A tank refilling system is configured to keep liquid in a destination tank close to a predetermined destination tank fill line. The tank refilling system has a source tank connected to a destination tank with a flow through secondary process therebetween. Liquid flows between the tanks by gravity fed drainage. A single liquid supply channel to transfer pressurized supply liquid is comprised of a plurality of piping segments and one or more valves, all connected in series. A source tank mounted valve is configured to permit liquid to flow until the height of liquid level in the source tank reaches a predetermined level. A destination tank mounted valve is configured to permit liquid to flow until the height of liquid level in the destination tank reaches a predetermined level. The apparatus of the invention also prevents tank overflow for both the source tank and the destination tank.

A backflow valve assembly for preventing gas and backup waste from escaping a floor drain includes a tube that is configured to fluidically couple to a drain line. A pipe is coupled to and axially positioned in the tube. The pipe has upper and lower ends that are closed. At least one gasket is coupled to an inner surface of the pipe and defines upper and lower chambers. Penetrations are positioned through the pipe to allow flow of gasses and liquids into the pipe. First and second balls, which are less dense than water, are positioned in the upper and lower chambers, respectively. The first ball prevents escape of the gasses from the tube. The first ball floats to open the gasket to permit the flow of the liquids to the drain line. The second ball floats to close the gasket to prevent escape of waste from the tube.

A valve assembly may be used with a container for holding a fluid including a liquid and a gas. The valve assembly may have a chamber, inlet, and outlet. The chamber may provide an exhaust route for fluid from the container to the outlet. A check valve including a sealing member with a through hole may move between an open and closed position. In the open position, check valve may provide a main flow route for fluid leaving the internal chamber. The through hole may provide a limited return flow route for gas returning to the internal chamber when the check valve is closed. The valve assembly may include a breather check valve movable between a closed and open position in which it provides fluid communication between the exhaust route and externally of the housing. A filter may communicate with the breather check valve.

A fuel tank valve device includes a housing in which a partition wall defines a lower valve chamber and an upper ventilation chamber, and a first opening and a second opening are provided to establish a communication between the lower valve chamber and the upper ventilation chamber, a first float valve that is accommodated in a first valve chamber of the lower valve chamber so as to rise and fall and that closes the first opening when a fuel level in a fuel tank nearly reaches a set full fuel level, and a second float valve that is accommodated in a second valve chamber of the lower valve chamber so as to rise and fall and that closes the second opening when the fuel level in the fuel tank rises abnormally.

There is provided a liquid level control device (20) for location in a vessel to control the liquid level in the vessel. The liquid level control device (20) comprises: a first chamber (22) including: an opening (26) to allow movement of liquid between the first chamber (22) and the vessel; a vent (28) to allow egress of air from the first chamber (22); and an inlet (30) connectable to a liquid source (34); a first flow controller including a first float (36) arranged in the first chamber (22) such that the flow of liquid into the first chamber (22) raises the first float (36) and displaces air in the first chamber (22) via the vent (28), the first flow controller including a first closure member (40) movable to selectively close and open the inlet (30), the first float (36) further arranged in the first chamber (22) such that, in use, when the first float (36) is at a first position when the liquid level in the first chamber (22) is at or below a first predetermined level, the first float (36) positions the first closure member (40) to open the inlet (30) to allow liquid into the first chamber (22) via the inlet (30), and when the first float (36) is at a second position when the liquid level in the first chamber (22) is at or above a second predetermined level, the first float (36) positions the first closure member (40) to close the inlet (30) to block liquid from entering into the first chamber (22) via the inlet (30); and a second flow controller including a second float (42) and further including a second closure member (46) movable to selectively close and open the vent (28), the second float (42) arranged such that, in use, when the second float (42) is in a first position, the second float (42) positions the second closure member (46) to close the vent (28) to block air from flowing from the first chamber (22) via the vent (28) to escape to atmosphere, and when the second float (42) is in a second position, the second float (42) positions the second closure member (46) to open the vent (28) to allow air to flow from the first chamber (22) via the vent (28) to escape to atmosphere, wherein the first and second floats (42) are arranged such that, in use, when the first float (36) is in its second position and the second float (42) is in its first position, air is trapped in the first chamber

An opening/closing device according to the present invention includes a gate, a fall prevention unit, a support release unit, a first float, a floating prevention unit, a second float, and a floating prevention release unit. The gate receives a flow of fluid, and is able to fall down toward a downstream direction of the flow. The fall prevention unit supports the gate, thereby preventing the gate from falling down. The support release unit releases the support for the gate by the fall prevention unit. The first float is arranged on an upstream side of the gate, is arranged on one of the left side and the right side of the gate viewed from upstream, and is less in the specific gravity than the fluid. The floating prevention unit prevents the first float from floating.

A valve assembly, that may be used on and/or retrofitted to various float valves, comprising: a relief valve configured to be movable between a closed position and an open position allowing pressure from a container to be relieved through at least one relief hole; a breather float configured to be movable between an open position allowing gas to pass through at least one breather hole and a closed position that substantially prevents liquid from passing through the at least one breather hole; and at least one of: a check valve that is movable between a closed position and an open position allowing gas to be relieved from the container when the container is being filled with liquid; and a breather check valve that is movable between a closed position and an open position allowing filter gas to enter the container when liquid is being removed from the container.

A valve device for a fuel tank has a housing having a valve chamber which is provided below a partition wall and a ventilation chamber which is provided above the partition wall; a recess having a first opening formed in the bottom section thereof and defining a part of the ventilation chamber; and a fuel vapor discharge opening formed in the inner periphery of the recess. The partition wall has a shelf-like wall section extending from the peripheral edge of a second opening and reaching the inner periphery of the recess. The shelf-like wall section has formed therein a first groove section extending from the second opening side and connecting to the recess. A ceiling wall is disposed above the shelf-like wall section with a gap therebetween.

An overfill prevention valve for use with a tank includes a valve element disposed in a fluid fill path and a float assembly including an actuator and a repositionable float. The float is selectively fixed relative to and moveable relative to the actuator to adjust a target fill level. The float is buoyantly supported by the fluid such that the float and the actuator are shiftable in correspondence with an actual fill level. The actuator is coupled with the valve element such that the valve element shifts to a closed position when the actual fill level nears a target fill level. The float includes discrete buoyant components that are shiftable away from each other and from the actuator to facilitate shifting of the float relative to the actuator and that are securable relative to each other and relative to the actuator to facilitate operation of the float assembly.

An overfill prevention valve for use with a tank includes a valve element disposed in a fluid fill path and a float assembly including an actuator and a repositionable float. The float is selectively fixed relative to and moveable relative to the actuator to adjust a target fill level. The float is buoyantly supported by the fluid such that the float and the actuator are shiftable in correspondence with an actual fill level. The actuator is coupled with the valve element such that the valve element shifts to a closed position when the actual fill level nears a target fill level. The float includes discrete buoyant components that are shiftable away from each other and from the actuator to facilitate shifting of the float relative to the actuator and that are securable relative to each other and relative to the actuator to facilitate operation of the float assembly.