Abstract: A vent tube having a first branch and a second branch for use in a cryogenic container through which the interior of the container is communicated to the atmosphere. The cryogenic container is adapted to receive a fixed volume of cryogenic fluid at a uniform temperature and density. In a filling operation, the first branch of the vent tube contacts the cryogenic fluid and carries a portion of the fluid to the atmosphere to inform an operator that the capacity of the container has been reached. After the container is filled, the temperature in the stored cryogenic fluid rises. As the temperature changes, distinct stratified layers of fluid of different densities and temperatures can be measured in the container. The change in temperature causes the cryogenic fluid to expand and submerge the adjacent first branch of the vent tube.

Abstract: A cap for closing the filler neck of a vehicle fuel tank, the cap comprising a valve housing, a pressure-vacuum valve assembly disposed in the housing to vent the tank when the pressure in the filler neck drops below a predetermined subatmospheric level and when the pressure in the filler neck exceeds a first predetermined superatmospheric level, a roll-over valve for closing the pressure-vacuum valve assembly when the filler neck is tilted, and an excessive pressure valve for bypassing the pressure-vacuum valve when the pressure in the filler neck exceeds a second and greater predetermined superatmospheric level.

Abstract: A valve of a type used for preventing fuel line leaks which occur when automobiles or trucks roll over. The valve is used in conjunction with a vehicle fuel system, preferably in a vapor vent line which vents fuel vapors from the fuel tank, so that if the vehicle rolls over or tilts in one direction by more than a predetermined amount, the valve will close. A ball disposed in a conical recess within the valve body serves as a gravity actuator for a reciprocating valve member. A novel structure of a valve member of a particular configuration in combination with the novel configuration of the interior of the valve housing allows the valve member to be self-cleaning due to vibrations caused by vehicular travel; and yet, the valve provides a positive sealing function upon tipping or tilting thereof by a predetermined amount or more.

Abstract: A pressure-vacuum valved cap for a vehicle fuel tank having an upwardly extending filler neck formed with a peripherally extending, upwardly facing sealing lip or sealing surface concentric with the longitudinal axis of the neck, the cap comprising a cover, a valve body providing a centrally disposed passageway extending axially therethrough concentric with and in communication with the filler neck, the valve body being connected to the cover to extend downwardly into the filler neck, a seal provided between the valve body and the lip of the filler neck, and a pressure-vacuum valve assembly disposed in the passageway to normalize the pressure in the fuel tank. The improvement comprises a rubber-like insert having a concentric opening extending axially therethrough, an upper portion and a lower portion. The insert is held against the valve body so that the insert upper portion engages and seals against the valve body about the vent opening which is in communication with the passageway.

Abstract: This invention relates to a vent valve having an elongated housing. The housing has an inlet port positioned below an outlet port when the housing is in an upright position. A passage connects the inlet and outlet parts. The passage construction provides free passage of gaseous fluid but restricts momentary liquid flow or splash when the housing is in an upright position. A ball valve in the passage restricts liquid flow when the housing is tilted more than 90.degree. from its upright position.

Abstract: Disclosed is an improved tank vent. The vent prevents liquid loss if the tank is inverted and prevents contaminants from entering the tank. The vent includes an elongated housing forming a tubular chamber communicating with the interior of the tank. Disposed within the chamber is an annular valve seat. Disposed within the chamber adjacent the valve seat is a free sliding elongated buoyant valve member. The buoyant valve member has a protruding valve surface disposed on the end of the buoyant member adjacent the valve seat. The surface area of the valve surface is significantly less than the surface area of the end of the buoyant member upon which the valve surface is disposed. The valve surface is configured to sealably engage the valve seat for movement into and out of contact with the seat as the buoyant member moves within the chamber.

Abstract: A gas vent tube for removing gas from a container while minimizing loss of iquids. The vent is mounted in a cylindrical container on a 360.degree. rotating joint and has a buoyant material attached to always maintain the vent in an upright position. The pickup tube also has a buoyancy closure valve to prevent the loss of liquid when the end of the pickup tube is not in a gas, and may be provided with a check valve when the container is submerged in a second liquid to prevent the intrusion of the second liquid into the container.

Abstract: A pressure-vacuum cap for a chamber such as an automobile gas tank having a normally upwardly extending filler neck formed with a peripherally and radially extending, upwardly facing sealing surface concentric with the longitudinal axis of the neck, the cap comprising a cover, a concentric housing extending downwardly from the cover into the filler neck and a gasket or gaskets providing a seal between the housing and the sealing surface, the housing providing a valve body having a centrally disposed, concentric passageway extending axially therethrough and in communication with the chamber. A pressure-vacuum valve arrangement is disposed in that passageway for normalizing the pressure in the chamber, venting the chamber to atmosphere when the pressure in the chamber exceeds a predetermined superatmospheric level and when the pressure in the chamber drops below a predetermined subatmospheric level. The valve body also provides, in addition to the pressure-vacuum valve arrangement, a roll-over valve feature.