Abstract:
A choke for reducing spray of fuel exiting a fuel dispensing system nozzle spout having an annular frame positioned within the spout adjacent the output opening. The choke has a concentric hub connected to the frame by three, relatively narrow struts positioned equidistant around the hub. The hub has a solid, cylindrical fore section tubular aft section. A duct extends from the tubular aft section, through one strut and the frame, to the sensing port. Fuel flowing through the spout toward the output opening, it is slowed and divided into three streams by the choke, flows along the hub fore section and converges, compressed and linearly aligned, at the output opening of the spout to reduce spraying of fuel at the output opening of the spout and avoid unwanted shut-off.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     None 
     BACKGROUND OF THE INVENTION 
     The invention relates generally to fuel dispensing nozzles and, more specifically, to an improved apparatus for straightening the flow of fuel out of tip of the nozzle spout. 
     In general, a fuel dispensing system, such as a system for dispensing liquid fuel such as gasoline at a gas or service station, includes a storage tank, a pump, a delivery hose connected at one end to the pump and a dispensing nozzle at the other end of the hose. The dispensing nozzle generally has a handle structure, an actuator for opening the nozzle and permitting flow, and an elongated spout designed to fit into a vehicle fuel tank fill neck. 
     The pattern of the fuel as it exits the spout can affect how well the nozzle can fill up a vehicle. If the pattern fans out, then there are problems filling up the vehicle tank. In general, when the vehicle tank is filled up the air/vapors in the empty tank have to exit the tank through the same conduit, or fill neck, that the fuel travels into the tank. This conduit is generally larger than the spout O.D. If the spray pattern of fuel expands out to fill the I.D of the conduit, the exiting air/vapors have to exit back through the fuel flow and tend to blow some of the fuel back onto the nozzle sensing port which is operatively connected to a shut-off, as known in the art. This blowback will cause the nozzle to shut off. This requires the customer to restart the nozzle, which is inconvenient for the customer. If the pattern of fuel does not expand, then there is room in the conduit for the air/vapors to escape without affecting the fuel flow or prematurely shutting off the nozzle. 
     With nozzles of known designs, there can be a fitting on the bottom inside of the spout. This fitting interrupts the flow of fuel and creates the spray pattern. In the past, others have attempted to control the flow by employing elongated X-shaped or V-shaped deflectors within the nozzle adjacent the discharge opening. The devices were made of metal, could deteriorate or corrode, and sometimes interfered with the sensing port that is connected to an automatic shut-off to halt fuel flow when the vehicle fuel tank is full. 
     Some nozzles avoid this fitting by adding a separate coaxial flow chamber for the fuel to flow out of. These types of nozzles have a good “non-spray” flow pattern, but by causing the fuel to flow through a smaller coaxial tube, the exit velocity is much greater than with a conventional spray spout. This increased exit velocity can cause problems with fill necks that are not straight. This jet of fuel will hit a bend in the fill neck and break up spraying back on the sensing port, resulting in the same shut of condition that is caused by an expanding spray pattern. 
     It would be helpful, therefore, to have an apparatus in the spout that controls the flow of fuel out of the nozzle, resulting in a tight, low velocity stream. 
     SUMMARY OF THE INVENTION 
     It is among the various aspects and objects of the present invention to provide an apparatus for positioning within the discharge nozzle of the fuel-dispensing nozzle to provide for a tightened and low velocity stream of fuel from the nozzle to control undesirable spraying of fuel. 
     Another aspect of the invention is to provide for such an apparatus that provides tightened and low velocity stream of fuel from the nozzle to control undesirable shut off of fuel flow. 
     One aspect of the invention is directed toward a choke positionable within the discharge spout of the fuel-dispensing nozzle to constrict and align the flow of fuel and slow the velocity of the fuel stream. 
     A preferred embodiment of the choke of the present invention includes an annular frame having a circumference slightly less than the circumference of the bore of the nozzle spout so that the body fits snugly within the spout adjacent the output opening of the spout. The choke has a concentric hub connected to the frame by three, relatively narrow struts positioned equidistant around the hub. The hub has a generally solid, cylindrical fore section extending toward the spout opening and an open ended, tubular aft section. A duct extends from the tubular aft section, through one strut and the frame, to the sensing port which is operatively connected to a shut-off. 
     When fuel flows through the spout toward the output opening, it is slowed and divided into three streams at the choke. The streams of fuel flow along the fore section of the hub and converge, somewhat compressed and generally aligned, near the output opening of the spout. The compressed, linearly align fuel stream then exits the output opening with less spraying or splashing. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side elevational view of a conventional fuel dispensing system dispensing nozzle; 
     FIG. 2 is a rear perspective view of the fuel flow straightener of the present invention; 
     FIG. 3 is a front elevational view thereof; 
     FIG. 4 is a cross-sectional view taken along line  4 — 4  of FIG. 3; 
     FIG. 5 is a perspective view of the flow straightener of the present invention installed in the spout of a fuel dispensing nozzle; 
     FIG. 6 is a front elevational view of an alternative embodiment of the fuel flow straightener of the present invention installed in a spout; and 
     FIG. 7 is a cross-sectional view thereof taken along line  7 — 7  of FIG.  6 . 
    
    
     Corresponding reference numerals indicated corresponding elements throughout the various drawings. 
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The novel fuel flow straightener of the present invention is generally intended to be installed in the spout of a fuel dispensing system dispensing nozzle indicated generally as N in FIG.  1 . Nozzle N is connected to a dispensing pump (not shown) by hose H and includes an actuator A to start and stop flow through the nozzle and a dispensing spout S. Spout S is configured and sized to allow introduction into the fill tube of a vehicle or into a storage container, such as a gas can. The spout has a discharge orifice O at one end and the opposite end is in fluid communication with the fluid flowing from the pump through the nozzle. Each nozzle may include a sensing port opening (e.g. opening V in FIG. 5) operatively connected to a conventional shut-off mechanism that stops the flow of fuel when the receptacle is full, as known in art. In any event, nozzle N is intended to represent any type or design of a fuel dispensing nozzle with which the flow straightener of the present invention may be used. 
     The novel fuel flow straightener, which can be referred to as a choke, is indicated generally by reference numeral  10  in FIGS. 2-4. Choke  10  has an annular frame  12 , a concentric hub  14  and three struts  16 ,  18  and  20 . Frame  12  has a diameter which is slightly less than the inside diameter of the spout S in which it will be installed. Frame  12  is depicted as being annular in the illustrated environment because the cross-section of spout S is annular. It is understood that frame  12  could have any other configuration corresponding to the cross-section of the spout or discharge apparatus in which it is installed, including ovoid, rectangular or the like. 
     As shown in FIG. 4, hub  14  has a relatively elongated cylindrical configuration which arbitrarily will be described has comprising two sections, a solid fore section  22  and an open-ended, tubular aft section  24  having a bore  26  formed therein. Fore section  22  is generally cylindrical in configuration and has a conical tip  28 . 
     Struts  16 ,  18  and  20  are position an equidistance about the hub at approximately 120° angles and connect hub  14  to frame  12  in a manner that adds rigidity and strength to the apparatus. Struts  16  and  18  are identical in structure, being, in the exemplary embodiment, solid rectangular members having front and rear surfaces  30 ,  32  and opposed side surfaces  34 ,  36 , all of substantially the same length. Side surfaces  34  and  36  are wider than the front and rear surfaces  30 ,  32 , respectively, having the same width as frame  12 . As will be appreciated, the struts are relatively narrow so that they can slow and divide the flow but do not cause excessive resistance to, or turbulence in the fuel 
     As best seen in FIG. 4, spoke  20  has a different configuration, having front and rear walls  38 ,  40  and side walls  42 ,  44 . The four walls define an inner cavity  46  that is in fluid communication with bore  26 . Spoke  20  includes a hollow contiguous annular extension  48  that bisects, and is located on the outer surface of, frame  12  forming an open duct through the frame at that point. As will be appreciated from viewing FIG. 4, there is a continuous open flow pathway from extension  48 , through chamber  46  and bore  26 . Extension  48  is dimensioned so that it will fit into a sensing port V, when the choke is installed in a nozzle spout and allow the automatic shut-off to function properly in the presence of fuel flow past the choke. If the choke  20  is intended to be used in a discharge apparatus that does not have a sensing port opening, strut  20  can be constructed the same as struts  16  and  18 . 
     As explained above, the circumference of frame  12  is such that the choke fits snugly inside the spout near the output opening of the spout, with extension  48  positioned inside the opening and secured, either by a tight friction or with other acceptable means such as an adhesive or the like. The exemplary embodiment of choke  10  is constructed or molded from a substantially rigid yet resilient chemical resistant material, for example a resinous plastic material such as Delrin® (Dupont, Wilmington, Del.). However, it will be understood that the choke of the present invention can be constructed from any acceptable material such as metal, plastic, resin, or any other suitable material now known or unknown, in one piece or an assembly of pieces, without departing from the  15  scope of the appended claims. 
     The choke  10  is employed to reduce spraying as a fluid exists the discharge orifice of a fluid dispensing apparatus, such as a spout. The term spraying is intended to mean the common definition of spraying, including, but not limited to, any undesired or random discharge of some of the fluid. In the illustrated application, the fuel flows as a stream through its fluid flow path and the spout and eventually through choke  10 . Extension  48  allows the automatic shut-off to function, if one is present. 
     The flowing fuel stream is slightly slowed and divided into three streams at the choke by the struts, with the relatively wider side walls of the strut forming stream guides. The three streams flow separately along the side walls of the struts and the fore section of the hub and converge at a point beyond the pointed tip of the hub, where they form a more compressed or constrained stream comprised of three linearly aligned streams. This convergence occurs very near the output opening O of the spout. Consequently, because the stream of fuel is slightly slowed and relatively linear and compressed or constrained, there is less spraying of the fuel as it exists the spout. 
     FIGS. 5 through 7 illustrate another exemplary embodiment of the flow straightener of the present invention, indicated generally in the drawings as numeral  50 . Referring to FIGS. 6 and 7, straightener or choke  50  includes a generally cylindrical frame  52  with a concentric hub  54  secured to the body by three struts  56 ,  57  and  58  extending at 120° from the hub. It will be noted that frame  52  is longer than annular frame  12  of choke  10 . Hub  54  is positioned near the posterior end of the frame  52  and has an anterior section defined by an anterior frame wall  62 . Frame wall  62  has circumferential groove  64  formed in the outer surface. The inner surface  66  of the anterior frame wall is tapered to define a bore  68  that is tapered in from rear to front. 
     Hub  54  has a solid cylindrical fore section  70  with a rounded tip  71  and a concentric, open-ended tubular aft section  72  with inner bore  74 . Described aft to fore, bore  74  has a first section  76 , a second tapered second section  78 , and a third concentric section  80 . 
     Struts  56  and  57  are relatively narrow rectangular members having relatively longer sidewalls. The struts extend from the hub at approximately 120° angles. Strut  58 , however, is substantially wider than the other struts, as seen in FIG.  6 . As shown in FIGS. 5 and 7, there is an annular extension  82  on the top of strut  58  which is configured to fit into the sensing port V. There is a duct  83  connecting the automatic shut-off sensing port to bore  74 . 
     Choke  50  can be constructed or molded from the materials described above. The circumference of choke  50  is such that it fits snugly in the spout. The anterior frame wall  62  can be slightly compressed at circumferential groove  64  when the choke is inserted in the spout. Extension  82  fits into the sensing port and the resilient anterior frame wall  62  then is biased against the inner wall of the spout. The choke can be maintained in position in this manner or further secured in place with a chemically compatible adhesive or the like. 
     In use, the fuel flows as a stream through the spout and eventually through choke  50 . Extension  82  allows the nozzle automatic shut-off to function. The flowing fuel stream is slightly slowed and divided into three streams at the choke by the struts. The three streams flow substantially separately along strut walls and the fore section of the hub and converge at a point beyond the tip of the hub, very near the output orifice of the spout, where they form a more compressed stream comprised of three linearly aligned streams. In choke  50 , the stream is further constrained at the outflow opening by the tapered bore  68 . Consequently, because the fuel stream is relatively slowed, linear and compressed or constrained, there is substantially less spraying of the fuel as it exists the spout output orifice. Blow back is eliminated and unwanted shut-off is avoided. 
     Although a major application of the flow straightener of the present invention is its use in a fuel dispensing nozzle, it will be understood that the invention can be employed in any fluid discharge or dispensing apparatus, other than fuel, without departing from the scope of the invention. For example, the straightener can be employed in a liquid dispensing spout in another environment, such as a water hose, beverage dispenser, or any other fluid flow or dispensing system without departing from the scope of the appended claims. Therefore, the foregoing description and accompanying drawings are intended to be illustrative of the best mode of working the invention and described the invention in one particular application for brevity and clarity and are not intended to be construed in a limiting sense.