One or more techniques and/or systems are disclosed for a flap valve in a diaphragm pump. The flap valve includes a body and a self-centering hinge portion. A front portion of the body includes a front surface having a raised portion and a recessed portion. The front surface is configured to form a seal with a surface of the pump when the body is in a closed position, the surface of the pump being at an inlet or an outlet of a pumping chamber. The body is configured to allow a downstream flow of a fluid when the flap valve is in an open position. The self-centering hinge portion is operably connected to the body. The self-centering hinge portion has a dynamically changing longitudinal axis. The body is configured to simultaneously translate and rotate about the dynamically changing longitudinal axis to form the seal.

A pump for a microfluidic device is disclosed. The pump comprises an actuator and a resilient isolator which is a planar, layered structure. The resilient isolator may comprise a support layer and optionally other layers for strengthening against tensile stress imposed by bending. Alternatively or in addition, the resilient isolator may comprise a plurality of annular regions, layers of the resilient isolator being configured such that at least one of the plurality of annular regions is less resistant than another one of the plurality of annular regions to bending. The actuator may comprise a piezoelectric disc including a surface which comprises electrode regions for electrical connection with respective conductive regions of a conductive layer of the resilient isolator, and an alignment feature for rotational alignment of the piezoelectric disc to ensure the electrical connection between the electrode regions and the respective conductive regions.

A diaphragm pump includes a valve seat, a head cover covered on the valve seat, and a pair of valve plates. A surface of the valves seat is formed concavely with a first receiving trough with a first flow passage, and a second receiving trough with a second flow passage. One of the valve plates is disposed in the first receiving trough, and the other one is disposed in the second receiving trough. The first and second receiving troughs respectively have a geometric shape corresponding with that of the valve plate. The valve plate has a sealing part, and at least one extending arm extended outwardly from the sealing part. The sealing part has a geometric shape being bilaterally symmetrical. The extending arm has an arced end. A gap is existed between an edge of the valves plate and the first receiving trough or the second receiving trough.

A cylinder head cover for a coolant compressor, wherein the cylinder head cover is attachable to a cylinder head arrangement in order to form a hollow space for receiving a coolant compressed by the piston, wherein the cylinder head arrangement comprises a valve plate attached to the cylinder housing and having an outlet opening and an outlet valve, which closes the outlet opening in cycles and consists of a valve spring and a stop plate for delimiting an opening movement of the valve spring. In order to achieve a cost-efficient production and installation of the cylinder head cover while assuring a secure support of the stop plate, it is provided that the cylinder head cover can comprise at least two contact surfaces for supporting stop plates of different outlet valves in order to adjust different opening positions of the valve springs of the different outlet valves.

A reciprocating compressor includes a piston slidably mounted within a compression chamber and defining a suction port. A valve selectively permits a flow of gas through the suction port and includes a sealing portion positioned over the suction port, an attachment portion mechanically coupled to a compression face of the piston, a support portion that extends away from the attachment portion along the radial direction such that the attachment portion is positioned between the sealing portion and the support portion, wherein the support portion defines a flattened end opposite the sealing portion along the radial direction such that the valve has a non-circular shape, and a connecting portion that mechanically couples the support portion to the sealing portion and permits the sealing portion to move between an open position and a closed position.

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.

A piston of an air compressor is actuated by a motor to move in a cylinder. The piston includes a head, an air stop sheet having a first bending section which is a boundary line of an acting area and a positioning zone of the air stop sheet, and a back surface of the acting zone backing the top of the cylinder bends relative to a plane of a top of the head at an open angle. The acting zone has a noncircular spacing groove, a neck, and a second bending section. The head includes a piston rod having a cavity, an air conduit, a column, and a spring. The air stop sheet is forced by the spring to locate in the acting zone backing the cylinder and a plane of a top of the head at an open angle.

A valve assembly (10) including first and second housing parts (22, 24). The first and second housing parts are secured to each other such that respective channels in each are aligned to define inlet and outlet fluid pathways (25, 35) through the valve assembly. A leaf valve insert (38) is arranged between the first and second housing parts, and includes a plurality of leaves (40). First and second leaves are respectively aligned with the inlet and outlet fluid pathways. The first leaf (40a) is configured to permit fluid flow in the inlet fluid pathway in a first direction while impeding fluid flow in a second direction. The second leaf (40b) is configured to permit fluid flow in the outlet fluid pathway in the second direction while impeding fluid flow in the first direction. The first direction is from the first housing part toward the second, and the second direction is from the second housing part toward the first.

A self-suction tail plug includes a detachable tail plug body that has a cylindrical structure. The detachable tail plug body is disposed at a bottom of an air blower. A suction cup is disposed at a bottom of the detachable tail plug body and is configured to adsorb and fix the air blower on a surface of an object. An outer wall at a top of the detachable tail plug body is provided with a fixed protrusion ring engaged with the bottom of the air blower, and the suction cup and the air blower are hermetically connected, such that a sealing protrusion ring is circumferentially disposed on the outer wall of the detachable tail plug body, and the sealing protrusion ring is hermetically connected to the bottom of the air blower.

A diaphragm pump with at least one pump chamber, the pump chamber being connected to an inlet chamber via an inlet valve and to an outlet chamber via two outlet valves. The inlet valve having an inlet opening that can be closed by an inlet valve body and the outlet valve respectively having an outlet opening that can be closed by an outlet valve body. The two outlet valves and the inlet valve form a triangle in a projection onto a projection plane transverse to the longitudinal axis of the pump chamber.