Abstract:
A nozzle ( 10 ) has a diaphragm valve ( 50 ) mounted at or near the downstream end of the spout ( 20 ). The diaphragm has an opening ( 56 ) responsive to fluid pressure in the spout, allowing fluid to pass with sufficiently high upstream pressure and preventing fluid, from passing with lower upstream pressure. The opening can have any suitable shape and size, but is preferably multi-branched, with a central point from which side openings radiate. The diaphragm is preferably place very close to the down-stream end of the spout to reduce dead space, and may advantageously be included in an installation frame ( 80 B).

Description:
FIELD OF THE INVENTION  
       [0001]     The field of the invention is fuel nozzles.  
       BACKGROUND OF THE INVENTION  
       [0002]     Gasoline and other fuel nozzles have a spout and a valve. The valve is typically located at the upstream end of the spout, leaving a distance within the spout in which the fluid can accumulate. This results in dripping, especially following dispensing of the fuel.  
         [0003]     Dripping is a significant problem. The drips cause hydrocarbons to leak into the atmosphere, which can in turn causes severe air and water pollution. In addition to being bad for the environment, hydrocarbons are also known carcinogens which harm people, eat through car paint, and accumulate in soil and concrete; all of which can lead to land deterioration and infrastructure erosion that can cost millions of dollars to clean up and restore. Dripping can also cause huge resource and economic waste. The Environmental Protection Agency (EPA) and Air Resource Board (ARB) are expected to pass new laws regulating the amount of gas drips that will be permitted.  
         [0004]     One approach to resolving dripping related problems is to locate the primary valve at the downstream end of the spout. Embodiments of this approach are described in U.S. Pat. No. 4,984,612 to de la Haye (January 1991), and U.S. Pat. No. 5,072,862 to Keller (December 1991). That approach, however, is not particularly practical. There is very little room at the downstream end of the spout, so that special valves need to be utilized. In addition to high cost and inherent unreliability, such valves are also subject to repeated physical insult during use.  
         [0005]     Another approach utilizes a secondary valve at the downstream end of the spout. One class of secondary valves locates a pop-out component that is at least partially external to the spout. Examples are U.S. Pat. No. 5,603,364 to Kerssies (February 1997), and U.S. Pat. No. 5,377,729 to Reep (January 1995). Unfortunately, such devices are also inherently problematic. The pop-out portion tends to get stuck in the gasoline tank or other container, and are in any event readily subjected to damage. The use of a part that exits the spout also produces a very real problem of vandalism.  
         [0006]     Another class of secondary valves are still located at the downstream end of the spout, but are wholly internal to the spout. These valves resolve some of the problems listed above, but produce yet other problems. A duckbill type of valve, depicted in U.S. Pat. No. 5,620,032 to Dame (April  1997 ), can be difficult to install and/or replace, and necessarily leaves additional space around the valve that can accumulate fuel. Thus, the duckbill type of valve reduces the amount of dripping, but cannot realistically be expected to eliminate dripping. An internal ball valve, such as that shown in U.S. Pat. No. 6,520,222 to Cbranchack et al. (February 2003), poses a a problem in the event that the balls falls into the tank, and may even create a dangerous situation in the event that the ball becomes caught in the opening of the fuel tank. In any event ball type valves located at the end of the spout will still accumulate a few drops of fuel after fueling, which doesn&#39;t truly solve the original problem. A pinch valve, as shown in U.S. Pat. No. 4,214,614 to Pyle (July 1980), likely has less room for fuel to accumulate, but has pressure problems. In order to open the pinch valve the pressure must be relatively high, which tends to disable the venturi automatic shutoff valve.  
         [0007]     Thus, none of the prior art valve systems are practical to substantially eliminate dripping, while still providing adequate flow, pressure, and safety characteristics. There is a still a need for an adequate solution to these problems, and preferably a solution that is readily adaptable to existing nozzles.  
       SUMMARY OF THE INVENTION  
       [0008]     The present invention is directed to a nozzle having a diaphragm valve mounted at or near the downstream end of the spout.  
         [0009]     In preferred embodiments the diaphragm is responsive to fluid pressure in the spout such that a portion of the diaphragm flexes as the pressure varies in the spout. It is especially desirable that the diaphragm flexes between a downstream position that opens the valve and an upstream position that closes the valve.  
         [0010]     The diaphragm provides a fluid passageway, which is advantageously in the form of a opening. The opening can have any suitable shape and size, but is preferably multi-branched, with a central point from which side openings radiate. Examples are X and Y shaped openings, as well as star shaped openings. Other contemplated fluid passageways include a central curved opening, such as a circular hole, which can cooperate with a fixed ball or other object to close the passageway.  
         [0011]     The diaphragm can be fabricated from any suitable material or materials, including for example a continuous piece of a polymer. Especially contemplated materials for this purpose are urethane, rubber, and silicone.  
         [0012]     The diaphragm is preferably placed very close to the downstream end of the spout, and most preferably has a circumference which is attached at the terminus of the spout. This provides substantially reduced dead space between the diaphragm and the end of the spout. The diaphragm may or may not extend substantially normally across the spout.  
         [0013]     At least a portion of the diaphragm must be flexible. Suitable diaphragms have sufficient flexibility such that during operation of the nozzle, a point of greatest travel of the diaphragm moves a relatively small amount, preferably less than 2 cm and more than 0.5 cm. Flexing of the diaphragm is preferably a passive function of changes in pressure of the fuel in the spout.  
         [0014]     The diaphragm can be inserted into the spout in any suitable manner, but preferably the diaphragm is packaged within an installation frame to facilitate installation.  
         [0015]     Various objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIG. 1A  is a vertical cross-section of a nozzle according to the inventive subject matter, in which the diaphragm is in a closed position.  
         [0017]      FIG. 1B  is a perspective view of the spout and diaphragm of  FIG. 1A , in which the diaphragm is in an open position.  
         [0018]      FIG. 2A  is a plan view of a diaphragm having a “Y” shaped opening, depicted in a closed position.  
         [0019]      FIG. 2B  is a plan view of a diaphragm having a “X” shaped opening, depicted in a closed position.  
         [0020]      FIG. 2C  is a plan view of a diaphragm having a star shaped opening, depicted in a closed position.  
         [0021]      FIG. 2D  is a plan view of a diaphragm having a donut shaped cutout, depicted in a closed position.  
         [0022]      FIG. 3  is a vertical cross-section of a downstream portion of a spout nozzle in which the diaphragm forms a seal against a fixed ball.  
         [0023]      FIG. 4  is a perspective view of the diaphragm of  FIG. 2B , depicted in an open position.  
         [0024]      FIG. 5A  is a perspective view of a diaphragm held within an installation frame, being inserted into the downstream end of a spout.  
         [0025]      FIG. 5B  is a vertical cross-section of a diaphragm in which the material is uniform in thickness.  
         [0026]      FIG. 6A  is a vertical cross-section of a diaphragm in which the material has been tapered with the middle being thinner.  
         [0027]      FIG. 6B  is a vertical cross-section of a diaphragm in which the material has been structurally reinforced with ribs.  
         [0028]      FIG. 7  is a vertical cross-section of a diaphragm in which the cutout opening has been reinforced with a thicker segment of material. 
     
    
     DETAILED DESCRIPTION  
       [0029]     In  FIG. 1 , a nozzle  10  generally comprises a spout  20 , a head  30 , and a handle  40 . The specific details of the spout  20 , head  30 , and handle  40  are not critical to the inventive design. Virtually any models can be employed. As is normally the case, the head has a primary valve  32  that is actuated by a trigger  42  through linkage  44 . Fuel or other fluid flows downstream in a path  12  through the hose  45 , into the head  30 , through the primary valve  32 , and out the spout  20 . The terminus  22  of spout  20  is depicted as dashed line  22 .  
         [0030]     The spout  20  is fitted with a diaphragm  50 , which as best visualized in  FIG. 1B , generally has a body  52 , a rim  54 , and an opening  56 . In  FIG. 1  the opening  56  would be in a closed position.  
         [0031]     In most installations it is important that the rim  54  be positioned downstream of the opening  24  to return fuel line  25  leading to the venturi valve (not shown) near the primary valve  32 . Otherwise the operation of the venturi valve could be compromised. Ideally, the rim  54  is located at or near the end (terminus)  22  of the spout to minimize downstream “dead space” within the spout, within which gasoline or other dispensed fluid could accumulate. Alternatively, the rim  54  could be located upstream of the end  22 , by any desired distance, such as up to a few mm, or even up to 1 cm, or more. The rim  54  can be held in place within the spout  20  by any suitable mechanism, including an installation frame (see  FIG. 5  below).  
         [0032]     In preferred embodiments the diaphragm  50  is responsive to fluid pressure in the spout  20  such that a portion of the diaphragm  50  flexes as the fuel pressure varies in the spout  20 . The amount and location of flexing within the diaphragm  50  is a design choice. In one class of embodiments the center of the diaphragm  50  flexes the most, and travels between about 0.25 cm and about 2 cm. More preferably the portion having the greatest travel moves between about 0.5 and 0.75 cm. It is also contemplated that the majority of the diaphragm  50  flexes relatively little, and most of the flexing is accomplished by the leaves  57  of the opening  56 B. (see  FIG. 4 ).  
         [0033]     The fluid pressure needed to open the diaphragm is a matter of design choice. Clearly the pressure must be greater than one atmosphere, but need not be very high. Thus, it is contemplated that opening pressures could be less than 1.1, 1.2, 1.3, 1.4, or 1.5 atmospheres. It is also contemplated that embodiments might be utilized in which much higher pressures are required to substantially open the diaphragm, such as up to 5 atmospheres or more.  
         [0034]     In most practical embodiments the opening  56  of diaphragm  50  is biased into a closed position, and flexes into an open position as a function of higher upstream pressure within the lumen of the spout  20 , and then reverts back to the closed position when the upstream pressure falls below a given value. It is possible to have the diaphragm extend essentially straight across the lumen of the spout  20 , but having the diaphragm bowed as shown in  FIG. 1  is thought to provide additional strength, durability, and consistency in operational parameters. It is also thought that having the body  52  of the diaphragm  50  biased into a bowed configuration assists in biasing the opening  56  into the closed position. This is especially true where there is residual upstream pressure, which actually assists in keeping the opening  56  closed.  
         [0035]     On the other hand, it is contemplated that the diaphragm  50  could be bowed outward, extending downstream, and possibly even out the end  22  of the spout. Thus, it is contemplated that the diaphragm  50  could have any resting position, from extending outwards (downstream), to extending substantially straight across the lumen of the shaft  20 , to extending inwards (upstream).  
         [0036]     The diaphragm  50  provides a fluid passageway, i.e., an opening  56  through which fuel can flow. The opening  56  can have any suitable shape and size, but is preferably multi-branched, with a central point are from which side openings radiate.  FIGS. 2A, 2B , and  2 C show “Y”, “X”, and star shaped openings, respectively. Other contemplated fluid passageways include a central or other curved opening, such as a circular hole, (See  FIG. 2D ), which can cooperate with a fixed ball  34  held in position by stabilizer  35  (see  FIG. 3 ), or other object (not shown) to close the passageway.  
         [0037]     A diaphragm can be inserted into a spout in any suitable manner. In  FIG. 5A  a diaphragm  50  is packaged within an installation frame  80 A to facilitate installation inside spout  20 . Such a frame  80 A can be fabricated or cast of any suitable material, but is preferably made of the material to the existing spout  20  to avoid expansion, cathodic dissolution due to redox reactions, and so forth. Preferred materials include nickel, aluminum, steel, and plastic. Installation frames are considered to be highly advantageous because they can be readily retrofitted into existing systems, and can readily adapt a standard diaphragm to substantially any nozzle size or shape. Installation frames can use any practical retaining apparatus or method, including, for example, springs, pressure fit, screw in, set screw, etc, all of which are depicted euphemistically by coupler  81 .  FIG. 5B  depicts an alternative embodiment in which an installation frame  80 B couples to the outside the spout  20 , rather than fitting entirely within the lumen of the spout  20 .  
         [0038]     Suitable diaphragms can be fabricated from any appropriate material or materials, including, for example, a continuous piece of a polymer. Especially contemplated materials for this purpose are urethane, rubber, and silicone.  FIG. 6A  depicts a diaphragm  50 E having rim  54  and a body  52 E having a substantially uniform thickness designated by arrows  67 - 67 .  FIG. 6B  depicts a diaphragm  50 F having rim  54  and a body  52 F having a relatively greater thickness  62 - 62  nearer the rim  54 , and a relatively lesser thickness  63 - 63  nearer the center of the diaphragm  50 F.  
         [0039]     Numerous other modifications are contemplated herein. For example, the edges of the leaves of the opening of a diaphragm can be reinforced with thicker material (not shown) than the remainder of the diaphragm, or with a different type of material. As another example, the edges of the leaves can overlap (not shown) or cooperate with one another in some other manner to facilitate closure of the opening, or to increase durability and strength. In yet another alternative embodiment,  FIG. 7  shows a diaphragm  50 G having opening  56 A and ribbing  72  disposed radially over each of the three leaves of opening  56 A.  
         [0040]     Thus, specific embodiments and applications of drip reducing nozzle and methods have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. For example, the apparatus and methods described herein can be used for dispensing of toxic chemicals, or for many purposes other than gasoline delivery. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps can be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.