A pumping mechanism in accordance with the present invention is used with a pneumatic tire mounted on a wheel to keep the pneumatic tire from becoming underinflated. The pumping mechanism includes a frame having a first chamber and a pump chamber, a strike plate positioned in the first chamber and being connected to a plunger plate, said plunger plate having a nose for engagement with a diaphragm mounted in the pump chamber; said pump chamber being in fluid communication with a pump inlet and a pump outlet; wherein actuation of the strike plate in the first chamber causes engagement of the nose with the diaphragm. Preferably the strike plate is actuated by a permanent magnet mounted on a stationary part, or the strike plate is actuated by an electrically driven magnet.

A pump apparatus includes a piezoelectric pump, an outer housing, and an adhesive sheet. The piezoelectric pump has a principal surface at which a discharge port for a fluid is formed. The outer housing has a housing channel that communicates with the discharge port, and the outer housing is formed at least partially using a resin having water-containing properties. The adhesive sheet adheres the principal surface of the piezoelectric pump to the outer housing. The outer housing includes a main plate. The main plate has a principal surface that opposes the principal surface of the piezoelectric pump and is in contact with the adhesive sheet. The main plate also has a through-hole that communicate with the discharge port and with the housing channel. The principal surface is formed as a surface of a metal portion.

The invention relates to a device having an opening defining a fluid connection between a fluid channel in the device and ambient air, a sensor coupled to the fluid channel, configured to sense at least one component of the ambient air, and a micro fluid actuator connected downstream of the sensor, configured, in the suction stroke, to suck in fluid through the fluid channel and to transport the same towards the sensor, and, in the pressure stroke, to transport the sucked-in fluid through said fluid channel back towards the opening. According to the invention, the sensor is arranged spaced apart from the opening, and the volume of the fluid channel between the sensor and the opening is equal to or smaller than the stroke volume which the micro fluid actuator may convey with a single suction stroke.

A valve includes a lower valve housing, a diaphragm, and an upper valve housing. A top surface of a piezoelectric pump is bonded to a bottom surface of the lower valve housing. A circular hole portion is provided in a central portion of a region of the diaphragm that opposes a projecting portion of the lower valve housing. The diaphragm is bonded to the upper valve housing and the lower valve housing, and a divided interior of a valve housing configures a first lower valve chamber, a second lower valve chamber, a first upper valve chamber, and a second upper valve chamber. A groove is located in a wall portion of the upper valve housing that opposes the diaphragm in the first upper valve chamber.

A piezoelectric actuator includes a square suspension plate, an outer frame, plural brackets and a square piezoelectric ceramic plate. The outer frame is arranged around the suspension plate. A second surface of the outer frame and a second surface of the suspension plate are coplanar with each other. The plural brackets are perpendicularly connected between the suspension plate and the outer frame for elastically supporting the suspension plate. Each bracket has a length in a range between 1.11 mm and 1.21 mm and a width in a range between 0.2 mm and 0.6 mm. A length of the piezoelectric ceramic plate is not larger than a length of the suspension plate. The piezoelectric ceramic plate is attached on a first surface of the suspension plate.

A method of regulating pressure inside a prosthetic socket includes measuring pressure inside of a prosthetic socket using one or more sensors operatively coupled to a pump system to obtain pressure information associated with an inside of the prosthetic socket. The pump system has a pump mechanism in fluid communication with the inside of the prosthetic socket. The method involves actuating the pump mechanism without human intervention to regulate vacuum inside of the prosthetic socket based on the pressure information.

A gas transportation device is provided and includes a plurality of flow guiding units. Each of the flow guiding units includes an inlet plate, a substrate, a resonance plate, an actuating plate, a piezoelectric component, an outlet plate and a valve, which are sequentially stacked. A convergence chamber is formed between the resonance plate and the inlet plate. The actuating plate has a suspension part, an outer frame and a plurality of interspaces. The piezoelectric component is attached on a surface of the suspension part. Gas is inhaled into the convergence chamber via an inlet aperture of the inlet plate, is transported into a first chamber via a central aperture of the resonance plate, is further transported into a second chamber via the interspaces, and is discharged out from an outlet aperture of the outlet plate. The gas is transported by the flow guiding units disposed in a specific arrangement.

A valve includes a lower valve housing, a diaphragm, and an upper valve housing. A top surface of a piezoelectric pump is bonded to a bottom surface of the lower valve housing. A circular hole portion is provided in a central portion of a region of the diaphragm that opposes a projecting portion of the lower valve housing. The diaphragm is bonded to the upper valve housing and the lower valve housing, and a divided interior of a valve housing configures a first lower valve chamber, a second lower valve chamber, a first upper valve chamber, and a second upper valve chamber. A groove is located in a wall portion of the upper valve housing that opposes the diaphragm in the first upper valve chamber.

A vacuum suspension system includes a prosthetic socket adapted to receive a residual limb. A pump system includes a pump mechanism in fluid communication with the prosthetic socket, and at least one sensor associated with the prosthetic socket and/or the pump mechanism. A control system is operably connected to the pump mechanism and the least one sensor. The control system is arranged to receive and process data from the at least one sensor and to actuate the pump mechanism based on the received data from the at least one sensor.

Provided is a high frequency oscillating ventilator comprising a housing assembly, a linear actuator, a linear coil, a piston mounted on a pushrod, a diaphragm dividing a housing into a first and second side and having an opening formed on the second side that is fluidly connected to the patient's airway for delivering gas thereto. The linear actuator is fixedly mounted to the housing assembly and has a linear coil coaxially disposed therewithin. A pushrod supports the linear coil on the linear actuator to allow relative axially sliding therebetween. The piston is directly mounted to the diaphragm such that reciprocation thereof as effectuated by the linear coil cooperating with the linear actuator alternately produces positive and negative pressure waves in the gas in the patient's airway.