An air injection apparatus is provided according to one embodiment of the present invention. The air injection apparatus includes a main body in which an air passage is formed, and an opening and closing part which is coupled to one end of the main body and in which an opening and closing protrusion having a predetermined length, protruding toward the air passage, and configured to open or close the air passage is formed on an inner surface thereof, wherein at least a part of the opening and closing protrusion may be inserted into the air passage to seal the air passage when the opening and closing part is moved in a first direction toward the main body.

A fill limit vent valve for a fuel system includes a housing assembly, an outlet port and a flow dam. The housing assembly has a main housing including a cylindrical body and an upper housing portion. The upper housing portion has a lower wall that defines an orifice and an outer cylindrical wall that defines an upper housing chamber. The outlet port is formed on the main housing and fluidly communicates fuel vapor out of the fill limit valve. The orifice is offset from a centerpoint of the lower wall in a direction away from the outlet port. The flow dam extends from the lower wall into the upper housing chamber and connects on opposite ends to the outer cylindrical wall. The flow dam and upper housing chamber cooperating to form a liquid trap that mitigates the possibility of liquid fuel from reaching the outlet port from the orifice.

The invention relates to a pressure maintaining gas cylinder valve. It consists of a pressure retaining device: The axis of the pressure retaining device and that of the valve element are in the same vertical plane; the pressure retaining device has a mounting base, a spring and a valve are located in the mounting base: the valve is in the valve element near the air outlet; the front section of the valve is near the air outlet, while the rear section of the valve is in the mounting base; the spring is between the valve and the mounting base. Because the invention has no eccentricity, the gas channel is smoother and the volume of the cylinder valve is greatly reduced. The mounting seat of the pressure retaining device not only provides support for the valve and spring, but also ensures that the stroke of the valve element is not interfered.

A safety release bleeder valve serving as a plug includes a barrel having an exterior surface and an interior throughbore surface for matingly receiving a plug having a top end with exterior threads and an interior socket for receiving a driver tool for moving the plug between an open venting state and a closed non-venting state.

A method for automatically opening or closing a gas barrel valve, includes: loading and aligning a gas barrel in a cabinet; separating an end cap from the gas barrel; screw-coupling a connector holder to a gas spray nozzle, from which the ends cap has been removed; winding a spring around a first shaft by enabling forward rotation of the first shaft while suppressing reverse rotation of the first shaft, which is installed in a valve handle holder so as to idle; opening a valve by enabling reverse rotation of a valve handle of the gas barrel while preventing forward rotation of the valve handle holder; and automatically closing the valve at the time of replacement of the gas barrel or when a gas leak is detected.

One embodiment is a device comprising a first and second section of a housing connected by a connection region that uses a plurality of connection elements, an inlet connected to the first or the second section, an outlet connected to the first or the second section where a gas can exit the housing, and a valve connected to the outlet, the valve capable of withstanding a first pressure in the housing.

A self-sealing safety valve (10) for a container of pressurised fluid (12) comprises a substantially solid body (14) and attachment means (24) for connecting to a dispensing valve. The self-sealing safety valve includes a substantially central bore (16) extending through both the attachment means and the solid body, and the bore connects an inlet (20) to an outlet (18). The bore comprises at least three parts each of a different diameter: a first part (16a) immediately adjacent the outlet has a first diameter; a second part (16b) located immediately adjacent the first part has a second diameter that is wider diameter than the first diameter; and a third (16c) part located immediately adjacent the second part has a third diameter that is wider than the second diameter. The second part of the bore houses a first biasing means (30). The third part of the bore houses a sealing ball (28) and a second biasing means (38), and the sealing ball is located between the first and second biasing means. The diameter of the sealing ball is greater than the first diameter but smaller than the second diameter and is capable of sealing the second part of the bore. Under normal flow conditions of fluid through the bore, the first biasing means is configured to bias the sealing ball away from the second part of the bore. Under conditions of high pressure fluid flow through the bore, the sealing ball is forced towards a junction (21) between the second and third parts of the bore, against the first biasing means, sealing the outlet.

A pressure compensation valve comprises a valve body, a valve sleeve fixedly mounted on the valve body, and a spool disposed in a valve hole of the valve body and capable of moving. The pressure compensation valve can change the pressure compensation characteristic, that is, the pressure compensation valve can change the difficult degree of the pressurized oil liquid flowing by changing an effective pressure acting surface of the pressure compensation valve The structure is simple, requires low cost, and increases the utilization rate of a product.

A fluid pressure regulating unit, comprises a fluid inlet port, a fluid outlet port, a valve comprising a movable valve part, wherein the movable part comprises at least one fluid pressure balancing means and wherein the at least one pressure balancing means comprises a tapered surface, and a main valve biasing means. The main valve biasing means biases said valve in the direction of an open position. An auxiliary valve biasing means is provided, biasing the valve in the direction of a closed position. Wherein essentially every surface part, being in fluid connection to the fluid inlet port and having a surface normal at least partially in parallel to the moving direction of the moving part of the valve, is balance by a balancing surface part.

A bag-in-keg container has a container body C, a flexible bag B within the container body, and a valve closure V attached to the container body. The valve closure includes a gas inlet port (11), a liquid dispensing port (12), and a spring-loaded valve member (6) to sealably close the gas inlet and liquid dispensing ports. An adapter (20) sealingly attached to the flexible bag B incorporates a bag PRV (26) to vent gas pressure from within the flexible bag. A container PRV (40) in the form of a flexible lip seal is operably associated with the valve member (6) to vent gas pressure from between the container body C and the flexible bag B. The lip seal is opened by a small positive pressure difference between inside and outside, but when the valve member (6) is opened to dispense liquid from the bag B the container PRV (40) is inoperative, allowing a relatively high internal gas pressure to be achieved when dispensing.