Abstract: An acoustic generator according to an embodiment at least includes an exciter, a vibrating plate, and a frame body. The exciter is caused to vibrate by an electrical signal. The exciter is mounted on the vibrating plate, and the vibrating plate is caused to vibrate together with the exciter by the vibration of the exciter. The frame body is provided on the outer peripheral portion of the vibrating plate. The frame body includes two frame members having different thicknesses or widths, and the two frame members nip the vibrating plate to support the vibrating plate.

Abstract: A multi-layer piezoelectric element includes a stacked body in which piezoelectric layers and internal electrode layers are alternately laminated and a stress relaxing layer is disposed at part of portions between the piezoelectric layers, and an external electrode that is bonded to a side face of the stacked body so as to make electrical connection with the internal electrode layers, the internal electrode layers being not exposed on the side face of the stacked body, but the stress relaxing layer being exposed on the side face of the stacked body.

Abstract: An object is to flatten a frequency characteristic. For achieving the object, an acoustic generator according to an embodiment includes a piezoelectric element (exciter) and a film (film-like vibrating body). The piezoelectric element receives input of an electric signal and vibrates. The piezoelectric element is bonded to the film through a bonding material and the film vibrates together with the piezoelectric element with the vibration of the piezoelectric element. Furthermore, the acoustic generator in the embodiment has voids in the bonding material.

Abstract: A purpose is to obtain a frequency characteristic of a good sound pressure. To achieve the purpose, an acoustic generator according to an embodiment includes a piezoelectric element (exciter), a flat vibrating body, and a resin layer. The piezoelectric element vibrates when an electric signal is input. To the vibrating body, the piezoelectric element is attached. The vibrating body vibrates with the piezoelectric element due to the vibration of the piezoelectric element. The resin layer is arranged to cover surfaces of the piezoelectric element and the vibrating body to which the piezoelectric element is attached. The resin layer is integrated with the vibrating body and the piezoelectric element. Also, to the resin layer, irregularity is provided.

Abstract: To provide an acoustic generator, an acoustic generation device, and an electronic apparatus including an exciter which vibrates by an electric signal being input, and being capable of suppressing a peak dip and flattening frequency characteristics. To solve the problem, an acoustic generator disclosed herein includes: an exciter which vibrates by an electric signal being input; and a film-shaped vibrating body to which the exciter is bonded via a bonding material and which vibrates together with the exciter by the vibration of the exciter, wherein the bonding material has a protruded part which protrudes from an outer edge of the exciter when the vibrating body is viewed in plane, and at least a part of the protruded part has an undulating shape.

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, the mass percentage X being the proportion of the metal component M1 to the total metal content in the metallic paste layer.

Abstract: A multi-layer piezoelectric element includes a stacked body configured so that piezoelectric layers and internal electrode layers are alternately laminated, and an external electrode composed of a sintered material of both electrically conductive particles and a glass, the external electrode which is bonded to a side surface of the stacked body and makes electrical connection with the internal electrode layers. The external electrode has a stacked body-side layer region containing glass as secondary constituent at its stacked body-facing side, and an exterior-side layer region containing glass as minor constituent at its exterior side. The glass of the exterior-side layer region is distributed along grain boundary of the conductive particles on an outermost surface of the exterior-side layer region.

Abstract: A piezoelectric actuator includes a stacked body composed of internal electrodes and piezoelectric layers which are stacked on each other; and a surface electrode disposed on at least one of main surfaces of the stacked body so as to be electrically connected to the internal electrodes. The internal electrodes each includes a first electrode and a second electrode. The stacked body has an active section in which the first electrodes and the second electrodes of the internal electrodes are arranged so as to overlap each other in a stacking direction thereof, and an inactive section which is every section of the stacked body other than the active section. An internal electrode placed on a one-main-surface side of the internal electrodes is configured so that its end part situated near a boundary between the active section and the inactive section is curved toward the other main surface.

Abstract: A piezoelectric actuator, a piezoelectric vibration apparatus and a portable terminal are disclosed. The actuator includes a piezoelectric element, a flexible substrate and a bonding layer. The piezoelectric element includes a laminate in which inner electrodes and piezoelectric layers are alternatively stacked; and surface electrodes on a first main surface of the laminate, each electrically connected to some of the inner electrodes, respectively. The flexible substrate includes a wiring conductor that is electrically connected to the surface electrodes. The bonding layer is located between a part of flexible substrate and the first main surface. At least a region, where the flexible substrate is bonded, of the first main surface has a flatness worse than a flatness of an second main surface which is opposed to the first main surface.

Abstract: A piezoelectric actuator includes a stacked body composed of internal electrodes and piezoelectric layers which are stacked on each other; and a surface electrode disposed on at least one of main surfaces of the stacked body so as to be electrically connected to the internal electrodes. The internal electrodes each includes a first electrode and a second electrode. The stacked body has an active section in which the first electrodes and the second electrodes of the internal electrodes are arranged so as to overlap each other in a stacking direction thereof, and an inactive section which is every section of the stacked body other than the active section. An internal electrode placed on a one-main-surface side of the internal electrodes is configured so that its end part situated near a boundary between the active section and the inactive section is curved toward the other main surface.

Abstract: An acoustic generator according to an embodiment includes a vibrating body and an exciter. The exciter is provided on the vibrating body, and vibrates by an input of an electrical signal. The exciter includes a protrusion or a recess on/in a surface of a side of the vibrating body.

Abstract: An acoustic generator according to an embodiment is provided with a vibration body, an exciter (piezoelectric vibration element), and a coating portion. The exciter is joined onto the vibration body through a joining portion. The coating portion is provided from the exciter to the vibration body. Furthermore, at least a part of an outer periphery of the joining portion is positioned inside of an outer periphery of the exciter, and a part of the coating portion is interposed between the vibration body and the exciter.

Abstract: An acoustic generator includes a vibrating body. The acoustic generator includes a frame member attached by a bonding material to an external peripheral portion of the vibrating body. The acoustic generator has an exciter provided on the vibrating body inside of the frame member. In this case, the acoustic generator further includes an extended portion of the bonding material provided to be extended on the vibrating body inside of the frame from the frame member.

Abstract: An object is to provide a preferable frequency characteristic of a sound pressure. For achieving the object, an acoustic generator according to an embodiment includes a piezoelectric element (exciter), a flat vibration plate, and a frame body. The piezoelectric element receives input of an electric signal and vibrates. The piezoelectric element is attached to the vibration plate, and the vibration plate vibrates together with the piezoelectric element with the vibration of the piezoelectric element. The frame body is provided on an outer circumferential portion of the vibration plate. Corners on an inner circumferential surface of the frame body include at least curved surfaces, and at least one of the corners has a shape different from the shape of the other corners.

Abstract: A rotor is provided for a rotating electric machine. The rotor includes a magnetic pole core and a cooling fan. The cooling fan includes a base plate laser-welded to an axial end face of the magnetic pole core and a plurality of fan blades extending from the base plate. Further, in the rotor, a weld formed between the base plate of the cooling fan and the magnetic pole core has a pair of open ends.

Abstract: An object is to flatten a frequency characteristic. For achieving the object, an acoustic generator according to an embodiment includes a piezoelectric element (exciter) and a film (film-like vibrating body). The piezoelectric element receives input of an electric signal and vibrates. The piezoelectric element is bonded to the film through a bonding material and the film vibrates together with the piezoelectric element with the vibration of the piezoelectric element. Furthermore, the acoustic generator in the embodiment has voids in the bonding material.

Abstract: A stator for an electric rotating machine includes a stator core which has a plurality of slots and a stator winding which is provided at the stator core. The stator winding has a plurality of conductor segments each of which includes an inner conducting body accommodated in the slot of the stator core and coil ends exposed from the slot, and weld portions which are connected with each other by welding the conductor segments at at least one of the coil ends. The weld portions are annularly disposed with an interval therebetween. The weld portions are coated with an insulating resin material. The resin material is formed of a plurality of layered insulating films.

Abstract: There are provided a multi-layer piezoelectric element in which an increase of oxygen vacancies in an electric-field concentration part of piezoelectric layers is suppressed and a decrease of an amount of displacement is suppressed, as well as to provide a piezoelectric actuator, an injection device and a fuel injection system provided with the multi-layer piezoelectric element. A multi-layer piezoelectric element includes a stacked body composed of piezoelectric layers and internal electrode layers which are stacked on each other, and a resin which evolves OH? when being heated. Accordingly, it is possible to obtain a multi-layer piezoelectric element in which an increase of oxygen vacancies in an electric-field concentration part of piezoelectric layers is suppressed and a decrease of an amount of displacement is suppressed.

Abstract: Provided is a highly durable multi-layer piezoelectric element wherein a conductive connection member is not broken even in the case of continuous driving for a long period in a high electric field under high pressure. A multi-layer piezoelectric element includes a stacked body configured so that piezoelectric layers and internal electrode layers are alternately laminated, an external electrode bonded to a side surface of the stacked body and electrically connected to the internal electrode layers, and a conductive connection member which is disposed on a surface of the external electrode and of which surface has projections and depressions formed repeatedly at least in a stacked direction of the stacked body.

Abstract: In a current measuring device for measuring an electric current flowing through between a terminal of a battery and a wire, a resistance member has a length and first and second ends in a direction of the length. The first end is to be secured electrically to the terminal of the battery. The second end is to be secured electrically to the wire. The resistance member constitutes a current flow path between the terminal of the battery and the wire. The resistance member has a turned portion through which the current flow path extends. The current measuring device includes a circuit board in which a current measuring circuit is installed. The current measuring circuit measures an electric current flowing through the resistance member based on a potential difference between two different points defined on the resistance member.