electrode 9. That is, by forming the glass layer 10 having high bonding strength with the piezoelectric layer 3 on the surface layer portion 9b on the bonding surface side with the laminated body 7 of the external electrode 9, the side surface of the laminated body 7 of the external electrode 9 is obtained. The bonding strength can be made stronger.
- the thickness of the external electrode 9 is 10 to 50 ⁇ m
- the thickness of the glass layer 10 is preferably in the range of 0.1 to 5 ⁇ m.
- the glass layer 10 made of a glass component on the surface layer portion 9b of the external electrode 9 on the joint surface side with the side surface of the multilayer body 7 a silver glass conductive paste is printed on the side surface of the multilayer body 7. If the external electrode 9 is formed by baking, the external electrode 9 may be baked at a temperature equal to or higher than the softening temperature of the glass component contained in the silver glass conductive paste. Furthermore, in order to form the glass layer 10 reliably, the silver glass conductive paste for forming the external electrode 9 may be formed and baked with a structure of two or more layers.
- a silver glass conductive paste having a high glass component content is used on the bonding surface side with the side surface of the laminate 7, and a silver glass conductive paste having a low glass component content is used on the opposite surface side.
- What is necessary is just to apply
- the glass component in the paste softens and flows when the silver glass conductive paste forming the external electrode 9 is baked, but the piezoelectric layer is added to the silver glass conductive paste on the side of the joint surface with the side surface of the laminate 7. 3 having a high glass wettability content, the glass component can be segregated on the side surface of the laminate 7 in the external electrode 9 during baking.
- the external electrode 9 The glass layer 10 can be reliably formed on the surface layer portion 9b on the side of the joint surface with the side surface of the laminate 7.
- the glass component contained in the silver glass conductive paste to form the glass layer 10 on the external electrode 9 is silica glass, soda lime glass, lead alkali silicate glass, aluminoborosilicate glass having a softening temperature of 600 to 950 ° C. Borosilicate glass, aluminosilicate glass, borate glass, phosphate glass, etc. can be used.
- the thickness of the glass layer 10 is, for example, 0.1 to 5 ⁇ m when the thickness of the external electrode 9 is 10 to 50 ⁇ m, and the thickness of the external electrode 9 is about one-tenth of the thickness, the laminated body 7 of the external electrodes 9. It is preferable for improving the bonding strength with respect to the side surface.
- the glass layer 10 has holes 2B as shown in FIG. 14 in an enlarged sectional view similar to FIG. That is, a glass layer 10 for increasing the bonding strength between the external electrode 9 and the laminated body 7 is formed on the surface layer portion 9 b on the bonding surface side between the external electrode 9 and the laminated body 7.
- 2B the stress generated in the bonding interface between the external electrode 9 and the laminate 7 is formed in the glass layer 10 while keeping the bonding strength between the external electrode 9 and the laminate 7 high. Since 2B can be absorbed and relaxed, it is possible to effectively prevent the problem that the external electrode 9 is peeled off from the side surface of the multilayer body 7 even in continuous driving for a long period of time.
- the holes 2B formed in the glass layer 10 exist in a region between the internal electrode layers 5 adjacent in the laminating direction.
- the glass layer 10 formed on the surface layer portion 9b on the bonding surface side with the laminate 7 which is the portion to which the greatest stress is applied while maintaining good conduction bonding between the external electrode 9 and the internal electrode layer 5 Since the holes 2B are also disposed, the stress dispersion effect in the external electrode 9 is further enhanced.
- one external electrode 9 is formed on each of two opposing side surfaces of the multilayer body 7 in the above example.
- two external electrodes 9 may be formed on adjacent side surfaces of the multilayer body 7, or It may be formed on the same side of the body 7.
- the cross-sectional shape in the direction orthogonal to the stacking direction of the stacked body 7 is not limited to the quadrangular shape which is an example of the above embodiment, but a polygonal shape such as a hexagonal shape or an octagonal shape, a circular shape, or a straight line and an arc. You may be the shape which combined.
- FIG. 15 is a schematic cross-sectional view showing an example of an embodiment of an injection device according to the present invention.
- the injection device 19 of the present example includes a multilayer piezoelectric element of the present invention represented by the example of the above embodiment inside a storage container (container) 23 having an injection hole 21 at one end. 1 is stored.
- a needle valve 25 for opening and closing the injection hole 21 is disposed in the storage container 23 in the storage container 23, a needle valve 25 for opening and closing the injection hole 21 is disposed.
- a fluid passage 27 is disposed in the injection hole 21 so that it can communicate with the movement of the needle valve 25.
- the fluid passage 27 is connected to an external fluid supply source, and fluid is always supplied to the fluid passage 27 at a high pressure. Therefore, when the needle valve 25 opens the injection hole 21, the fluid supplied to the fluid passage 27 is discharged from the injection hole 21 to an external or adjacent container, for example, a fuel chamber (not shown) of the internal combustion engine. It is configured.
- the upper end portion of the needle valve 25 has a large inner diameter, and a cylinder 29 formed in the storage container 23 and a slidable piston 31 are arranged.
- the multilayer piezoelectric element 1 of the present invention described above is stored in the storage container 23.
- the fluid passage 27 may be opened by applying a voltage to the multilayer piezoelectric element 1 and the fluid passage 27 may be closed by stopping the application of the voltage.
- the injection device 19 includes a container 23 having an injection hole 21 and the multilayer piezoelectric element 1 according to the present invention.
- the fluid filled in the container 23 is ejected by driving the multilayer piezoelectric element 1. It may be configured to discharge from the hole 21.
- the multilayer piezoelectric element 1 does not necessarily have to be inside the container 23, as long as the multilayer piezoelectric element 1 is configured to apply pressure for controlling the ejection of fluid to the inside of the container 23 by driving the multilayer piezoelectric element 1. Good.
- the fluid includes various liquid fluids (such as conductive paste) and gas in addition to fuel and ink.
- injection device 19 of the present invention that employs the multilayer piezoelectric element 1 of the present invention is used in an internal combustion engine, fuel can be injected more accurately into a combustion chamber of an internal combustion engine such as an engine over a longer period than in a conventional injection device. Can do.
- FIG. 16 is a schematic diagram showing an example of an embodiment of a fuel injection system according to the present invention.
- the fuel injection system 35 of this example includes a common rail 37 that stores high-pressure fuel as a high-pressure fluid, and a plurality of injection devices 19 of the present invention that inject high-pressure fluid stored in the common rail 37, A pressure pump 39 for supplying high-pressure fluid to the common rail 37 and an injection control unit 41 for supplying a drive signal to the injection device 19 are provided.
- the injection control unit 41 controls the amount and timing of high-pressure fluid injection based on external information or an external signal. For example, if the injection control unit 41 is used for fuel injection of the engine, the amount and timing of fuel injection can be controlled while sensing the situation in the combustion chamber of the engine with a sensor or the like.
- the pressure pump 39 serves to supply fluid fuel from the fuel tank 43 to the common rail 37 at a high pressure.
- the fluid fuel is fed into the common rail 37 at a high pressure of about 1000 to 2000 atmospheres, preferably about 1500 to 1700 atmospheres.
- the high-pressure fuel sent from the pressure pump 39 is stored and sent to the injection device 19 as appropriate.
- the injection device 19 injects a certain fluid from the injection hole 21 to the outside or an adjacent container as described above. For example, when the target for injecting and supplying fuel is an engine, high-pressure fuel is injected in a mist form from the injection hole 21 into the combustion chamber of the engine.
- a ceramic green sheet to be the piezoelectric layer 3 is manufactured. Specifically, a slurry is produced by mixing a calcined powder of piezoelectric ceramic, a binder made of an organic polymer such as acrylic or butyral, and a plasticizer. Then, a ceramic green sheet is produced from this slurry by using a tape molding method such as a doctor blade method or a calender roll method. Piezoelectric ceramics may be used as long as they have piezoelectric characteristics. For example, a perovskite oxide composed of PbZrO 3 —PbTiO 3 can be used. Moreover, as a plasticizer, DBP (dibutyl phthalate), DOP (diethyl phthalate), etc. can be used.
- a plasticizer DBP (dibutyl phthalate), DOP (diethyl phthalate), etc. can be used.
- a conductive paste to be the internal electrode layer 5 is manufactured.
- a conductive paste can be produced by adding and mixing a binder and a plasticizer to silver-palladium metal powder.
- the conductive paste is disposed on the ceramic green sheet in the pattern of the internal electrode layer 5 using a screen printing method. Further, a plurality of ceramic green sheets on which this conductive paste is printed are stacked, debindered at a predetermined temperature, and then fired at a temperature of 900 to 1200 ° C., thereby alternately stacking piezoelectric layers. 3 and the laminated body 7 provided with the internal electrode layer 5 can be formed.
- the laminated body 7 is not limited to the one manufactured by the above manufacturing method, and can be a laminated body 7 in which a plurality of piezoelectric layers 3 and a plurality of internal electrode layers 5 are alternately stacked. It may be formed by any manufacturing method.
- the laminated body 7 obtained by firing is ground to a predetermined shape using a surface grinder or the like.
- a silver glass conductive paste produced by adding a binder, a plasticizer, and a solvent to a conductive material powder and glass powder mainly composed of silver is printed on the side surface of the laminate 7 by screen printing or the like in the pattern of the external electrode 9.
- the external electrode 9 can be formed by drying at a predetermined temperature and baking.
- the surface of the external electrode 9 may be blasted with fine sandblast, dry ice blast or the like. Specifically, by opening the surface of the external electrode 9 with abrasive grains having a particle size of about 3 ⁇ m, the open pores 2A of about 5 ⁇ m can be formed on the surface of the external electrode 9.
- the surface further burns upon baking to a conductive material powder mainly composed of silver.
- a pore forming paste produced by adding a pore material and a binder, a plasticizer, and a solvent that are not printed is printed on the surface of the external electrode 9, dried at a predetermined temperature, and baked, whereby a plurality of open pores 2 ⁇ / b> A are formed on the surface.
- the external electrode 9 provided with can be formed.
- the above-mentioned pore-forming paste is manufactured using a pore material made of acrylic beads having an average particle diameter of 5 ⁇ m, and a silver glass conductive paste is applied and dried on the upper surface. After the paste is applied to a thickness of about 8 ⁇ m and dried, baking is performed at a temperature of 630 to 800 ° C., so that the acrylic beads are not burned during baking, and the external electrode 9 having open pores 2A on the surface is formed. be able to.
- the pore material used for the pore-forming paste is preferably carbon powder or beads made of an organic resin such as acrylic beads. Open pores 2A are formed on the surface of the external electrode 9 after the pore forming paste is baked, according to the shape and size of the pore materials.
- the above-described silver glass conductive paste is printed on the side surface of the laminated body 7 on which the external electrode 9 is formed, dried, and then baked at a predetermined temperature.
- a silver paste produced by adding a binder, a plasticizer and a solvent to a conductive material powder containing silver as a main component on the surface is printed and dried, and then baked at a temperature lower than that of the silver glass conductive paste.
- the external electrode 9 having a plurality of open pores 2A on the surface can be formed. That is, the external electrode 9 having a plurality of open pores 2A on the surface can be formed by baking the silver paste at a temperature at which silver sintering does not proceed.
- the silver glass conductive paste is baked at a temperature of 680 to 950 ° C, and the silver paste printed on the surface is baked at a temperature of 600 to 680 ° C.
- the contained glass component is firmly bonded to the side surface of the laminate 7, while a plurality of open pores 2 ⁇ / b> A can be formed on the surface of the external electrode 9 by sintering the silver powder in the silver paste.
- the open pores 2A In order to form the open pores 2A unevenly distributed on the surface of the external electrode 9 as formed in the region between the internal electrode layers 5 adjacent in the stacking direction, for example, it is not desired to form the open pores 2A.
- the open pores 2A By performing the above-described blasting process in a state where the location is masked, the open pores 2A can be formed at a desired location. Further, for example, the above-mentioned pore forming paste may be applied only to a place where the open pores 2A are to be formed and baked.
- the external electrode 9 having the voids 2B inside the external electrode 9 can be formed.
- the holes 2B can be formed inside the external electrode 9 by increasing the thickness of the silver paste.
- a lead wire made of a metal wire, a conductive member 8 made of a metal mesh or a mesh-like metal plate, etc. are soldered on the surface of the external electrode 9 or a conductive adhesive.
- the bonding material 11 is used for joining and fixing.
- the material of the conductive member 8 is preferably a metal or alloy such as silver, nickel, copper, phosphor bronze, iron, and stainless steel.
- the surface of the conductive member 8 may be plated with silver, nickel, or the like.
- the conductive member 8 may be joined over the entire stacking direction of the external electrodes 9 or may be joined to a part of the external electrodes 9.
- the laminate 7 on which the external electrodes 9 are formed is immersed in a resin solution containing an exterior resin made of silicone rubber. Then, the silicone resin solution is vacuum degassed to bring the silicone resin into close contact with the concavo-convex portions on the outer peripheral side surface of the laminate 7, and then the laminate 7 is pulled up from the silicone resin solution. Thereby, the silicone resin is coated on the side surface of the laminate 7 on which the external electrode 9 is formed.
- each external piezoelectric layer 3 is connected by connecting the external electrode 9 and an external power source via a lead wire as the conductive member 8 and applying a voltage to the piezoelectric layer 3.
- a lead wire as the conductive member 8
- a voltage to the piezoelectric layer 3.
- a silver glass conductive paste manufactured by adding a binder, a plasticizer, and a solvent to a conductive material powder and glass powder containing silver as a main component from a process of manufacturing a ceramic green sheet to be the piezoelectric layer 3 is used for the external electrode 9.
- the process up to the step of printing on the side surface of the laminated body 7 in a pattern by screen printing or the like, then drying at a predetermined temperature and baking is the same as the above-described method for producing the first laminated piezoelectric element according to the present invention. I will omit it.
- the holes 2B In order to form the holes 2B so as to be unevenly distributed on the surface side of the external electrode 9, after printing the silver glass conductive paste that becomes the external electrode 9 after baking on the side surface of the laminate 7 that forms the external electrode 9, By printing and baking a silver conductive paste containing a hole material prepared by dispersing the hole material on the surface, the hole material does not burn during baking, so that a desired surface is formed on the surface side of the external electrode 9. A plurality of holes 2B can be unevenly distributed.
- the pore material carbon powder or beads made of an organic resin such as acrylic beads are preferable.
- a conductive material powder mainly composed of silver and a binder By adding and mixing a conductive material powder mainly composed of silver and a binder to these pore materials. A silver conductive paste containing a pore material can be produced.
- a silver glass conductive paste with a large amount of glass powder added is printed on the side surface of the laminated body 7, and then its surface A silver conductive paste containing a pore material may be printed on and baked.
- a hole material may be added to the silver glass conductive paste printed on the side surface of the laminate 7.
- the silver conductive paste containing the pore material may be printed and baked, or the silver glass conductive paste is printed and baked. Later, a silver conductive paste containing a pore material may be printed and baked.
- the laminate 7 on which the external electrodes 9 are formed is immersed in a resin solution (silicone resin solution) for forming an exterior resin containing silicone rubber.
- a resin solution silicone resin solution
- the silicone resin solution applied to the surface of the laminate 7 on which the external electrode 9 is formed is vacuum degassed so that the silicone resin solution is brought into close contact with the concavo-convex portion on the outer peripheral side surface of the laminate 7, and then the silicone resin solution
- the laminated body 7 is pulled up.
- the exterior resin containing silicone rubber is coated on the side surface of the laminate 7 on which the external electrode 9 is formed.
- a lead wire (not shown) is connected to the external electrode 9 as a current-carrying portion with a conductive adhesive or the like.
- each piezoelectric layer 3 is made to have an inverse piezoelectric effect. It can be displaced greatly. This makes it possible to function as an automobile fuel injection valve that injects and supplies fuel to the engine, for example.
- the stress generated in the external electrode 9 when each piezoelectric layer 3 is greatly displaced and the laminate 7 is greatly expanded and contracted can be relaxed by the plurality of holes 2B, and can be stably for a long period of time.
- the stacked piezoelectric element 1 can be driven.
- a piezoelectric actuator provided with the first multilayer piezoelectric element according to the present invention was manufactured as follows. First, a slurry was prepared by mixing a calcined powder of a piezoelectric ceramic mainly composed of lead zirconate titanate (PbZrO 3 -PbTiO 3 ) having an average particle diameter of 0.4 ⁇ m, a binder, and a plasticizer. Using this slurry, a ceramic green sheet serving as a piezoelectric layer having a thickness of 150 ⁇ m was manufactured by a doctor blade method.
- a slurry was prepared by mixing a calcined powder of a piezoelectric ceramic mainly composed of lead zirconate titanate (PbZrO 3 -PbTiO 3 ) having an average particle diameter of 0.4 ⁇ m, a binder, and a plasticizer.
- a ceramic green sheet serving as a piezoelectric layer having a thickness of 150 ⁇ m was manufactured by a doctor blade method.
- a binder was added to the silver-palladium alloy to produce a conductive paste to be an internal electrode layer.
- a conductive paste serving as an internal electrode layer was printed on one side of the ceramic green sheet by a screen printing method, and 300 ceramic green sheets on which these conductive pastes were printed were laminated. Then, the laminate was obtained by firing at 980 to 1100 ° C.
- the obtained laminate is ground to a predetermined shape using a surface grinder, and then a silver glass conductive paste is applied to the side surface of the laminate forming the external electrode. Thereafter, acrylic powder having an average particle diameter of 5 ⁇ m is applied to the silver powder.
- a pore-forming paste prepared by adding beads and further adding a binder, a plasticizer, and a solvent was printed with a thickness of 8 ⁇ m and baked at 650 ° C.
- a laminated piezoelectric element of sample number 1 having no open pores on the surface of the external electrode outside the scope of the present invention was manufactured. This was obtained by printing a silver glass conductive paste serving as an external electrode, drying, and baking at 950 ° C.
- a plurality of open pores having an average opening diameter of 4 ⁇ m and a depth of 3 ⁇ m are formed on the surface of the external electrode.
- the open pores were approximately 5000 / mm 2 on the surface of the external electrode and were distributed substantially uniformly.
- the average opening diameter was 4 ⁇ m on the surface of the external electrode.
- a plurality of open pores having a depth of 3 ⁇ m, and pores having an average diameter of 4 ⁇ m were formed inside the external electrode.
- the open pores were distributed approximately uniformly at about 5000 / mm 2 on the surface of the external electrode.
- the holes were unevenly distributed near the surface of the external electrode.
- the sample number 2 Open pores similar to those of the multilayer piezoelectric element were formed on the surface of the external electrode, and open pores were also formed at the edge of the external electrode. The open pores were distributed approximately uniformly at about 70 holes / mm 2 .
- the pore paste was printed at a thickness of 8 ⁇ m only in the region between the internal electrode layers adjacent in the laminating direction and baked at 650 ° C.
- the open pores similar to Sample No. 2 were formed in the region between the internal electrode layers adjacent to each other in the stacking direction on the surface of the external electrode.
- the multilayered piezoelectric element of the present invention since a part of the solder for connecting and fixing the conductive member enters the open pores, the bonding strength is improved. It was also found that the conductive member has high reliability without causing the problem of peeling off. In addition, since a plurality of open pores are provided on the surface of the external electrode, the open pores contribute to effectively radiating the heat of the external electrode, so that there is a problem that the external electrode is destroyed by heat generation. There wasn't.
- Sample No. 5 having pores inside the external electrode can absorb the stress generated in the external electrode in combination with the open pores on the surface due to the deformation of the pores. Even cracks did not occur.
- a piezoelectric actuator provided with the second laminated piezoelectric element according to the present invention was manufactured as follows. First, a slurry in which a calcined powder of a piezoelectric ceramic mainly composed of lead zirconate titanate (PbZrO 3 -PbTiO 3 ) having an average particle diameter of 0.4 ⁇ m, a binder, and a plasticizer was prepared. Using this slurry, a ceramic green sheet to be the piezoelectric layer 3 having a thickness of 150 ⁇ m was prepared by the doctor blade method.
- a calcined powder of a piezoelectric ceramic mainly composed of lead zirconate titanate (PbZrO 3 -PbTiO 3 ) having an average particle diameter of 0.4 ⁇ m, a binder, and a plasticizer was prepared. Using this slurry, a ceramic green sheet to be the piezoelectric layer 3 having a thickness of 150 ⁇ m was prepared by the doctor blade method.
- a binder was added to the silver-palladium alloy to produce a conductive paste to be an internal electrode layer.
- a conductive paste serving as an internal electrode layer was printed on one side of the ceramic green sheet by a screen printing method, and 300 ceramic green sheets on which these conductive pastes were printed were laminated. Then, the laminate was obtained by firing at 980 to 1100 ° C. Next, the obtained laminate was ground into a predetermined shape using a surface grinder.
- a silver paste containing pores prepared by adding a binder and a plasticizer to spherical acrylic beads (average particle size 5 ⁇ m) as pores and silver powder, pores, silver powder and glass powder Add the binder and plasticizer to the silver-filled conductive glass paste with pores prepared by adding binder and plasticizer (softening temperature 730 °C), and silver powder and glass powder (softening temperature 730 °C)
- a silver glass conductive paste was prepared.
- any one or a plurality of pastes described above was printed on the side surface of the laminate, which is the formation surface of the external electrode, and baked at 700 ° C. to produce a multilayer piezoelectric element.
- sample number 12 printed with a silver glass conductive paste on the side surface of the laminate and printed with a silver paste containing a pore material on the surface thereof was baked. An average diameter of 3 ⁇ m) was formed, and the glass component was unevenly distributed on the joint surface side with the laminate.
- a silver glass conductive paste, a silver glass conductive paste with a pore material, and a silver paste with a pore material were printed in this order and baked on sample number 13 from the surface side of the external electrode.
- a region where holes are formed, a region where holes and glass components are mixed, and a region where glass components are unevenly distributed are formed toward the joint surface with the laminate.
- Sample number 14 produced by the same manufacturing method as sample number 11 except that the softening temperature of the glass contained in the silver glass conductive paste was 600 ° C. and baking was performed at 700 ° C. A glass layer having an average thickness of 1 ⁇ m was formed at the bonding interface, and voids were formed on the surface side of the external electrode.
- the piezoelectric actuator of Sample No. 11, which is a comparative example of the present invention is not driven because a plurality of holes that are unevenly distributed on the surface side are not formed inside the external electrode.
- the stress generated in the external electrode due to expansion and contraction of the laminate cannot be absorbed, and after driving 1 ⁇ 10 9 times, a part of the external electrode peels off from the side surface of the laminate, and the displacement characteristic is halved. It had fallen.
- the piezoelectric actuators of sample numbers 12 to 14 which are the embodiments of the present invention, a plurality of holes are unevenly distributed on the surface side inside the external electrode, so that the holes are deformed due to stress generated during driving. In particular, even after driving 1 ⁇ 10 9 times, there was no problem that a part of the external electrode peeled off from the side surface of the laminated body and the displacement characteristics deteriorated.
- sample number 14 with a glass layer formed on the part even after driving 1 ⁇ 10 10 times, a part of the external electrode does not peel from the side surface of the laminate and the displacement characteristics do not deteriorate, and the durability is high It turns out that it is equipped.
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- Fuel-Injection Apparatus (AREA)
Abstract
Description
図1は、本発明に係る第1の積層型圧電素子の実施の形態の一例を示す斜視図であり、図2は、図1に示す積層型圧電素子の積層方向に平行な断面図である。図3は、図2に示す積層型圧電素子における積層体と外部電極との接合界面近傍の拡大断面図の一例である。
図1は、本発明に係る第2の積層型圧電素子の実施の形態の一例を示す斜視図であり、図2は、図1に示す積層型圧電素子の積層方向に平行な断面図である。また、図10は、図2に示す積層型圧電素子における積層体と外部電極との接合界面近傍の拡大断面図の一例である。
次に、本発明に係る噴射装置の実施の形態の一例について説明する。図15は、本発明に係る噴射装置の実施の形態の一例を示す概略断面図である。
次に、本発明に係る燃料噴射システムの実施の形態の一例について説明する。図16は、本発明に係る燃料噴射システムの実施の形態の一例を示す概略図である。
本発明に係る第1の積層型圧電素子の製造方法について説明する。
本発明に係る第1の積層型圧電素子を備えた圧電アクチュエータを以下のようにして製作した。まず、平均粒径が0.4μmのチタン酸ジルコン酸鉛(PbZrO3-PbTiO3)を主成分とする圧電セラミックスの仮焼粉末、バインダーおよび可塑剤を混合したスラリーを製作した。このスラリーを用いてドクターブレード法により厚みが150μmの圧電体層となるセラミックグリーンシートを製作した。
本発明に係る第2の積層型圧電素子を備えた圧電アクチュエータを以下のようにして作製した。まず、平均粒径が0.4μmのチタン酸ジルコン酸鉛(PbZrO3-PbTiO3)を主成分とする圧電セラミックスの仮焼粉末、バインダーおよび可塑剤を混合したスラリーを作製した。このスラリーを用いてドクターブレード法により厚みが150μmの圧電体層3となるセラミックグリーンシートを作製した。
一方、本発明の実施例である試料番号12~14の圧電アクチュエータでは、外部電極の内部において表面側に複数の空孔を偏在させてあることから、駆動時に生じる応力をこの空孔が変形することに吸収することができるため、1×109回の駆動後にも外部電極の一部が積層体の側面から剥離して変位特性が低下するといった問題は生じていなかった。
2A・・・開気孔
2B・・・空孔
3・・・・圧電体層
5・・・・内部電極層
7・・・・積層体
8・・・・導電部材
9・・・・外部電極
10・・・・ガラス層
11・・・・結合材
19・・・・噴射装置
21・・・・噴射孔
23・・・・収納容器(容器)
25・・・・ニードルバルブ
27・・・・流体通路
29・・・・シリンダ
31・・・・ピストン
33・・・・皿バネ
35・・・・燃料噴射システム
37・・・・コモンレール
39・・・・圧力ポンプ
41・・・・噴射制御ユニット
43・・・・燃料タンク
Claims (17)
- 圧電体層および内部電極層が交互に積層された積層体と、該積層体の側面に接合されて前記内部電極層に電気的に接続された外部電極とを含む積層型圧電素子であって、前記外部電極の表面には、複数の開気孔が形成されていることを特徴とする積層型圧電素子。
- 前記開気孔が前記外部電極の縁部にも形成されていることを特徴とする請求項1に記載の積層型圧電素子。
- 前記開気孔が積層方向に隣接した前記内部電極層間の領域において形成されていることを特徴とする請求項1または請求項2に記載の積層型圧電素子。
- 前記開気孔が積層方向に隣接した前記内部電極層間の領域において複数形成されていることを特徴とする請求項3に記載の積層型圧電素子。
- 前記外部電極の内部に空孔が形成されていることを特徴とする請求項1乃至請求項4のいずれかに記載の積層型圧電素子。
- 前記開気孔が前記外部電極を構成する金属粒子間に形成されていることを特徴とする請求項1乃至請求項5のいずれかに記載の積層型圧電素子。
- 前記外部電極に導電部材を接合したことを特徴とする請求項1乃至請求項6のいずれかに記載の積層型圧電素子。
- 圧電体層および内部電極層が交互に積層された積層体と、該積層体の側面に接合されて前記内部電極層に電気的に接続された外部電極とを含む積層型圧電素子であって、前記外部電極の内部に複数の空孔が表面側に偏って存在していることを特徴とする積層型圧電素子。
- 前記空孔が前記外部電極の表層部に存在していることを特徴とする請求項8に記載の積層型圧電素子。
- 前記外部電極の内部にガラス成分が前記積層体との接合面側に偏って存在していることを特徴とする請求項8または請求項9に記載の積層型圧電素子。
- 前記外部電極の前記ガラス成分が偏在している領域にも複数の前記空孔が形成されていることを特徴とする請求項10に記載の積層型圧電素子。
- 前記空孔が積層方向に隣接した前記内部電極層間の領域に存在していることを特徴とする請求項8乃至請求項11のいずれかに記載の積層型圧電素子。
- 前記外部電極の前記積層体との接合面側の表層部に、前記ガラス成分からなるガラス層が形成されていることを特徴とする請求項8乃至請求項12のいずれかに記載の積層型圧電素子。
- 前記ガラス層にも前記空孔が形成されていることを特徴とする請求項13に記載の積層型圧電素子。
- 前記空孔が積層方向に隣接した前記内部電極層間の領域に存在していることを特徴とする請求項14に記載の積層型圧電素子。
- 噴出孔を有する容器と、請求項1乃至請求項15のいずれかに記載の積層型圧電素子とを備え、前記容器内に蓄えられた液体が前記積層型圧電素子の駆動により前記噴射孔から吐出されることを特徴とする噴射装置。
- 高圧燃料を蓄えるコモンレールと、該コモンレールに蓄えられた前記高圧燃料を噴射する請求項16に記載の噴射装置と、前記コモンレールに前記高圧燃料を供給する圧力ポンプと、前記噴射装置に駆動信号を与える噴射制御ユニットとを備えたことを特徴とする燃料噴射システム。
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US13/061,088 US20110168806A1 (en) | 2008-08-26 | 2009-08-21 | Multi-Layer Piezoelectric Element, and Injection Device and Fuel Injection System Using the Same |
EP09809850.2A EP2337103A4 (en) | 2008-08-26 | 2009-08-21 | MULTILAYER PIEZOELECTRIC ELEMENT, INJECTOR THEREOF AND FUEL INJECTION SYSTEM |
CN2009801334882A CN102132432A (zh) | 2008-08-26 | 2009-08-21 | 层叠型压电元件及使用该层叠型压电元件的喷射装置以及燃料喷射*** |
JP2010526683A JPWO2010024199A1 (ja) | 2008-08-26 | 2009-08-21 | 積層型圧電素子およびこれを用いた噴射装置ならびに燃料噴射システム |
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Cited By (3)
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JP2012174981A (ja) * | 2011-02-23 | 2012-09-10 | Kyocera Corp | 積層型圧電素子およびこれを備えた噴射装置ならびに燃料噴射システム |
JP5465337B2 (ja) * | 2010-10-28 | 2014-04-09 | 京セラ株式会社 | 積層型圧電素子およびそれを用いた噴射装置ならびに燃料噴射システム |
JP2015531548A (ja) * | 2012-09-28 | 2015-11-02 | エプコス アクチエンゲゼルシャフトEpcos Ag | 電子デバイスおよび電子デバイスの接続部の生成方法 |
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JP5329544B2 (ja) * | 2008-07-29 | 2013-10-30 | 京セラ株式会社 | 燃料噴射システム |
JP6011006B2 (ja) * | 2012-04-27 | 2016-10-19 | ブラザー工業株式会社 | 液滴噴射装置 |
DE102012104830A1 (de) * | 2012-06-04 | 2013-12-05 | Epcos Ag | Vielschichtbauelement und Verfahren zum Herstellen eines Vielschichtbauelements |
WO2019225759A1 (ja) * | 2018-05-24 | 2019-11-28 | 京セラ株式会社 | 光学装置 |
JP7074201B2 (ja) * | 2018-09-27 | 2022-05-24 | 株式会社村田製作所 | モジュールおよびその製造方法 |
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US20110168806A1 (en) | 2011-07-14 |
CN102132432A (zh) | 2011-07-20 |
JPWO2010024199A1 (ja) | 2012-01-26 |
EP2337103A1 (en) | 2011-06-22 |
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