Fuel dispensing nozzle with built-in flow regulator

A fuel dispensing nozzle for refueling vehicles is disclosed. The nozzle provides a poppet valve for manually controlling the flow rate through the nozzle and an automatic flow control regulator for limiting the maximum flow rate through the nozzle to a predetermined maximum flow rate. The illustrated embodiment provides the automatic flow regulator in an existing passage within the nozzle body downstream from the poppet valve. Therefore, the regulator can be retrofitted into existing nozzles without separate fasteners or the like. The regulator includes a polymeric sleeve having lateral ports and a piston slidable in the sleeve providing an orifice around the operating rod of the poppet valve. A spring normally maintains the piston in its full open position. When flow rates approach the maximum desired predetermined flow rate, a pressure drop occurs through the orifice, producing a force overcoming the spring and causing the piston to move down and partially cover the ports in the sleeve. This results in throttling of the flow through the nozzle and limits the flow to rates below the predetermined maximum desired flow rate.

BACKGROUND OF THE INVENTION 
This invention relates generally to fuel dispensing nozzles, and more 
particularly to a novel and improved fuel dispensing nozzle incorporating 
an automatic flow regulator operable to limit flow rates through the 
nozzle to a predetermined maximum flow rate. 
Prior Art 
Federal government agencies have concluded that fuel spills can be 
significantly reduced and, in most instances, virtually eliminated if the 
maximum fuel flow rate in the refueling of noncommercial vehicles is 
appropriately limited. 
If the fuel is dispensed at a rate greater than the rate the vapor can be 
displaced from the vehicle fuel system, back pressure builds up, causing 
premature shutoff of the fuel nozzle and the possibility of fuel spitback. 
Further, the capacity of the on-board vapor recovery system of the vehicle 
is exceeded if the fueling rates are excessive. 
Older and smaller service stations tend to use a suction pump which is 
located inside the individual dispenser. These suction pump dispensers 
normally operate at relatively low flow rates. However, newer, higher 
volume facilities use submersible turbine pumps which are located away 
from the dispenser and are either on or in the underground storage tank. 
They serve all of the dispensers and nozzles drawing fuel from the 
associated tank. Thus, the actual flow rate varies, depending upon the 
number of nozzles being operated from one pump. The submersible pumps are 
of higher horsepower and are capable, in many instances, of dispensing 
fuel at excessive rates, tending to cause spills and spitback. 
In order to minimize pollution resulting from fueling spills and the like, 
it is desirable to provide a fueling system in which the fueling rate from 
a given nozzle is limited to a standardized maximum flow rate, and for 
vehicle producers to structure the vehicle fuel system and the on-board 
vapor recovery system to have the capacity to properly receive the fuel at 
such maximum rate. One suggested maximum flow rate is ten gallons per 
minute. 
It is known to provide a separate automatic flow regulator in the flow 
conduit ahead of a nozzle to control the maximum fuel flow rate through 
the associated nozzle. However, such regulators tend to be relatively 
expensive and require additional connections which are a source of 
possible leaks. Further such separate regulators are often removed from 
the system by the station operators. 
SUMMARY OF THE INVENTION 
The present invention provides a novel and improved flow dispensing nozzle 
incorporating within the nozzle itself an automatic flow regulator which 
operates to prevent flow rates in excess of predetermined maximum values. 
Such flow regulators are economical and can be retrofitted into many 
existing nozzles, as well as being supplied in new nozzles. The 
illustrated embodiment requires only three significant parts: two molded 
polymeric parts and a single compression spring. Further, the regulator 
does not require any special structure within the basic nozzle 
construction. 
In the illustrated embodiment, the nozzle provides a manually operable 
poppet valve through which the fuel flows when the poppet valve is opened 
by the user. If the poppet valve is opened a small amount, the flow rate 
of fuel through the nozzle is determined by the degree of opening of the 
poppet valve. 
Positioned immediately downstream from the poppet valve is an automatic 
flow regulator providing a sleeve having lateral openings or ports 
therein. Positioned within the sleeve is a piston biased in one direction 
by a compression spring. The operating rod for the poppet valve extends 
through the sleeve and the piston. The low flow control actuator may also 
extend through the piston. 
The piston and the poppet valve operating rod cooperate to define an 
annular orifice therebetween. When the pressure, and thus flow rates, are 
low, the spring maintains the piston in the position in which it does not 
cover the lateral ports in the sleeve and the flow through the nozzle is 
established by the poppet valve. However, when the poppet valve is moved 
to or approaches a fully open position or the pressure is raised and would 
allow excessive flow rates of fuel, the pressure differential increases 
across the orifice in the piston and the piston is moved by such pressure 
differential resultant force against the action of the spring. The piston 
moves to a position in which the skirt of the piston partially covers the 
lateral side ports in the sleeve to reduce the flow area and thus limit 
the fuel flow rate. 
The size of the orifice and the force exerted by the spring determine the 
flow rate which will be permitted by the regulator. If, for example, the 
desired maximum fuel flow rate is ten gallons per minute, the regulator is 
calibrated to limit the flow rate to values not exceeding ten gallons per 
minute. 
With the present invention, a simple, low-cost regulator is incorporated 
into each nozzle. Such regulator automatically limits the flow rate 
through the nozzle to a predetermined value and minimizes or eliminates 
fuel spills. The regulator is positioned within a previously existing 
nozzle passage, and therefore does not require any special nozzle 
structure. In fact, the illustrated regulator can be retrofitted in many 
existing nozzles. 
Because the regulator is located within a previously existing nozzle 
passage, additional external connections are not required. Therefore, the 
provision of the regulator does not increase the number of external 
connections and does not increase the number of possible leakage paths. 
These and other aspects of this invention are illustrated in the 
accompanying drawings, and are more fully described in the following 
specification.

DETAILED DESCRIPTION OF THE DRAWINGS 
FIG. 1 schematically illustrates an overall fueling system of the type to 
which the present invention is particularly suited. This system provides a 
fuel tank 10 for supplying fuel to two or more dispensers 11. A pump 12 is 
provided to pump the fuel out of the tank 10 and to supply fuel under 
pressure to each of the dispensers 11. Each dispenser is provided with a 
fuel dispensing nozzle 13 connected to the associated dispenser by a 
flexible hose 14. 
Since the single pump 12 supplies fuel to more than one dispensing system, 
its capacity is normally selected so that a flow rate is available to 
adequately supply fuel under pressure simultaneously to all of the 
associated nozzles. Consequently, the capacity of the pump 12 is often 
sufficiently great to deliver an excessive amount of fuel to a given 
nozzle when only one nozzle is being supplied by the pump. 
In accordance with the present invention, each of the nozzles 13 is 
provided with an automatic flow regulator connected in series with the 
manually operable valve of the nozzle so that the desired maximum flow 
rate will not be exceeded by any given nozzle under any operating 
conditions. 
Therefore, if only one vehicle 16 is being fueled at a given time, the 
maximum flow rate is the maximum desired flow rate for the system. On the 
other hand, even when two or more vehicles are being fueled at a given 
time, the flow rate to each nozzle can approach the maximum flow rate 
mentioned above. 
FIG. 2 schematically illustrates a typical fuel nozzle incorporating the 
present invention. Such nozzle includes a body 21 having an inlet 22 
connected to the supply hose 14 and through which fuel enters the nozzle. 
Downstream from the inlet is a manually controllable poppet valve 23 
operated by the user to control the fueling of a vehicle. 
Downstream from the poppet valve 23 is an automatic flow regulator 24 
through which the fuel must pass after passing through the poppet valve 
23. Downstream from the flow regulator 24 is a typical automatic shutoff 
25 (not specifically illustrated) for automatically shutting off the 
nozzle by closing the poppet valve 23 when fuel is sensed at the outlet or 
delivery end 26 of the nozzle. 
The automatic shutoff apparatus of the nozzle usually functions to release 
a pivot for the user-operated handle 27 to cause the poppet valve 23 to 
automatically close whenever fuel reaches the outlet end 26 of the nozzle. 
Those skilled in the art are familiar with the structure and operation of 
automatic shutoff systems which are commonly used in the industry. The 
particular shutoff system forms no part of this invention except to the 
extent it is defined in the accompanying claims. 
Reference should now be made to FIGS. 3 through 6, which illustrate the 
structural detail and mode of operation of the combination poppet valve 
and automatic flow regulator in accordance with the present invention. 
The body 21 provides an inlet passage 31 through which the fuel from the 
inlet 22 (illustrated in FIG. 2) flows to the poppet valve 23. Located in 
the passage 31 is an annular valve seat 32 extending around a lateral 
passage 33 which is cylindrical and extends between the passage 31 and a 
downstream passage 34. At the inner end of the lateral passage 33 is a 
lateral wall 33a substantially perpendicular to and aligned with the 
lateral passage 33. All of these passages 31, 33, and 34 are defined by 
integral walls 35 of the body, which is preferably a cast or molded 
metallic member. 
Positioned within the lateral passage 33 is a poppet valve assembly 
including a poppet head 36, an elastomeric seal ring 37, and a cap member 
38. The poppet head 36 extends down into the passage 33 and is laterally 
positioned thereby while being axially movable therealong. 
Coaxial with the lateral passage 33 is a threaded opening 41 in the wall 35 
of the body 21. A cap 42 is threaded into the opening 41 and provides a 
fluidtight joint therewith by means of an O-ring type seal 43. Extending 
between the cap 42 and the cap member 38 of the poppet assembly is a 
compression spring 44. This spring normally maintains the poppet valve 23 
closed (as illustrated in FIG. 3) in a position in which the elastomeric 
seal ring 37 engages the valve seat 32 to prevent flow from the passage 31 
into the lateral passage 33. However, when the handle 27 (illustrated in 
FIG. 2) is operated, it raises an operating rod 46 which extends through 
the lateral wall 33a into the poppet head 36 at its upper end and causes 
the poppet head to be raised with respect to the valve seat 32 against the 
action of the spring 44. This, in turn, lifts the elastic seal ring 37 
away from the valve seat and opens the poppet valve, allowing fuel flow 
from the passage 31 along the passage 33 into the passage 34. 
The lower end of the operating rod 46 extends through a seal assembly 47 to 
prevent leakage along the rod of the nozzle. 
The structure thus far described is conventional and has been marketed by 
the assignee of the present invention for a considerable period of time, 
and constitutes prior art with respect to the present invention. However, 
in such nozzles, there is no automatic flow regulator 24 and the maximum 
flow rate through the nozzle is solely a function of the pressure of the 
fuel being supplied to the nozzle and the general configuration and size 
of the various components of the nozzle itself. In many installations, 
such nozzles function, when the poppet valves are fully opened, to 
dispense fuel at a relatively high rate. 
In some installations, the rate at which the fuel can be dispensed through 
the nozzle is sufficiently high to cause premature shutoff of the nozzle 
by the automatic shutoff mechanism, and often results in a spitback which 
results in a fuel spill, which can soil the customer's clothing and 
produce pollution and fuel loss. Further, premature shutoffs are annoying 
to customers and often lead them to mistakenly believe that the vehicle 
fuel tank is full when in fact it is not. 
In accordance with the present invention, the automatic flow regulator 24 
is provided at the junction between the lateral passage 33 and the 
downstream passage 34. This regulator automatically functions to limit the 
maximum flow rate of fuel through the nozzle and avoids premature shutoff 
and other fuel spilling problems. 
The automatic regulator 24 includes a sleeve member 51 having a cylindrical 
portion 52 extending from an upper end 53 to a lower end 54. Adjacent to 
the upper end, the sleeve provides spaced first and second external 
annular flanges 56 and 57, respectively. In addition, an inwardly 
extending lip 58 is provided at the upper end 53 of the sleeve. 
The two flanges 56 and 57 are sized to closely fit the interior of the 
lateral passage 33, as best illustrated in FIGS. 3 through 5, and 
cooperate to receive an O-ring seal 59 therebetween. This seal provides a 
fluidtight joint between the sleeve and the lateral passage so that fuel 
flowing through the nozzle must pass through the sleeve 51. The seal 59 
also holds the sleeve secure by means of friction against the body. 
The sleeve 51 is also provided with a plurality of openings 61 peripherally 
spaced around the cylindrical portion at a location spaced axially from 
the upper end 53 of the sleeve. These openings provide substantial 
communication between the interior of the sleeve and the downstream 
passage 34. 
Positioned within the sleeve is an orifice piston 62 having a skirt portion 
63 which closely fits the inner wall of the cylindrical portion 52 of the 
sleeve 51. The piston 62 moves freely in the sleeve. The piston 62 is also 
provided with an inturned flange 64 at its upper end which defines an 
orifice 66 through which the fuel passing through the nozzle must flow. 
This orifice 66 is defined externally by the inturned flange 64 and 
internally by the operating rod 46. Consequently, the orifice 66 itself is 
an annular orifice extending around the operating rod 46. 
A spring 67 extends up along the sleeve 51 and engages the inturned flange 
64 of the piston at its upper end. This spring normally functions to 
maintain the piston 62 in the uppermost position in engagement with the 
lip 58, as illustrated in FIG. 4. In such position, the skirt 63 of the 
piston is above the opening 61 and full free flow of fuel is provided 
through the automatic flow regulator 24. 
When the poppet valve is opened a small amount, as illustrated in FIG. 4, 
the spring 67 exerts sufficient force on the piston to overcome any 
pressure differential acting on the inturned flange 64 as a result of the 
flow through the orifice 66 and the regulator remains in its fully opened 
position. However, as the flow increases through the nozzle when the 
poppet valve is opened greater and greater amounts, or when the flowing 
pressure is increased at a given stroke, a pressure drop occurs through 
the orifice 66 which produces a downward force on the piston. This 
downward force is a function of the upstream pressure. 
When sufficiently high pressure occurs, the pressure drop increases to a 
value sufficiently high to cause the piston to move downwardly against the 
action of the spring 67 to partially close the ports or openings 61 and 
restrict the flow of fuel through the nozzle. The size of the orifice and 
the force provided by the spring are selected so that the piston limits 
flow through the nozzle to a desired maximum predetermined rate, e.g., ten 
gallons per minute. Therefore, if the pump supplying the pressure fluid to 
the nozzle produces sufficient pressure to otherwise cause excessive flow 
rates through the nozzle, the automatic flow regulator operates to prevent 
such excessive flow rates. 
The sleeve 51 is retained by friction to the body by the O-ring seal 59 and 
is butted against the adjacent lateral wall 33a. If, because of the force 
of the spring, a small space opens up between the sleeve and the lateral 
wall, it will be closed in operation since the piston 62 moves down 
against the action of the spring and the spring force is isolated from the 
sleeve. In such instance, the pressure drop through the sleeve orifice 58 
produces a downward force on the sleeve 51, causing it to tightly engage 
the adjacent body wall 33a, as indicated in FIG. 5. Therefore, during 
regulation, substantially all of the flow must pass through the port 
openings 61 where the flow rate is controlled by the piston 62. Thus, the 
controlled flow rate error is minimized over a broad range of pressures. 
It should be noted that the automatic flow regulator requires only three 
significant parts plus an O-ring seal. These parts can be produced and 
installed at very low cost and provide reliable functions. In fact, the 
sleeve and piston are preferably molded polymeric parts which can be 
produced at very low cost. Further, the flow regulator can be retrofitted 
in existing nozzles, and is assembled along with the poppet through the 
opening 41 in the nozzle body. Still further, the provision of a flow 
regulating valve within the nozzle does not require any modification of 
the nozzle proper, and therefore does not increase the overall nozzle 
cost. Still further, because the flow regulating valve is located within 
an existing passage within the nozzle, it does not require a separate body 
element, nor does it require any additional connections which could result 
in leakage problems. 
Although the preferred embodiment of this invention has been shown and 
described, it should be understood that various modifications and 
rearrangements of the parts may be resorted to without departing from the 
scope of the invention as disclosed and claimed herein.