Abstract: A multi-layer piezoelectric element having high durability of which amount of displacement is suppressed from varying even when operated continuously over a long period of time with a higher electric field under a high pressure is provided. The multi-layer piezoelectric element comprising a multi-layer structure in which a plurality of piezoelectric material layers and a plurality of metal layers are stacked alternately one on another, wherein the plurality of metal layers comprises internal electrodes and low-rigidity metal layer that has rigidity lower than those of the piezoelectric material layer and the internal electrode, wherein the low-rigidity metal layer comprises a plurality of metal parts that are separated from each other, and wherein at least one of the metal parts is bonded with only one piezoelectric material layer among the two piezoelectric material layers that adjoin in the stacking direction.

Abstract: In a multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are stacked alternately, the plurality of metal layers include a plurality of low-filled metal layers having a lower filling rate of metal composing the metal layers than oppositely disposed metal layers adjacent to each other in a stacking direction. In a multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are stacked alternately, the plurality of metal layers include a plurality of thin metal layers having a smaller thickness than oppositely disposed metal layers adjacent to each other in a stacking direction.

Abstract: A multi-layer piezoelectric element having high durability of which amount of displacement is suppressed from varying even when operated continuously over a long period of time with a higher electric field under a high pressure is provided. The multi-layer piezoelectric element which has a multi-layer structure, the multi-layer structure comprising a plurality of piezoelectric material layers and a plurality of metal layers that are stacked alternately, wherein the piezoelectric material layer is constituted from a plurality of piezoelectric crystal grains, the plurality of metal layers comprise internal electrodes and low-rigidity metal layer that has rigidity lower than those of the internal electrodes and the piezoelectric material layer, and wherein the low-rigidity metal layer has a plurality of metal parts that are separated from each other, and an end of the metal part infiltrates between the piezoelectric crystal grains.

Abstract: This aims to provide a multi-layer piezoelectric element, which is made excellent in durability and suppressed in the reduction of a displacement degree, even if the element is largely displaced or driven at a high speed, and an injection device and a fuel injection system using the element. The multi-layer piezoelectric element comprises a stacked body comprising a plurality of ceramic layers and a plurality of internal electrode layers, each of the plurality of internal electrode layers being sandwiched between ceramic layers of the plurality of ceramic layers that are located opposite to each other. The plurality of ceramic layers comprises a plurality of piezoelectric layers, and a low-rigidity ceramic layer which has a rigidity lower than that of the plurality of piezoelectric layers and that of the plurality of internal electrode layers.

Abstract: Provided is a multi-layer piezoelectric element in which the amount of the positional displacement can be suppressed even when continuous driving is performed for a long time under high electrical field and high pressure, and which may have a good durability. The laminated piezoelectric element comprises a stacked body in which piezoelectric layers and metal layers are stacked alternately one on another. The metal layers comprise internal electrodes and a low-rigidity metal layer which has rigidity lower than those of the piezoelectric layer and the internal electrode. The low-rigidity metal layer comprises a plurality of metal parts isolated from each other via voids, and a covering layer which covers at least a part of the metal parts.

Abstract: Provided is a highly durable laminated piezoelectric element wherein a stress generated at a portion, i.e., the boundary between an active region and inactive region, is reduced. A method for manufacturing such laminated piezoelectric element is also provided. The laminated piezoelectric element has a laminated structure (15) wherein a plurality of piezoelectric layers (11) and internal electrode layers (13) are alternately laminated. The piezoelectric layer (11) contains a metal element other than those elements constituting piezoelectric ceramic, i.e., the main component of the piezoelectric layer (11), and at a portion (11a) of the piezoelectric layer (11) at the vicinity of an end of the internal electrode layer (13), metal particles having a metal element as a main component exist. The content of the metal at the portion (11a) at the vicinity of the end is higher than the content of a compound of the metal element and a nonmetal element.

Abstract: A laminated piezoelectric element having a laminated structure in which a plurality of piezoelectric layers and a plurality of internal electrodes are alternately laminated is provided. This laminated structure has an opposing section wherein an internal electrode on an anode side and an internal electrode on a cathode side which are adjacent to each other in the laminating direction, oppose in the laminating direction, and an end-side non-opposing section situated in a position closer to end in the laminating direction than the opposing section. This end-side non-opposing section has a porous section having porosity larger than that of the internal electrodes.

Abstract: A multi-layer piezoelectric element having high durability which allows it to increase the amount of displacement of a piezoelectric actuator under high voltage and high pressure and does not undergo a change in the amount of displacement during continuous operation in a high electric field and under a high pressure over a long time period is provided. The multi-layer piezoelectric element comprises a stack of at least one piezoelectric layer and a plurality of internal electrodes consisting of first and second internal electrodes placed one on another, a first external electrode formed on a first side face of the stack and connected to the first internal electrode and a second external electrode formed on a second side face of the stack and connected to the second internal electrode, wherein the bonding strength between the piezoelectric layer and the internal electrode is weaker than the bending strength of the piezoelectric layer.

Abstract: A thermoelectric module includes a first substrate, a second substrate having a second surface which is apart from and faces a first surface of the first substrate, a plurality of thermoelectric elements arranged on the first and the second surfaces, a plurality of electrodes on the first and second surfaces each electrically connected to at least one of the plurality of thermoelectric elements, and a ground electrode on at least the first surface. The plurality of electrodes on at least the first surface comprises a plurality of columns each of which comprises two or more electrodes aligned in a longitudinal direction, and the ground electrode is between two adjacent columns among the plurality of columns.

Abstract: A ceramic member in which the metal layers with high void ratio are sufficiently sintered to lower a residue of resin is produced. The method for manufacturing a ceramic member which comprises a step of forming a stacked compact from a plurality of metallic paste layers containing a metal component M1 that are stacked one on another via ceramic green sheets, and a step of firing the stacked compact, wherein at least one of plural metallic paste layers is formed as a second metallic paste layer that has the mass percentage X higher than that of the metallic paste layer that adjoin therewith in the stacking direction and a ceramic powder is contained in the second metallic paste layer in the step of forming the stacked compact, the mass percentage X being the proportion of the metal component M1 to the total metal content in the metallic paste layer.

Abstract: To provide a multi-layer piezoelectric device having excellent durability in which the amount of displacement does not change even when the piezoelectric actuator is subjected to continuous operation over a long period of time under a high voltage and a high pressure, the multi-layer piezoelectric device comprises a stack formed by stacking piezoelectric layers and internal electrodes alternately one on another and external electrodes formed on a first side face and on a second side face of the stack, wherein one of the adjacent internal electrodes is connected to the external electrode formed on the first side face and the other internal electrode is connected to the external electrode formed on the second side face, while content of alkali metal in a range from 5 ppm to 300 ppm is contained.

Abstract: This aims to provide a multi-layer piezoelectric element, which is made excellent in durability and suppressed in the reduction of a displacement degree, even if the element is largely displaced or driven at a high speed, and an injection device and a fuel injection system using the element. The multi-layer piezoelectric element comprises a stacked body comprising a plurality of ceramic layers and a plurality of internal electrode layers, each of the plurality of internal electrode layers being sandwiched between ceramic layers of the plurality of ceramic layers that are located opposite to each other. The plurality of ceramic layers comprises a plurality of piezoelectric layers, and a low-rigidity ceramic layer which has a rigidity lower than that of the plurality of piezoelectric layers and that of the plurality of internal electrode layers.

Abstract: Provided is a multi-layer piezoelectric element in which the amount of the positional displacement can be suppressed even when continuous driving is performed for a long time under high electrical field and high pressure, and which may have a good durability. The laminated piezoelectric element comprises a stacked body in which piezoelectric layers and metal layers are stacked alternately one on another. The metal layers comprise internal electrodes and a low-rigidity metal layer which has rigidity lower than those of the piezoelectric layer and the internal electrode. The low-rigidity metal layer comprises a plurality of metal parts isolated from each other via voids, and a covering layer which covers at least a part of the metal parts.

Abstract: A multi-layer piezoelectric element having high durability of which amount of displacement is suppressed from varying even when operated continuously over a long period of time with a higher electric field under a high pressure is provided. The multi-layer piezoelectric element which has a multi-layer structure, the multi-layer structure comprising a plurality of piezoelectric material layers and a plurality of metal layers that are stacked alternately, wherein the piezoelectric material layer is constituted from a plurality of piezoelectric crystal grains, the plurality of metal layers comprise internal electrodes and low-rigidity metal layer that has rigidity lower than those of the internal electrodes and the piezoelectric material layer, and wherein the low-rigidity metal layer has a plurality of metal parts that are separated from each other, and an end of the metal part infiltrates between the piezoelectric crystal grains.

Abstract: A multi-layer piezoelectric element having high durability of which amount of displacement is suppressed from varying even when operated continuously over a long period of time with a higher electric field under a high pressure is provided. The multi-layer piezoelectric element comprising a multi-layer structure in which a plurality of piezoelectric material layers and a plurality of metal layers are stacked alternately one on another, wherein the plurality of metal layers comprises internal electrodes and low-rigidity metal layer that has rigidity lower than those of the piezoelectric material layer and the internal electrode, wherein the low-rigidity metal layer comprises a plurality of metal parts that are separated from each other, and wherein at least one of the metal parts is bonded with only one piezoelectric material layer among the two piezoelectric material layers that adjoin in the stacking direction.

Abstract: The multi-layer piezoelectric element comprises a stack having an active portion constituted from at least one piezoelectric layer and a plurality of internal electrodes consisting of first and second internal electrodes placed one on another, the active portion being subjected to expansion and contraction in response to a voltage applied across the first internal electrode and the second internal electrode, and external electrodes formed on two side faces of the stack with one thereof being connected to the first internal electrode and the other connected to the second internal electrode, wherein each of the external electrodes is constituted from three or more layers including a first layer formed in contact with the side face of the stack and a second layer formed on the first layer, to provide a multi-layer piezoelectric element having high durability.

Abstract: To provide a multi-layer piezoelectric device having excellent durability in which the amount of displacement does not change even when the piezoelectric actuator is subjected to continuous operation over a long period of time under a high voltage and a high pressure, the multi-layer piezoelectric device comprises a stack formed by stacking piezoelectric layers and internal electrodes alternately one on another and external electrodes formed on a first side face and on a second side face of the stack, wherein one of the adjacent internal electrodes is connected to the external electrode formed on the first side face and the other internal electrode is connected to the external electrode formed on the second side face, while content of alkali metal in a range from 5 ppm to 300 ppm is contained.

Abstract: A multi-layer piezoelectric element having high durability which allows it to increase the amount of displacement of a piezoelectric actuator under high voltage and high pressure and does not undergo a change in the amount of displacement during continuous operation in a high electric field and under a high pressure over a long time period is provided. The multi-layer piezoelectric element comprises a stack of at least one piezoelectric layer and a plurality of internal electrodes consisting of first and second internal electrodes placed one on another, a first external electrode formed on a first side face of the stack and connected to the first internal electrode and a second external electrode formed on a second side face of the stack and connected to the second internal electrode, wherein the bonding strength between the piezoelectric layer and the internal electrode is weaker than the bending strength of the piezoelectric layer.

Abstract: Provided is a highly durable laminated piezoelectric element wherein a stress generated at a portion, i.e., the boundary between an active region and inactive region, is reduced. A method for manufacturing such laminated piezoelectric element is also provided. The laminated piezoelectric element has a laminated structure (15) wherein a plurality of piezoelectric layers (11) and internal electrode layers (13) are alternately laminated. The piezoelectric layer (11) contains a metal element other than those elements constituting piezoelectric ceramic, i.e., the main component of the piezoelectric layer (11), and at a portion (11a) of the piezoelectric layer (11) at the vicinity of an end of the internal electrode layer (13), metal particles having a metal element as a main component exist. The content of the metal at the portion (11a) at the vicinity of the end is higher than the content of a compound of the metal element and a nonmetal element.

Abstract: A multi-layer piezoelectric element having high durability which allows it to increase the amount of displacement of a piezoelectric actuator under high voltage and high pressure and does not undergo a change in the amount of displacement during continuous operation in a high electric field and under a high pressure over a long time period is provided. The multi-layer piezoelectric element comprises a stack of at least one piezoelectric layer and a plurality of internal electrodes consisting of first and second internal electrodes placed one on another, a first external electrode formed on a first side face of the stack and connected to the first internal electrode and a second external electrode formed on a second side face of the stack and connected to the second internal electrode, wherein the bonding strength between the piezoelectric layer and the internal electrode is weaker than the bending strength of the piezoelectric layer.