Abstract: An actuator includes a main plate, a frame, a connection member, and a piezoelectric element. The main plate has a principal surface and a principal surface and has a rotationally symmetrical shape as viewed in plan. The frame is disposed at a position outside a peripheral edge of the main plate. The connection member is connected to the peripheral edge of the main plate and to the frame. The connection member holds the main plate so as to enable the main plate to vibrate relative to the frame. The piezoelectric element is disposed on the principal surface of the main plate, and the circumferential shape of the piezoelectric element is smaller than the main plate. The main plate includes a recess and a thin portion in a region that includes a center and a peripheral edge of the main plate and that overlaps the piezoelectric element as viewed in plan.

Abstract: A pump device includes a piezoelectric pump, a piezoelectric pump, and a connection pipe. The connection pipe causes a discharge port of the piezoelectric pump to be in communication with a suction port of the piezoelectric pump. The piezoelectric pump and the piezoelectric pump are disposed such that a suction-side outer wall surface in a housing of the piezoelectric pump and a suction-side outer wall surface in a housing of the piezoelectric pump face each other.

Abstract: A first main plate has a first principal surface and a second principal surface. A second main plate has a third principal surface, a fourth principal surface, and an aperture. A piezoelectric element is provided on the first main plate and vibrates the first main plate. A first frame is disposed outside an outer peripheral end of the first main plate. First connecting portions connect the first main plate and the first frame to each other. Apertures are formed between the first connecting portions and connect a space adjacent to the first principal surface and a space adjacent to the second principal surface to each other. The second frame is disposed outside an outer peripheral end of the first frame. A second connecting portion connects the first frame and the second frame to each other.

Abstract: A fluid control device includes a pump and an outer housing containing the pump. The outer housing has a first outer wall that forms an internal space on a flat plate side of the pump and that has a through hole allowing the internal space and an external space to communicate with each other. The first outer wall includes an outer wall main plate facing a piezoelectric element, and a side plate that is connected to the outer wall main plate and that has the through hole. The outer wall main plate has a higher thermal conductivity than that of a second outer wall.

Abstract: A fluid control device has a housing. A first main plate of the housing includes a vibration portion, on which a drive body is disposed, having a rotationally symmetric shape in plan view, and multiple openings which is formed outside the vibration portion and through which a pump chamber and the outside communicate with each other. A second main plate includes an opening through which the pump chamber and the outside communicate with each other and which has a rotationally symmetric shape in plan view. The opening is arranged to include the center of the vibration portion in plan view of the first main plate and the second main plate. An opening area of the opening is from 10% to 75% of an area of the vibration portion.

Abstract: A fluid control device includes a fluid conveying element formed by a pump and a valve, and an outer housing containing the fluid conveying element. The outer housing includes a first outer wall forming an internal space closer to the pump, and a second outer wall forming an internal space closer to the valve. The second outer wall includes an outer-wall main plate having a part overlapping, in plan view, a through hole that is a discharge hole of the valve. A thermal conductivity of the part of the outer-wall main plate overlapping the discharge hole is higher than a thermal conductivity of the first outer wall.

Abstract: A first main plate has a first principal surface and a second principal surface. A second main plate has a third principal surface, a fourth principal surface, and an aperture. A piezoelectric element is provided on the first main plate and vibrates the first main plate. A first frame is disposed outside an outer peripheral end of the first main plate. First connecting portions connect the first main plate and the first frame to each other. Apertures are formed between the first connecting portions and connect a space adjacent to the first principal surface and a space adjacent to the second principal surface to each other. The second frame is disposed outside an outer peripheral end of the first frame. A second connecting portion connects the first frame and the second frame to each other.

Abstract: An actuator includes a frame, a central flat plate and connecting members. The frame has a regular square opening. The central flat plate has a circular shape and is disposed inside the regular square opening. A driving device is attached to the central flat plate. The connecting members are disposed inside the regular square opening at a position between the central flat plate and the frame. The connecting members connect the central flat plate and the frame. Each connecting member includes a first portion and a second portion. The first portion extends in a radial direction extending outward from the center of the central flat plate. The first portion is connected to the central flat plate and to the second portion. The second portion extends in a direction different from the extending direction of the first portion.

Abstract: A fluid control device includes a first main plate, a second main plate, a driving body, a frame body, a plurality of support bodies, a plurality of gaps, a side wall member, a valve film, and a fixing member. A pump chamber is formed by a flat plate part consisting of the first main plate, the frame body, and the plurality of support bodies, and the second main plate and the side wall member. The valve film is disposed on a main surface of the first main plate on the side where the pump chamber is located. The valve film has an annular shape and fixed to the first main plate by the fixing member so that an outer end thereof is a movable end. The outer end of the valve film overlaps the plurality of gaps located between the plurality of support portions in plan view.

Abstract: An actuator includes a first main plate at which a piezoelectric element is disposed, a frame body, and a connection part. The frame body is disposed on an outer side of an outer edge of the first main plate and apart from the first main plate. The connection part is disposed between the first main plate and the frame body. The connection part has a plurality connection bodies and a gap, which are disposed along the outer edge, the plurality of connection bodies being connected to the first main plate and the frame body, the gap being disposed between the plurality of connection bodies. The first main plate and the connection bodies are made of the same material. A thickness of the connection bodies is more than a thickness of the first main plate.

Abstract: A fluid control apparatus includes a first major plate, a piezoelectric device, a second major plate, a peripheral plate, a first film, and a second film. The first film is provided on a side of the first major plate that faces a pump chamber. The first film is provided on a first major surface in such a manner as to have a movable portion one end of which serves as a movable end. The second film is provided on a side of the second major plate that faces the pump chamber. The second film is provided on a third major surface in such a manner as to have a movable portion one end of which serves as a movable end. The first film and the second film are positioned between a first opening provided in the first major plate and a second opening provided in the second major plate.

Abstract: A first main plate has a first principal surface and a second principal surface. A second main plate has a third principal surface, a fourth principal surface, and an aperture. A piezoelectric element is provided on the first main plate and vibrates the first main plate. A first frame is disposed outside an outer peripheral end of the first main plate. First connecting portions connect the first main plate and the first frame to each other. Apertures are formed between the first connecting portions and connect a space adjacent to the first principal surface and a space adjacent to the second principal surface to each other. The second frame is disposed outside an outer peripheral end of the first frame. A second connecting portion connects the first frame and the second frame to each other.