A linear compressor includes a cylinder that defines a compression space for a refrigerant, a frame that fixes the cylinder to a shell, a piston that axially reciprocates in an interior of the cylinder, a discharge valve that is provided in front of the cylinder to selectively discharge the refrigerator compressed in the compression space for the refrigerant, a discharge cover that is coupled to the frame and has a discharge space for the refrigerant discharged through the discharge valve, a valve spring that provides an axial resilient force to the discharge valve while supporting the discharge valve, and a valve support device that is coupled to the valve spring and supported by the frame to deliver vibration generated by the discharge valve to the frame.

A one-way valve device for air compressors including a disc-shaped element having a plurality of holes for flow of the air distributed along a portion having a circular crown extension, a sheet superposed on the disc-shaped element for occluding the holes, the sheet being susceptible to lifting due to the pushing action exerted by the air flowing through the holes, a spring opposing the lifting of the sheet, a containment and covering dome.

An air flow generating device includes an enclosing wall, a frame sheet, a cover film, and a vibrating part. The frame sheet is disposed inside an air flow passage formed by the enclosing wall and closely contacts the air flow passage by its periphery. The cover film includes a central connection portion fixed to a central portion of the frame sheet, and a plurality of movable cover portions connected to the central connection portion. The cover film is between the frame sheet and an outlet of the air flow passage. The movable cover portions selectively cover a plurality of through holes of the frame sheet. The vibrating part is fixed on the frame sheet. When the vibrating part vibrates, the central portion and the central connection portion move together with the vibrating part so that the movable cover portions seal the through holes or move relative to the through holes.

A valve includes a first plate, a side wall plate, a second plate, and a third plate. The first plate has a plurality of first vent holes. The second plate constitutes a valve chamber along with the first plate and the side wall plate. The second plate includes a second principal surface opposing a first principal surface of the first plate. The second plate has a plurality of second vent holes. The third plate has a plurality of third vent holes. The plurality of third vent holes overlaps with the plurality of first vent holes without overlapping with the plurality of second vent holes in a plan view in a direction in which the first plate and the second plate oppose each other. Both principal surfaces of the third plate oppose the first principal surface and the second principal surface. The third plate is disposed in the valve chamber.

The discharge valve arrangement (17) includes a valve plate (18) including a discharge passage (22) and a valve seat (23) surrounding the discharge passage (22); a valve housing (24) being secured to the valve plate (18) and including a bottom portion (25) facing away from the valve plate (18), a sidewall (26) extending from the bottom portion (25) and towards the valve plate (18), and a discharge opening (28) formed in the sidewall (26); a valve member (31) displaceable between a closed position in which the valve member (31) closes the discharge passage (22) and an open position in which the valve member (31) opens the discharge passage (22). The valve housing (24) includes a gas damping chamber defined by the bottom portion (25) and the sidewall (26) and being configured to accommodate the valve member (31) in the open position; and an exhaust opening (37) formed in the bottom portion (25) and emerging in the gas damping chamber.

A check valve with improved response time comprises a valve member which has a central portion of a substantially convex shape and a guide portion that surrounds the central portion. The central portion has a central convex curvature extending towards the outlet port of the check valve, in the direction of the fluid flow. The guide portion has a weight to area ratio that is smaller than the weight to area ratio of the central portion. Such a check valve has an overall reduced weight of the valve member allowing a faster response time when the valve switches between its closed and open positions.

A fluid system includes a fluid active region, a fluid channel, a convergence chamber and plural valves. The fluid active region includes at least one fluid-guiding unit enabled to transport fluid and the fluid is discharged out through an outlet aperture of the fluid active region. The fluid channel is in communication with the outlet aperture, and includes plural branch channels. The convergence chamber is in communication with the fluid channel. Each valve includes a base, a piezoelectric actuator and a linking bar. When the piezoelectric actuator is enabled, the carrier plate is driven to move, and the stopping part of the linking bar is correspondingly moved to selectively close or open an outlet of the base. Each valve is disposed in the corresponding branch channel, and the fluid is selectively transported through the branch channels under control of the on/off states of the valves disposed therein.

A particle filled neck brace is used for immobilizing the neck of a patient and includes a single handedly operable vacuum hand pump disposed on the neck brace, which pump is communicated to the interior of the neck brace. After the neck brace is secured around the neck of the patient, the vacuum hand pump is manipulated to remove air from the neck brace to form a rigid mold about the patient's neck. The vacuum hand pump has a one way directional valve so that the neck brace remains in a rigid configuration for as long as the neck brace is applied to the patient. The vacuum hand pump also includes a plurality of springs which assist the user in completing a vacuum pump cycle. To release the neck brace, the user opens a release valve which allows ambient air to refill the neck brace and increase its flexibility.

An apparatus and method for sensing the position of a piston in a valve in a gas compressor or the position of a piston in a free piston engine. The apparatus includes a plurality of valve sensors, a plurality of magnets, and a plurality of valve sense modules coupled to the valve sensors and a controller coupled to the plurality of valve sense modules. The method includes processing information received from the valve sensors to determine the linear position of the valves in the gas compressor or a piston in a free piston engine.

A linear compressor is provided. The linear compressor may include a cylinder that defines a compression space for a refrigerant; a piston that axially reciprocates inside the cylinder; a motor configured to provide a drive force to the piston; a discharge valve configured to discharge the refrigerant compressed in the compression space; and a discharge cover having a discharge space in which the refrigerant discharged through the discharge valve flows. The discharge valve and the discharge cover may be arranged inside the motor.