Apparatus for Preventing Blockage of Vapor Recovery Hose by Liquid Fuel

The field of the present invention relates generally to vapor recovery hoses, and more specifically to such hoses including liquid removal apparatus for maintaining an unblocked vapor recovery path.

In fluid distribution systems, such as gasoline pumping systems for delivering gasoline to the fuel tank of a vehicle, environmental protection laws require that vapors emitted by the fluid being distributed be recovered. One such vapor recovery system includes a vapor recovery hose surrounding a product hose for delivering fuel to a nozzle, typically the nozzle of a gasoline pump. Vapors developed at the nozzle end are sucked by vacuum pressure from the nozzle back into the gasoline storage tank of the product distribution system via the vapor return path provided by the space between the product and vapor recovery hoses. At times liquid fuel may overflow from the nozzle into the vapor recovery path of the vapor recovery hose and collect at a low point in the vapor recovery hose causing partial or total blockage of the return path for the vapors. Even partial blockage of the vapor recovery path of the hose must be avoided in order to insure that the product distribution system meets the environmental protection codes imposed by local, state and federal governments.

Various embodiments of the present invention substantially prevent blockage of the vapor path of a vapor recovery hose by including wicking means along the length of the interior of the vapor recovery hose for both absorbing entrapped fluid therein, and for substantially increasing the area of evaporation for the entrapped liquid or fluid.

FIG. 1 is a sectional view taken along the longitudinal axis of a portion of a vapor recovery hose including a first embodiment of the invention;

FIG. 2 is a cross sectional view taken perpendicular to the longitudinal axis of the vapor recovery hose of FIG. 1;

FIG. 3 is a sectional view taken along the longitudinal axis of a portion of a vapor recovery hose including a second embodiment of the invention;

FIG. 4 is a cross sectional view taken perpendicular to the longitudinal axis of the vapor recovery hose of FIG. 3; and

FIG. 5 is a sectional view taken along the longitudinal axis of a vapor recovery hose including other embodiments of the invention.

In FIG. 1, a cutaway pictorial view of the interior of a vapor recovery hose 1 which is enclosing or carrying within in its interior space a product hose 3 is shown. The space between the inside diameter of a vapor recovery hose 1 and the outside diameter or wall of the product hose 3 provides a vapor return path 5, for vapors that may develop at the end of the product hose 3 connected to a nozzle (not shown) for transferring a liquid such as gasoline to a tank, for example. A first embodiment of the invention includes a wick material 7 surrounding the product hose 3. The wick material 7 can be provided as a coating on the outside diameter of product hose 3, or provided as a sleeve through which the product hose 3 is inserted, or can be provided as a ribbon or tape that is wrapped around the outside of the product hose 3, for example. FIG. 2 shows a transverse cross section of the combination of the vapor recovery hose 1, product hose 3, and wick material 7. Note that the product hose 3 may not be always concentric with the axis of the vapor recovery hose 1 in practical applications.

Operation of the embodiment of the invention of FIG. 1 will now be described. In transferring a product such as gasoline through the product hose 3 to a fuel tank, overflows of fuel at the entry way to the fuel tank may cause some liquid fuel to enter the vapor recovery path 5 and collect at a low point in the vapor recovery hose 1 as shown, by the liquid 9 accumulated at the low point of the vapor recovery hose depicted in this example. The accumulated liquid fuel 9 may cause partial blockage of the vapor recovery path 5, as previously indicated. The wick material 7 acts to absorb the accumulated liquid 9, and to spread the absorbed liquid along the entire length of the wick material 7 about the product hose 3, thereby substantially increasing the area for evaporation of the liquid fuel. In this matter, accumulation of the liquid 9 at low points in the vapor recovery hose is substantially prevented. The wick material 7 acts to substantially reduce blockage of the vapor recovery path 5 by liquid fuel that enters the vapor path 5. A typical material for the wick 7 is naturally leached cotton.

In FIG. 3, another embodiment of the invention is shown. In this embodiment wick material 11 is provided as a lining, or coating, for example, on the interior wall or inside diameter of the vapor recovery hose 1. The wick material 11 serves the same function as the wick material 7 shown in FIG. 1. A cross section of the embodiment of the invention of FIG. 3 is shown in FIG. 4. The first and second embodiments of the invention of FIGS. 1 and 3, can readily be combined to provide a vapor recovery system in which the vapor recovery hose 1 is lined with wick material 11, and the product delivery hose is coated or covered with a wick material 7, as shown in phanthom in FIG. 4. Note also in FIGS. 1 and 3, the directional arrows showing the typical directions of flow of fuel to a nozzle, and direction of flow of vapor return from the nozzle.

In FIG. 5, other embodiments of the invention are shown, wherein a tape or ribbon of wick material 13 is wound about the inside wall or diameter of the vapor recovery hose 1. Alternatively, a ribbon or tape or wick material 15 is wound about the product delivery hose 3 as shown in phanthom. Yet another alternative is to utilize ribbons or tapes of wick material 13 and 15 in combination as previously described.

Although particular embodiments of the invention have been shown and described, other embodiments and modifications of the invention will occur to those of ordinary skill in the art without departing from the true spirit and scope of the invention. For example, the various embodiments of the invention shown in FIGS. 1 through 5 may be used in many different combinations with one another. Also, the inventive use of the wick material is not limited to vapor recovery systems, and the invention is applicable for use for any system where liquid accumulation poses a problem. Examples of other systems where the present invention is useful are pressurized airlines, gas delivery pipelines, and so forth. Such systems may use single hoses for delivering a gas, for example, or twin hoses for delivering a liquid product in one hose and providing a vapor recovery hose with the other hose, and so forth. In addition, the wick material can be fabricated into the hose material during manufacture of the hose.