The invention discloses a tilting disc check valve, which includes a left valve body (1), a right valve body (2), a large valve plate (3), a small valve plate (4) and a diaphragm control group (5), wherein the left valve body (1) and the right valve body (2) are butted into a whole through oblique openings; the oblique openings are inclined in a manner that upper parts are inclined towards the right valve body (2); the diaphragm control group (5) is arranged on the left valve body (1); the large valve plate (3) is arranged along the oblique openings; the large valve plate (3) is positioned in a valve cavity formed by the left valve body (1) and the right valve body (2); the large valve plate (3) is suspended on shaft holes of the left valve body (3) through valve shafts (6); the small valve plate (4) is connected with the diaphragm control group (5); and the small valve plate (4) is mounted at a slow closing valve port of the large valve plate (3) through a small valve plate pin shaft (7). According to the tilting disc check valve, a two-stage valve closing process where the large valve plate is quickly closed and the small valve plate at a drain hole of the large valve plate is slowly closed within adjustable time can be implemented, and the aims of reducing backflow of a water body and eliminating pump starting and stopping water hammer are fulfilled.

The invention relates to a valve (10) for controlling the internal pressure p in a cabin of an aircraft, comprising a first flap (11) and a second flap (12), wherein the flaps (11, 12) control a pressure-changing fluid flow (L) between the surroundings and the cabin through an opening (15) of a limiting element (14) of the cabin. In order to increase the inflow volume of the fluid, according to the invention at least one of the flaps (11, 12) is adjustable in the inflow position in respect of the opening (15) in the direction of the surroundings, such that the flow surface of the flap (11, 12) is increased for the air flow (L). Furthermore according to the invention at least one of the flaps (11, 22) has a closure device (21) which reduces an outflow of the fluid that had previously flowed in during an inflow process. According to the invention, a closure-device (21) is furthermore arranged, wherein said closure device closes a region between the first flap (11) and the second flap (12) in the inflow position of the flaps (11, 12).

A check valve comprises a valve housing defining a pair of valve openings, a pair of flappers pivotably mounted for rotation relative to the housing between an open position in which they permit fluid flow through the respective valve openings and a closed position in which they prevent fluid flow through the valve openings, and a stop pin extending across the valve such that the flappers will contact the stop pin in their open positions. Each flapper comprises a primary flapper element and a secondary flapper element, each pivotally mounted to a hinge pin extending across the valve. The primary flapper element further comprises a flapper opening formed therethrough. The secondary flapper element is pivotally mounted to the hinge pin such that it may rotate relative to the primary flapper element for opening or closing the flapper opening.

A fluidizing butterfly valve. The fluidizing butterfly valve includes a valve body and a fluidizing valve disk or member configured to fluidize material located above the butterfly valve and/or material moving through the butterfly valve.

The present invention is directed to a self-aerating valve (1) comprising a valve body (2) with an aperture (3), and a valve flap (4) swivel-mounted to the valve body (2). The valve flap (4) is particularly configured to swivel between a closing position for closing the aperture (3), and an opening position for opening the aperture (3). Further, the self-aerating valve (1) comprises an air-supply port (5) connectable to an air-supply (12). The valve flap (4) is designed to release air supplied to the air-supply port (5) into the aperture (3) of the valve body (2) in the closing position. Preferably, the valve flap (4) is designed to release the air through its whole surface area (6), wherein the surface area (6) comprise a porous membrane (7) fluidly connected to the air-supply port (5). The self-aerating valve 1 may be used in an aerating system (11) of the present invention, which includes also an air-supply (12) fluidly connected to the air-supply port (5). The aerating system (11) may further comprise a drying unit (13) of the air-supply (12) adapted to dry and preferably also cool air supplied through the air-supply (12) to the air-supply port (5).

A check valve comprises a valve housing defining a pair of valve openings, a pair of flappers pivotably mounted for rotation relative to the housing between an open position in which they permit fluid flow through the respective valve openings and a closed position in which they prevent fluid flow through the valve openings, and a stop pin extending across the valve such that the flappers will contact the stop pin in their open positions. Each flapper comprises a primary flapper element and a secondary flapper element, each pivotally mounted to a hinge pin extending across the valve. The primary flapper element further comprises a flapper opening formed therethrough. The secondary flapper element is pivotally mounted to the hinge pin such that it may rotate relative to the primary flapper element for opening or closing the flapper opening.

A shut-off flap with a flap-shaped shut-off element, which is supported within a housing in such a way that it can swivel around a rotation axis and which contains a flap disk staggered relative to the rotation axis and lateral hubs to hold two drive shafts which are supported in such a way that they can rotate in the housing. In order to make possible an improvement of the throughflow and a reduction of the actuation torque, flow deflection elements are located on the two hubs.