1. Field of the Invention
The present invention relates to a refueling coupling.
2. Description of the Related Art
Road vehicles are usually refueled with a so-called “gravity” refueling nozzle to which fuel is pumped under pressure, but from which the fuel flows under gravity into a vehicle's filler neck or refueling coupling.
Many air-borne and some other vehicles are refueled with a pressure refueling nozzle, which is fluid-tightly connected to the vehicle's refueling coupling.
Some vehicles do indeed include both types of refueling coupling. This is expensive, bulky and introduces a weight penalty on an aircraft.
As used herein, the term coupling is used to mean the vehicle side connector; whereas the term nozzle is used to mean the refueling vessel and refueling side connector. We are aware that this terminology is not universal and that in other regions the term coupler is used to mean the hose side connector.
Also as used herein, the term dry-break is used to mean that the coupling and nozzle are adapted to be both sealed when not connected to each other.
The object of the present invention is to provide a combined pressure and gravity refueling coupling.
According to a first aspect of the invention there is provided a refueling coupling having:
Normally the main displaceable dry-break member will be translationally displaceable against a return spring. Such an arrangement is possible for the subsidiary displaceable member. However in the interests of allowing the “gravity” nozzle to penetrate past the subsidiary displaceable member, the latter is preferably pivotally connected to the main dry-break member. Conveniently, the pivot is provided with a spring for returning the subsidiary member to its normally closed position. Preferably the main and subsidiary members are adapted for sealing of the subsidiary member to the main member, whereby full dry-break operation is available when pressure refueling.
Insofar as the coupling may be provided separate from a fuel tank, that is in a vehicle skin, and/or the tank may be flexible, the main dry-break member is preferably mounted on rods extending from fitting and having springs for returning the dry-break member back the to the fitting and a hose is provided around the rods for connection to both the fitting and the tank. The inner ends of the rods can be carried on the annular member or at least a sleeve being an integral extension of the annular member or on an abutment member in the form of a spider or a ring.
Preferably the coupling is provided with an air vent having a float arranged to close as the tank fills for causing back-pressure in the connector when the tank is full. Additionally an airflow restrictor is preferably provided in an air vent duct. The restrictor is preferably adapted to open to a limited extent to accommodate gravity refueling air escape and to a greater extent to allow an increased air flow in the case of pressure refueling, with its great fuel flow.
According to a second aspect of the invention, there is provided an adapter for a refueling coupling as claimed in any preceding claim, the adapter being generally tubular and having:
To help understanding of the invention, a specific embodiment thereof will now be described by way of example and with reference to the accompanying drawings, in which:
Referring to the drawings, the refueling coupling there shown has an annular fitting 1 having a bore 2, bayonet lugs 3 and slots 4 suiting it for connection to a pressure filling nozzle 50. A dry-break member 5 is provided within the annular fitting, normally sealing to it with the aid of an O-ring seal 6. When the pressure filling nozzle is fitted, the dry-break member is depressed allowing fuel to flow. In this respect, the refueling coupling is conventional.
In accordance with the invention, the dry-break member has a central aperture 11, normally closed by a side pivoted flap 12. The pivot 14 is at a pin 15 carried in lugs 16 on the underside of a central disc 17 having the aperture 11. The flap has a finger 17 projecting between the lugs and having the pin passing through it. A spring 18 is carried on the pin and normally biases the flap into its closed position parallel with the disc. An O-ring 19 is carried on the flap whereby should unusual forces displace fuel against the flap it does not leak.
For gravity nozzle fuelling, as shown in
The fitting 1 has three rods 21 secured to the underside of a fixture rim 22. The dry-break member has three projections 23 with bores 24 through which the rods project. Lower ends of the rods are fast in a spider 25. The rods carry springs 211 which normally bias the dry-break member into sealing contact with the fitting 1.
For pressure refueling, the pressure refueling nozzle 50 is latched on and operated to cause its dry-break member 501 to physically displace the member 5 for flow of fuel around it. Should de-fuelling be required through a pressure refuel nozzle, in the case of the vehicle having the refueling coupling, it should be noted that the flap 12/disc 17 does not inhibit this because scavenged fuel can flow around the dry break member 5 which is displaced from its seat in the annular fitting 1.
In the embodiment of
Also mounted in the tank plate 29 is an air vent 33 in the form of a duct 34 secured via a rim 35. Tube carries an apertured ball retainer 36 which retains a buoyant ball 37 and a dense ball 38. The latter is for forcing the buoyant ball to seal in a vehicle inversion. The buoyant ball seals during refueling by floating against a seat 39 above the cage. Above the seat, an airflow limiting disc 40 is urged against the seat by a spring 41. The disc is open centrally 43 and carried on an apertured sleeve 42 carrying the spring 41. The sleeve is secured by a cross pin 44, against which the spring reacts. Internally of the sleeve a second spring 45 urges a inner sealing disc 46 into the central opening 43 of the disc 40. Features 42, 45 & 46 are shown in
During gravity nozzle filling air pressure lifts the inner disc 46 against the light spring 45 and flows through the disc and up through the apertures 42 in the sleeve. Thus a pressure marginally above ambient is maintained in the tank, for quick closure of the nozzle's trigger when the tank is filled to the extent that the buoyant ball 37 seals against the seat 39.
When pressure nozzle filling, the air flow is too great for the apertured sleeve and the air pressure in the tank lifts the disc 40. The latter with the action of its spring 41 keeps the pressure just above ambient, for again causing the fuel flow to be shut off by detection of pressure rise when the buoyant float seals.
To vent tank air to atmosphere, a hose 47 extends up from the vent 33 via a deflector 48. This and the fitting 1 are housed in a depression 55 in the skin. A hinged closure 56 is provided for closing the depression, whereby the external lines of the vehicle are little disturbed by the single refueling fitting of the invention.
Alternatively to the above use of hoses, the fitting can be fast with a tank via its rim 22.
The invention is not intended to be restricted to the details of the above described embodiment. For instance, as shown in
Further, as shown in
The male-end piston 306 is flat for dry-break co-operation with a displacement member 308 of the pressure refueling nozzle 309. It carries a peripheral sealing O-ring 310 on its periphery 311, which is tapered for abutting with a seat 312 in the adapter. This abutment determines the position of the piston 306 under the action of the spring 305. Towards the other end of the adapter, it has a spider 313 with a central aperture for a rod 314 inter-connecting the piston 306,307. The spring acts between the spider and the inner side of the piston 306.
The piston 307 is similar in having an O-ring 315 carried in its parallel periphery 316. The adapter has a parallel bore 317 at this end, with which the piston 307 seals when in its normal position. On refueling use, the female-end piston 307 moves out of the bore 317, and co-operates in a dry-break manner with the member 310 of the refueling coupling.
The invention is not intended to be restricted to the details of the above described embodiments. For instance as shown in
This application claims priority to and takes the benefit of U.S. Provisional Application Ser. No. 61/639,583 filed on Apr. 27, 2012, the contents of which are hereby incorporated by reference.
Number | Date | Country | |
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61639583 | Apr 2012 | US |