CN1314007A - Piezo-multilayer actuator with improved electrode contact - Google Patents
Piezo-multilayer actuator with improved electrode contact Download PDFInfo
- Publication number
- CN1314007A CN1314007A CN00801103A CN00801103A CN1314007A CN 1314007 A CN1314007 A CN 1314007A CN 00801103 A CN00801103 A CN 00801103A CN 00801103 A CN00801103 A CN 00801103A CN 1314007 A CN1314007 A CN 1314007A
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- external electrode
- electrode
- reinforcement
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- join domain
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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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
- B81B3/00—Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes
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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
- H10N30/871—Single-layered electrodes of multilayer piezoelectric or electrostrictive devices, e.g. internal electrodes
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- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Fuel-Injection Apparatus (AREA)
- General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
Abstract
A piezo-multilayer actuator having a plurality of piezoceramic layers arranged in a stack and a plurality of inner electrodes interleaved in the piezoceramic layers, the plurality of inner electrodes extending from first and second sides of the stack in alternating fashion. First and second outer electrodes are connected to the plurality of inner electrodes extending respectively from the first and second sides of the stack. The inner electrodes include thickened portions at the first and second connection areas, the thickened portions being thicker than other portions of the plurality of inner electrodes so as to reinforce the inner electrodes. Cracks which may form on the inner electrodes due to tensile stresses tend to migrate around the thicker portions of the inner electrodes at the first and second connection areas. Propagation of the cracks to the outer electrodes with the attendant possibility of current interruption in the outer electrodes, is thereby reduced or halted.
Description
The present invention generally relates to the piezoelectric type multi-layered devices, relates in particular to the piezoelectric type multi-layer actuator of the band anti cracking device that is used for the diesel injection device.
Use the brake of multilayer piezoelectric ceramic device to can be used in the diesel fuel injection apparatus of explosive motor.Piezoelectric ceramic has such characteristic, and promptly under mechanical pressure or tensile force effect, they produce electric charge, when charge generation, and their expansions or contraction.In order to strengthen this effect, used the multilayer brake of monolithic, bury the lead zirconate titanate of metal inner electrode in it is piled, for example had by the sintering of piezoceramics film and form.Interior electrode stretches out heap in an alternating manner and connects by external electrode side by side.On the contact side of heap, applied the first metal layer or external electrode, they are connected to electrode in each.
If external electrode has been applied a voltage, then piezoelectric membrane is expanded on direction of an electric field.By each piezoelectric membrane of mechanical connection in series, even on low-voltage, also can obtain the specified expansion of whole piezoelectric ceramic.
The brake of these monolithic multilayers is described in detail among the Deutsche Bundespatent No.4036287C2.The application of these brakes in the stream adjuster valve also described therein.
The interior electrode of this piezoceramic multilayer brake can be by the thick Ag collodion silk reticulated printing of about 4 μ m, or under rare situation by the thick CuNi layer sputter of about 1 μ m.The result that electrode that use as electric insulation, interior alternately is offset backward to external electrode forms the electric field that weakens on the outward flange of piezoelectric membrane heap, thus in these zones the expansion of this piezoelectric membrane less than expansion in the central area of heap.Consequently, tensile stress in exterior lateral area, occurs and reach after surpassing its adhesive strength, in piezoelectric thin film layer reaches, produced layer separation between the electrode and on electrode, formed crackle.This crackle can outwards move in the external electrode, and will cause the blocking-up of electric current after crackle runs through.
German patent application No.19648545A1 has described a kind of monolithic multi-layer actuator of improvement, with in addition also can avoid the damage of this multi-layer actuator when the big line load.This application is described the conduction side electrode of a three-dimensional structure, and it is connected on the discrete contact point of external electrode and is configured as between contact point expands by welding.The wavy side electrode of a trough of belt on its contact point for example, has been described.The operating current of actuator is divided into secondary current by this structure.This secondary current flows to metal inner electrode from contact point by external electrode.The crackle that causes in external electrode only causes secondary current to change its course by three-diemsnional electrode, and electric current is not blocked.But this side electrode is an optional feature that must be welded in place, and this has brought fringe cost.And between solder joint and side electrode, cut the separation that seam can cause the side electrode.
The invention provides a kind of piezoelectric type multi-layer actuator, comprising: a plurality of piezoelectric material layers, they are arranged in the heap with first and second side; Electrodes in a plurality of, they are arranged between a plurality of piezoelectric material layers, and electrodes were extended by first and second side respectively in the mode that replaces in these were a plurality of, to form in first group electrode in electrode and second group.The first external electrode is arranged in the first heap side, and this first external electrode is connected with electrode in first group on first join domain; Reach the second external electrode and be arranged in the second heap side, this second external electrode is connected with electrode in second group on second join domain.Electrode was included in the reinforcement on first and second join domain in these were a plurality of, and this reinforcement is thicker than the other part of electrode in a plurality of.
The present invention also provides a kind of method of making the piezoelectric type multi-layer actuator, and this method comprises: a plurality of piezoelectric material layers are set, and they are arranged in the heap with first and second side; And be provided with a plurality of in electrodes, they are arranged between a plurality of piezoelectric material layers, electrodes were extended by first and second side respectively in the mode that replaces in these were a plurality of, to form in first group electrode in electrode and second group respectively.This method also comprises: the first external electrode that is arranged in the first heap side is set, and this first external electrode is connected with electrode in first group on first join domain; Setting is arranged in the second external electrode of the second heap side, and this second external electrode is connected with electrode in second group on second join domain; And will be on first and second join domain this a plurality of in the electrode thickening to form reinforcement, this reinforcement is thicker than the other part of electrodes in a plurality of.
Fig. 1 represents to be decorated with the summary cross-sectional view of piezoceramic multilayer actuator of the prior art of electric field line.
Fig. 2 represent to describe electrode separation and Fig. 1 of breaking in the details of piezoceramic multilayer actuator of prior art.
Fig. 3 represents the summary cross-sectional view according to a part in the piezoceramic multilayer actuator of the present invention.
Fig. 4 represents to describe the details of actuator among Fig. 3 that crackle changes direction.
Fig. 5 represents the summary cross-sectional view according to a part in the piezoceramic multilayer actuator with wavy external electrode of the present invention.
Fig. 6 represents the summary cross-sectional view according to a part in the piezoceramic multilayer actuator with external electrode of the present invention, and this external electrode has long narrow contact area and separate the zone of extension with heap between the contact area.
Fig. 1 represents to have the piezoelectric type multi-layer actuator 10 of a prior art of the electric field line of using letter " E " indication.This actuator 10 comprises the heap 12 of piezoceramics film 2.Electrode 22 and 32 is inserted in and also stretches out heap 12 in the film 2 respectively in an alternating manner on opposite side 14 and 16 in first and second group.Each first interior electrode 22 is connected with the first external electrode 42 on each tie point 24, and each the second inner electrode 32 is connected with the first external electrode 52 on each tie point 4.The first interior electrode 22 departs from the second external electrode 52 and the second inner electrode 32 departs from the first external electrode 42, as shown in the figure, and so that the electric insulation between the first interior electrode 22 and the second external electrode 52 and the second inner electrode 32 and the first external electrode 42 to be provided respectively.In departed from the zone 62 that forms by these, the electric field that is formed by the first interior electrode 22 and the second inner electrode 32 is distorted, shown in letter " E ".Therefore electric field is weakened in zone 62.
Referring now to Fig. 2, the expansion of piezoelectric membrane is less than the other zone of heap 12 in zone 62, and this has caused stress.This has just produced the burble point 70 and the crack 72 of layer.Crack 72 can outwards be moved and form breaking joint at last in the first external electrode 42 or the second external electrode 52, has blocked electric current flowing in external electrode.
Fig. 3 represents according to piezoelectric type multi-layer actuator 10 of the present invention.In the heap 12 of piezoceramics film 2 in first the layout of the insertion of electrode 22 and the second inner electrode 32 and skew and the first external electrode 42 and the second external electrode 52 be connected the actuator that is substantially similar to above-mentioned prior art.But in the enforcement here, the first interior electrode 22 and the second inner electrode 32 are respectively equipped with reinforcement 26 in the zone of tie point 24 and 34, and electrode is connected with first and second external electrode 42 and 52 respectively in these offices, thickening part.Reinforcement 26 is thicker than other zone of interior electrode, has therefore strengthened electrode in these at tie point 24 and 34 places.
Referring now to Fig. 4, the execution mode owing to according to reinforcement 26 of the present invention also can produce burble point 70 and crack 72, but the crack is tending towards in moving around the thickening point 26 and being limited in than the zonule.The change of this direction of breaking has consumed energy of rupture, and the propagation clear length of breaking is shortened.Effective extension length that reinforcement 26 makes propagation direction in external electrode 42 and 52 " y " go up crack 72 increases (Fig. 4).The stress that causes by breaking in external electrode reduces thus.(Fig. 4) can select to such an extent that make stress in the external electrode be lower than the tensile strength of electrode to the thickness " t " of reinforcement, in case the crack arrest seam penetrates external electrode fully.
By selecting external electrode 42 and 52 in the tensile strength and the adhesion strength at reinforcement 26 places and make tensile strength, can obtain more favourable effect greater than adhesion strength.This will be tending towards making the crack to follow the profile of reinforcement, and can not penetrate whole external electrode.
Therefore, reinforcement 26 has reduced the trend of crack propagation and can prevent that it from breaking fully.
It is spherical that reinforcement 26 preferably is generally, but can be various arbitrary shapes in other embodiments.Suitable in addition shape comprises hemispherical or mushroom and ellipticity.The profile that is generally arc and does not have a big turning is suitable.
With reference to Fig. 5, first and second external electrode 42 and 52 can be respectively wavy, as the lateral electrode described at above-mentioned German patent application No.1964854A1.According to the present invention, first and second wavy external electrode 42 and 52 can connect by hard solder or soft soldering respectively, for example is directly connected to respectively on the reinforcement 26 of first and second interior electrode 22 and 32.
Wavy external electrode can be avoided breaking fully in external electrode.The crack is tending towards moving along friendship place that connects between the metal of piezoceramics film 2 and interior electrode 22 or 32.When crack 72 reaches ceramic reinforcement-air and connects friendship place 80 1 sides 14, as shown in Figure 5, the crack will be tending towards moving around reinforcement, but not move into the thickness part.In addition, wavy external electrode is flexible on the propagation direction " y " of piezoceramics film 2, and stretching and shear stress on the tie point that causes with regard to the expansion that makes by piezoelectric actuator reduce widely.
Referring now to Fig. 6, in another embodiment according to actuator of the present invention, first and second external electrode 42 and 52 is respectively equipped with straight line portion and sweep 46 alternately, and they extend dividually with heap 12.In this embodiment of the present invention, straight line portion 44 is directly connected to the reinforcement of first and second interior electrode 22 and 32 respectively.The advantage of above-mentioned corrugated electrode still is retained.In addition, straight line portion 44 can make first and second external electrode 42 and 52 by providing long narrow connection surface 45 to be easy to be connected with reinforcement 26 respectively, and its reliable connection does not rely on the interval between the electrode 22 and 32 in first and second basically.
Claims (24)
1. piezoelectric type multi-layer actuator comprises:
A plurality of piezoelectric material layers, they are arranged in the heap with first and second side;
Electrodes in a plurality of, they are arranged between a plurality of piezoelectric material layers, and electrodes were extended by first and second side respectively in the mode that replaces in these were a plurality of, to form in first group electrode in electrode and second group;
Be arranged in the first external electrode of the first heap side, this first external electrode is connected with electrode in first group on first join domain; And
Be arranged in the second external electrode of the second heap side, this second external electrode is connected with electrode in second group on second join domain;
Wherein these a plurality of interior electrodes are included in the reinforcement on first and second join domain, and this reinforcement is thicker than the other part of electrodes in a plurality of.
2. according to the piezoelectric type multi-layer actuator of claim 1, wherein a plurality of piezoelectric material layers comprise piezoceramics layer.
3. according to the piezoelectric type multi-layer actuator of claim 1, wherein reinforcement uses and electroplates, photomask, and at least a method in chemical deposition and the silk screen printing forms.
4. according to the piezoelectric type multi-layer actuator of claim 1, wherein reinforcement comprises copper, nickel, silver, at least a material in gold and the alloy.
5. according to the piezoelectric type multi-layer actuator of claim 4, wherein this alloy comprises silver-palladium alloy, at least a material in brass and the bronze.
6. according to the piezoelectric type multi-layer actuator of claim 1, wherein reinforcement is formed by the multilayer of at least a material of at least a metal and at least a alloy.
7. according to the piezoelectric type multi-layer actuator of claim 1, wherein reinforcement can reduce the propagation of stress cracking.
8. according to the piezoelectric type multi-layer actuator of claim 1, wherein the shape that has of reinforcement comprises sphere, hemisphere, a kind of shape in mushroom-shaped and the ellipse at least.
9. according to the piezoelectric type multi-layer actuator of claim 1, wherein at least a external electrode and the heap between each first and second join domain extend dividually in first and second external electrode.
10. according to the piezoelectric type multi-layer actuator of claim 9, wherein at least a external electrode is included in straight line portion on each first and second join domain substantially in first and second external electrode.
11. according to the piezoelectric type multi-layer actuator of claim 9, wherein at least a external electrode is wavy in first and second external electrode.
12. according to the piezoelectric type multi-layer actuator of claim 1, wherein this actuator is included in the diesel injection device.
13. a method of making the piezoelectric type multi-layer actuator, this method comprises:
A plurality of piezoelectric material layers are set, and they are arranged in the heap with first and second side;
Be provided with a plurality of in electrodes, they are arranged between a plurality of piezoelectric material layers, electrodes were extended by first and second side respectively in the mode that replaces in these were a plurality of, to form in first group electrode in electrode and second group respectively;
Setting is arranged in the first external electrode of the first heap side, and this first external electrode is connected with electrode in first group on first join domain;
Setting is arranged in the second external electrode of the second heap side, and this second external electrode is connected with electrode in second group on second join domain; And
The electrode thickening was to form reinforcement in this that will be on first and second join domain was a plurality of, and this reinforcement is thicker than the other part of electrodes in a plurality of.
14. according to the method for claim 13, wherein a plurality of piezoelectric material layers comprise piezoceramics layer.
15. according to the method for claim 13, wherein reinforcement uses and electroplates, photomask, and at least a method in chemical deposition and the silk screen printing forms.
16. according to the method for claim 13, wherein reinforcement comprises copper, nickel, silver, at least a material in gold and the alloy.
17. according to the method for claim 16, wherein this alloy comprises silver-palladium alloy, at least a material in brass and the bronze.
18. according to the method for claim 13, wherein reinforcement is formed by the multilayer of at least a material at least a metal and at least a alloy.
19. according to the method for claim 13, wherein the thickening of interior electrode realizes on first and second join domain, so that has reduced the propagation of stress cracking.
20. according to the method for claim 13, wherein the shape that has of reinforcement comprises sphere, hemisphere, a kind of shape in mushroom-shaped and the ellipse at least.
21. according to the method for claim 13, wherein at least a external electrode and the heap between each first and second join domain extend dividually in first and second external electrode.
22. according to the method for claim 21, wherein at least a external electrode is included in straight line portion on each first and second join domain substantially in first and second external electrode.
23. according to the method for claim 21, wherein at least a external electrode is wavy in first and second external electrode.
24. according to the method for claim 13, wherein this actuator is included in the diesel injection device.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US33931299A | 1999-06-23 | 1999-06-23 | |
| US09/339,312 | 1999-06-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1314007A true CN1314007A (en) | 2001-09-19 |
Family
ID=23328439
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN00801103A Pending CN1314007A (en) | 1999-06-23 | 2000-06-17 | Piezo-multilayer actuator with improved electrode contact |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP1110252A1 (en) |
| JP (1) | JP2003503859A (en) |
| KR (1) | KR20010072858A (en) |
| CN (1) | CN1314007A (en) |
| CZ (1) | CZ2001665A3 (en) |
| WO (1) | WO2001001499A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1774822B (en) * | 2004-06-29 | 2010-05-05 | 西门子公司 | Piezoelectric component with a predetermined breaking point, method for producing the component and use of the component |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1225645A3 (en) * | 2001-01-17 | 2005-09-21 | Piezomechanik GmbH | Solid state actuator and its manufacturing method |
| US6700306B2 (en) * | 2001-02-27 | 2004-03-02 | Kyocera Corporation | Laminated piezo-electric device |
| EP1289027A1 (en) * | 2001-08-30 | 2003-03-05 | Océ-Technologies B.V. | Multilayer piezoelectric actuator |
| DE102004031404B4 (en) * | 2004-06-29 | 2010-04-08 | Siemens Ag | Piezoelectric component with predetermined breaking point and electrical connection element, method for producing the component and use of the component |
| DK1944813T3 (en) * | 2005-09-16 | 2011-06-06 | Delphi Tech Holding Sarl | Piezoelectric actuator |
| JP2007149995A (en) | 2005-11-28 | 2007-06-14 | Fujifilm Corp | Multilayer piezoelectric element and method for manufacturing the same |
| JP4936306B2 (en) | 2006-01-13 | 2012-05-23 | 日本碍子株式会社 | Multilayer piezoelectric element and manufacturing method thereof |
| JP4498299B2 (en) * | 2006-03-27 | 2010-07-07 | 京セラ株式会社 | Manufacturing method of multilayer piezoelectric element |
| JP5105790B2 (en) * | 2006-07-27 | 2012-12-26 | 京セラ株式会社 | Manufacturing method of multilayer piezoelectric element |
| JP5656352B2 (en) * | 2008-10-14 | 2015-01-21 | 太陽誘電株式会社 | Multilayer piezoelectric actuator |
| DE102011014296A1 (en) * | 2011-03-17 | 2012-09-20 | Epcos Ag | Piezoelectric actuator component and method for producing a piezoelectric Aktorbauelements |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61234580A (en) * | 1985-04-11 | 1986-10-18 | Jgc Corp | Laminated type electrostriction of piezoelectric element |
| JPH0529680A (en) * | 1991-07-25 | 1993-02-05 | Hitachi Metals Ltd | Laminated displacement element and manufacture thereof |
| JPH06232474A (en) * | 1993-02-08 | 1994-08-19 | Brother Ind Ltd | Manufacture of laminated piezo-electric element |
| JPH08148731A (en) * | 1994-11-21 | 1996-06-07 | Sumitomo Metal Ind Ltd | Multilayer piezoelectric actuator |
| DE19648545B4 (en) * | 1996-11-25 | 2009-05-07 | Ceramtec Ag | Monolithic multilayer actuator with external electrodes |
-
2000
- 2000-06-17 JP JP2001506625A patent/JP2003503859A/en active Pending
- 2000-06-17 WO PCT/EP2000/005585 patent/WO2001001499A1/en not_active Application Discontinuation
- 2000-06-17 CN CN00801103A patent/CN1314007A/en active Pending
- 2000-06-17 EP EP00942091A patent/EP1110252A1/en not_active Withdrawn
- 2000-06-17 KR KR1020017002257A patent/KR20010072858A/en not_active Withdrawn
- 2000-06-17 CZ CZ2001665A patent/CZ2001665A3/en unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1774822B (en) * | 2004-06-29 | 2010-05-05 | 西门子公司 | Piezoelectric component with a predetermined breaking point, method for producing the component and use of the component |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2001001499A1 (en) | 2001-01-04 |
| CZ2001665A3 (en) | 2002-01-16 |
| EP1110252A1 (en) | 2001-06-27 |
| KR20010072858A (en) | 2001-07-31 |
| JP2003503859A (en) | 2003-01-28 |
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