Abstract: A vibration device includes: a piezoelectric unit including a piezoelectric element; a housing that holds the piezoelectric unit; a wiring member electrically connected to the piezoelectric unit; and a joining member that joins the housing to an external device. The housing includes a bottom surface portion to which the piezoelectric unit is fixed, and a side surface portion standing at an edge portion of the bottom surface portion. The side surface portion has a first surface formed on a top portion of the side surface portion, and a second surface that is one step lowered from the first surface by a cutout portion formed in the top portion. The joining member extends along the first surface to bridge over the cutout portion. The wiring member is joined to the joining member at a position of the first surface, and passes through the cutout portion in a state where the wiring member is not joined to the second surface.

Abstract: A vibration device includes: a piezoelectric unit including a piezoelectric element; and a housing made of metal that holds the piezoelectric unit. The housing includes a bottom surface portion to which the piezoelectric unit is fixed, and side surface portions that stand at an edge portion of the bottom surface portion to surround the piezoelectric unit. The side surface portions are continuous with the bottom surface portion, and are inclined to open outward from the edge portion with respect to the bottom surface portion.

Abstract: A vibration device includes a piezoelectric element and a vibration member. The vibration device is arranged to be supported on a base. The vibration member includes a first main surface opposing the base and a second main surface opposing the first main surface. The piezoelectric element is disposed on the second main surface. The first main surface of the vibration member is provided with a protrusion contacting the base and defining a vibration space on the first main surface. The protrusion is positioned outside the piezoelectric element to surround the piezoelectric element when the vibration member is seen through from a direction orthogonal to the first main surface.

Abstract: In an acoustic device, the housing includes a main body portion and a rib portion. The main body portion includes a vibrating portion and a plurality of support portions. The rib portion is connected to the main body portion. The rib portion extends in a third direction between a pair of the support portions facing each other and separated from each other in the third direction intersecting a second direction, when viewed from the second direction along a vibrating surface. A hollow region is defined by the vibrating portion and the plurality of support portions. The above opening is defined by the rib portion and the main body portion and communicates with the hollow region. The rib portion covers the middle of the hollow region when viewed from the second direction.

Abstract: In a vibration device, an operation unit has an operation surface operated by a user. A plurality of piezoelectric elements are disposed so as to overlap the operation surface when viewed from the direction orthogonal to the operation surface. The plurality of piezoelectric elements are disposed at mutually different positions in the direction along the operation surface. A control unit is arranged to control the plurality of piezoelectric elements. The control unit is arranged to vibrate the piezoelectric element corresponding to a first position on the operation surface where an operation is performed at a first frequency and vibrates the piezoelectric element corresponding to a second position on the operation surface different from the first position among the plurality of piezoelectric elements at a second frequency, in response to the operation of the operation surface. The second frequency is a frequency in the audible range.

Abstract: A vibration device includes a piezoelectric element, a vibration member to which the piezoelectric element is bonded, and a wiring member connected with the piezoelectric element. A method for vibrating the vibration device includes inputting a signal including a fundamental frequency component to the piezoelectric element through the wiring member, and vibrating the vibration device in a vibration mode that includes the fundamental frequency component and does not approximately include a high order frequency component that is n times (n represents an integer of 2 or more) the fundamental frequency component. The fundamental frequency component is lower than the resonance frequency component of the vibration device.

Abstract: In a piezoelectric element, shift of a resonance point to a low-pitched sound side is achieved. A resonance point of a piezoelectric element moves to a low-pitched sound side when an active region is configured to be surrounded by an inactive region as in the configuration of the piezoelectric element. According to the piezoelectric element whose resonance point is moved to a low-pitched sound side, the piezoelectric element can realize a sound pressure that is sufficiently high for practical use when it is applied to an acoustic device.

Abstract: An acoustic device includes a piezoelectric element, an attachment member to which the piezoelectric element is attached, and a spacer. The piezoelectric element includes first and second principal surfaces opposing each other. The attachment opposes the first principal surface. The spacer is disposed between the piezoelectric element and the attachment member in such a manner as to form an acoustic space between the piezoelectric element and the attachment member. The spacer includes an adhesive layer including a principal surface in contact with the first principal surface and a principal surface in contact with the attachment member.

Abstract: A vibration device includes a vibration plate, a piezoelectric element, and a wiring member. The vibration plate has conductivity. The piezoelectric element is disposed on the vibration plate. The wiring member is disposed to oppose the vibration plate via the piezoelectric element. The piezoelectric element includes a piezoelectric element body, a first external electrode, and a second external electrode. The piezoelectric element body has a first main surface and a second main surface facing away from each other in an opposing direction of the vibration plate and the wiring member. The first external electrode is disposed on the first main surface and electrically connected to the vibration plate. The second external electrode is disposed on the second main surface and electrically connected to the wiring member. The vibration plate includes a first projection projecting toward the wiring member and electrically connected to the wiring member.

Abstract: An audio device includes a vibration member, and a first piezoelectric vibrator and a second piezoelectric vibrator that are provided on the vibration member. A natural frequency of the first piezoelectric vibrator is larger than a natural frequency of the second piezoelectric vibrator.

Abstract: A piezoelectric element includes a piezoelectric element body, a first external electrode disposed on a first main surface of the piezoelectric element body, and a second external electrode disposed on a second main surface of the piezoelectric element body. A vibration member includes an electrically conductive third main surface and a fourth main surface opposing the third main surface. The vibration member is disposed such that the third main surface opposes the first external electrode. A protective layer covers the piezoelectric element. The protective layer includes a first resin layer and a second resin layer. The first resin layer covers the piezoelectric element body and the second external electrode. The second resin layer is disposed between the first external electrode and the third main surface and joins the first external electrode and the third main surface. The first resin layer is smaller in hardness than the second resin layer.

Abstract: A vibration device includes a piezoelectric element and a vibration member. The vibration device is arranged to be supported on a base. The vibration member includes a first main surface opposing the base and a second main surface opposing the first main surface. The piezoelectric element is disposed on the second main surface. The first main surface of the vibration member is provided with a protrusion contacting the base and defining a vibration space on the first main surface. The protrusion is positioned outside the piezoelectric element to surround the piezoelectric element when the vibration member is seen through from a direction orthogonal to the first main surface.

Abstract: A vibrating device includes a piezoelectric element, a resin member having electric insulation, a vibrating member made of metal, a first adhesive layer, and a second adhesive layer. The resin member includes a first principal surface and a second principal surface opposing each other. The vibrating member includes a third principal surface and a fourth principal surface opposing each other. The first adhesive layer joins the piezoelectric element and the first principal surface. The second adhesive layer joins the second principal surface and the third principal surface. An area of the resin member is greater than an area of the piezoelectric element, and an area of the vibrating member is greater than the area of the piezoelectric element. An area where the second adhesive layer adheres to the vibrating member is greater than an area where the first adhesive layer adheres to the resin member.

Abstract: A vibrating device includes a piezoelectric element, a wiring board electrically connected with the piezoelectric element, and a diaphragm including a metal. The piezoelectric element and the wiring board are bonded to the diaphragm. The piezoelectric element includes a piezoelectric element body, a plurality of internal electrodes, and a plurality of external electrodes. The piezoelectric element body has a first principal plane and a second principal plane opposed to each other. The plurality of internal electrodes is disposed in the piezoelectric element body. The internal electrodes are opposed to each other in a direction in which the first principal plane and the second principal plane are opposed. The plurality of external electrodes is disposed on the first principal plane, and is electrically connected with corresponding internal electrodes, of the plurality of internal electrodes. The wiring board has a resin film and a plurality of conductors.

Abstract: An acoustic device includes a piezoelectric element, an attachment member to which the piezoelectric element is attached, and a spacer. The piezoelectric element includes first and second principal surfaces opposing each other. The attachment opposes the first principal surface. The spacer is disposed between the piezoelectric element and the attachment member in such a manner as to form an acoustic space between the piezoelectric element and the attachment member. The spacer includes an adhesive layer including a principal surface in contact with the first principal surface and a principal surface in contact with the attachment member.

Abstract: A vibration device includes a piezoelectric element and an adhesive layer. The piezoelectric element includes a first principal surface and a second principal surface opposing each other. The adhesive layer is disposed on the first principal surface and is in contact with the first principal surface. A tensile strength of the adhesive layer is 10 N/cm or more and 48 N/cm or less.

Abstract: A vibrating device includes a diaphragm, a piezoelectric element, and a wiring board. The piezoelectric element and the wiring board are bonded to a first principal plane of the diaphragm. The wiring board is electrically connected with the piezoelectric element. The piezoelectric element includes a piezoelectric element body, a plurality of internal electrodes, and a plurality of external electrodes. The piezoelectric element body has a second principal plane, a third principal plane, and a side surface. The third principal plane and the side surface are bonded to the first principal plane. The wiring board has a resin film, a plurality of conductors, and a coating film. The coating film is disposed on the plurality of conductors in such a way as to cover the plurality of conductors. One end portions of the plurality of conductors are exposed from the coating film and electrically connected with corresponding external electrodes.