FUEL TRANSFER ADAPTERS

Abstract

A fuel transfer adapter for a fuel cartridge, the fuel transfer adapter comprising: an adapter body; at least one fuel filling channel through said adapter body for the passage of fuel from a valve of the fuel cartridge to a fuel tank of an appliance through a filling port of said fuel tank; a fuel cartridge engaging portion at one end of the adapter body, for engaging the adapter body with the valve of the fuel cartridge; and, a port engaging portion at the other end of the adapter body for releasably engaging with the filling port, whereby the fuel transfer adapter incorporates at least one vent for the passage of vapour from the fuel tank to the atmosphere, said at least one vent being configured, in use, to transfer vapour displaced from the fuel tank by the fuel entering therein to the atmosphere.

A method of filling a fuel tank of an appliance comprising the steps of: docking a fuel cartridge equipped with a fuel transfer adapter to a filling port of an appliance; applying a push force between the appliance and the fuel cartridge to open both a port filling valve and a fuel cartridge valve; applying a further push force between the appliance and the cartridge to create a fluid-tight seal between a compliant rim of the fuel transfer adapter and the filling port, and to create a fluid-tight seal between the sealing lip of a port engaging portion of the fuel transfer adapter and a wall of the filling port; allowing fuel to transfer from the fuel cartridge to the fuel tank of the appliance, and displaced vapour to transfer from the fuel tank to the atmosphere through a vent in the fuel transfer adapter; and, undocking the fuel cartridge from the filling port.

Claims

1. A fuel transfer adapter for a fuel cartridge, the fuel transfer adapter comprising: an adapter body; at least one fuel filling channel through said adapter body for the passage of fuel from a valve of the fuel cartridge to a fuel tank of an appliance through a filling port of said fuel tank; a fuel cartridge engaging portion at one end of the adapter body, for engaging the adapter body with the valve of the fuel cartridge; and, a port engaging portion at the other end of the adapter body for releasably engaging with the filling port, whereby the fuel transfer adapter incorporates at least one vent for the passage of vapour from the fuel tank to the atmosphere, said at least one vent being configured, in use, to transfer vapour displaced from the fuel tank by the fuel entering therein to the atmosphere.

2. A fuel transfer adapter according to claim 1, wherein the vent comprises a channel within the adapter body.

3. A fuel transfer adapter according to claim 2, wherein the channel comprises a substantially cylindrical annular recess about the periphery of the fuel filling channel.

4. A fuel transfer adapter according to claim 3, wherein the cylindrical recess incorporates at least one vent restrictor for controlling the flow of vapour from within the cylindrical recess to the atmosphere.

5. A fuel transfer adapter according to claim 4, wherein the at least one vent restrictor comprises an orifice within a wall of the adapter body.

6. A fuel transfer adapter according to claim 5, wherein the orifice is between 0.01 mm and 6 mm.

7. A fuel transfer adapter according to any one of the preceding claims, wherein the adapter body comprises a sealing lip about the periphery configured, in use, to provide a fluid-tight seal with the filling port when the fuel transfer adapter is engaged with said filling port.

8. A fuel transfer adapter according to any one of the preceding claims, wherein a port-engaging end of the port-engaging portion incorporates a compliant rim configured, in use, to form a fluid-tight seal with the filling port when the fuel transfer adapter is engaged with said filling port.

9. A fuel transfer adapter according to claims 7 and 8, whereby the sealing lip and compliant rim are configured, in use, to form a fluid-tight seal with the filling port under an operating thrust force exerted during filling.

10. A fuel transfer adapter according to any one of the preceding claims, whereby the adapter body is configured, in use, to support the fuel cartridge in the filling port such that the longitudinal axis of the fuel cartridge is substantially parallel with the direction of insertion into the filling port.

11. A fuel transfer adapter according to any one of the preceding claims, wherein the fuel cartridge engaging portion comprises a tubular hub configured to engage with the valve stem of the fuel cartridge through a snap fit or an interference fit.

12. A fuel transfer adapter according to claims 1 to 10, wherein the fuel cartridge engaging portion comprises a skirt.

13. A fuel transfer adapter according to claim 12, wherein the skirt is configured to engage with the fuel cartridge through a friction fit.

14. A fuel transfer adapter according claim 12, wherein a wall of the skirt incorporates one or more projections for engaging with the fuel cartridge through a snap fit.

15. A fuel transfer adapter according to any one of the preceding claims, wherein the fuel transfer adapter comprises a polymer material.

16. A fuel transfer adapter according to any one of the preceding claims, wherein the fuel transfer adapter is injection moulded as one piece.

17. A method of filling a fuel tank of an appliance comprising the steps of: i. docking a fuel cartridge equipped with a fuel transfer adapter to a filling port of an appliance; ii. applying a push force between the appliance and the fuel cartridge to open both a port filling valve and a fuel cartridge valve; iii. applying a further push force between the appliance and the cartridge to create a fluid-tight seal between a compliant rim of the fuel transfer adapter and the filling port, and to create a fluid-tight seal between the sealing lip of a port engaging portion of the fuel transfer adapter and a wall of the filling port; iv. allowing fuel to transfer from the fuel cartridge to the fuel tank of the appliance, and displaced vapour to transfer from the fuel tank to the atmosphere through a vent in the fuel transfer adapter; and, v. undocking the fuel cartridge from the filling port.

Description

[0041] For a better understanding of the invention and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings, in which:

[0042] FIG. 1 shows one embodiment of a fuel transfer adapter in isometric view;

[0043] FIG. 2 shows the fuel transfer adapter of FIG. 1 in plan view, showing one embodiment of a vent;

[0044] FIG. 3A shows the fuel transfer adapter of FIG. 1 in front view, and FIG. 3B shows the fuel transfer adapter of FIG. 1 in side elevation view when attached to a fuel cartridge;

[0045] FIG. 4 shows a diagrammatic view of the fuel transfer adapter being inserted into a filling port of a fuel tank;

[0046] FIG. 5 shows the diagrammatic view of FIG. 4, with fuel transfer adapter further inserted into the filling port and showing the main forces acting between the fuel transfer adapter and the port pintle;

[0047] FIG. 6 shows the diagrammatic view of FIG. 4, showing the fuel transfer adapter yet further inserted into the filling port, showing the displacement of a port sealing washer relative to a port pintle within the filling port, uncovering a fuel admission passageway on the port pintle;

[0048] FIG. 7 shows the diagrammatic view of FIG. 4, showing fuel entering the fuel tank, and displaced vapour passing out of the filling port to the atmosphere via a venting passageway uncovered by the displacement of a port sealing washer relative to the filling port housing; and,

[0049] FIG. 8 shows the diagrammatic view of FIG. 7 with fuel transfer adapter fully inserted into the filling port, a sealing lip in fluid-tight arrangement with a wall of the filling port, and displaced vapour passing to the atmosphere through a vent in the fuel transfer adapter.

[0050] FIG. 9 shows a diagrammatic view of one embodiment of fuel transfer adapter, engaged with a typical fuel cartridge, the fuel transfer adapter and therefore the fuel cartridge shown in an inverted condition, engaged with a filling port of a fuel tank.

[0051] In the figures like references denote like or corresponding parts.

[0052] It is to be understood that the various features that are described in the following and/or illustrated in the drawings are preferred but not essential. Combinations of features described and/or illustrated are not considered to be the only possible combinations. Unless stated to the contrary, individual features may be omitted, varied or combined in different combinations, where practical.

[0053] FIG. 1 shows a fuel transfer adapter 1 for supporting the transfer of a fuel from a fuel cartridge to a fuel tank. The fuel transfer adapter 1 comprises an adapter body 2. The adapter body 2 may be of any suitable shape so as to perform the required fuel transfer, to provide an aesthetic shape, whilst also to support the fuel transfer process. The adapter body 2 may therefore be substantially cylindrical, or substantially conical, or any other such shape that fulfils these requirements. The adapter body 2 may also incorporate means to support a fuel cartridge in an inverted position, when mounted within a fuel tank, to ensure that leakages are unlikely to occur during the filling process.

[0054] The adapter body 2 incorporates at least one fuel filling channel 3. This fuel filling channel 3, when in use filling a fuel tank, is fluidly connected to a fuel store within a fuel cartridge 7, whilst also being fluidly connected to a fuel tank within an appliance 14. The fuel filling channel 3 may comprise a pipe, tube or similar arrangement that allows for an efficient transfer of liquid fuel from fuel cartridge 7 to fuel tank. The fuel filling channel 3 may run down the central axis of the adapter body 2. The fuel transfer adapter 1 may incorporate more than one fuel filling channel 3, not shown.

[0055] The adapter body 2 incorporates a port engaging portion 4 that projects from the adapter body 2, and provides means to connect the fuel filling channel 3 with a fuel tank. The port engaging portion 4 may therefore also incorporate the fuel filling channel 3, to continue the path of the fuel filling channel 3 to fluidly connect with a filling port of a fuel tank. The port engaging portion 4 in one embodiment is substantially oval in cross-section. This shape is configured to assist with orientation and docking of the fuel transfer adapter 1 and therefore the fuel cartridge within the filling port of the appliance. The filling port of the appliance is provided with a corresponding shaped socket to engage with the port engaging portion 4. The fuel cartridge with fuel transfer adapter 1 must be inverted to align with the filling port. The non-circular cross-sectional shape of the filling port 20 is designed to frustrate attempts to fill the appliance using non-proprietary fuel cartridges of unapproved fuel.

[0056] The port engaging portion 4 may be provided with a compliant rim or sealing land, not shown. This compliant rim seals the port engaging portion 4 to a mating wall or walls in the filling port to prevent the fuel from leaking. The compliant rim may be suitably shaped to mate with the filling port, and to ensure that a sufficient compliant rim sealing pressure is maintained against the mating surfaces of the filling port when a filling force is exerted by a user.

[0057] The compliant rim may comprise a flexible material, or may be configured to flex under a force.

[0058] The fuel transfer adapter 1 is also provided with a fuel cartridge engaging portion 5. This fuel cartridge engaging portion 5 in one embodiment comprises an outer skirt and a central hub that are configured to engage with one or more features on the outlet end of a fuel cartridge. This engagement may for example employ combinations of snap fits, friction fits, adhesive bonding, heat staking, welding and crimping. In an alternative embodiment, the fuel transfer adapter 1 may be formed as an integral part of the fuel cartridge.

[0059] As shown in FIG. 2, the fuel transfer adapter 1 comprises at least one vent 6. This vent 6 is configured to allow the passage of vented gases from the fuel tank of the appliance during the filling process. The at least one vent 6 may comprise a channel, or orifice. The channel may run adjacent to the fuel filling channel 3. The vent 6 may be substantially cylindrical and surround the fuel filling channel 3, and share the same longitudinal axis as the fuel filling channel 3. Where the vent 6 is an orifice or hole, this hole may be situated within the adapter body 2 of the fuel transfer device 1, or within a wall of the fuel filling channel 3. The vent 6 is configured to be fluidly connected to the fuel tank of the appliance at one end, to allow for the passage of displaced vapours in the fuel tank during the filling process, whilst also being fluidly connected to the surrounding atmosphere, to vent these gases to the surroundings of the fuel transfer adapter 1.

[0060] The vent 6 may incorporate at least one venting channel restrictor 23, as shown in FIG. 4. This venting channel restrictor 23 may comprise an orifice or further channel, configured to throttle the flow of vapour through the vent 6 and to the surrounding atmosphere 17. The diameter of the throttling orifice may be in the range 0.01 mm to 6 mm according to the requirements of vapour permitted to be released into the atmosphere within a particular region, or according to the requirements of a particular appliance containing a fuel tank. Thus the rate of flow of the venting gases can be altered by using a different fuel transfer adapter 1 that comprises a venting channel restrictor 2 of a lesser or greater throttling effect.

[0061] The dimensions of the venting channel restrictor 23 therefore have a significant impact on the performance of the vent 6, and the quantity of vapour that can be vented at any one time. Territorial regulations are likely to regulate the venting of such flammable, noxious gases and these regulations are subject to amendment by each territory. A range of fuel transfer adapters 1 with different degrees of vent throttling could be made available to ensure compliance over time with evolving venting regulations within a territory of use, up to and including the elimination of venting entirely.

[0062] FIGS. 3A and 3B show a side view and end view of the fuel transfer adapter 1, showing the ovoid shape of one embodiment of port engaging portion 4. FIG. 3B shows the fuel transfer adapter 1 when secured to a fuel cartridge 7.

[0063] FIG. 4 shows an inverted fuel cartridge 7 provided with a fuel transfer adapter 1, and engaged through a port filling valve 9 of a filling port 8. The fuel transfer adapter 1 is also configured to engage with the fuel cartridge valve 10 and fuel cartridge filling stem 11 of the fuel cartridge 7, to form a pressing member that causes fuel to expel from the fuel cartridge 7. FIG. 4 shows the fuel transfer adapter 1 starting to be inserted into the filling port 8. FIG. 5 shows the fuel transfer adapter 1 having been further inserted into the filling port 8, showing an insertion force F2 being applied by a user pressing the fuel cartridge 7 and therefore the fuel transfer adapter 1 into the filling port 8. Also shown is a reactive force Fl of a spring within the filling port 8, this spring not shown in the drawings.

[0064] FIG. 5 shows a sealing lip 22 of the fuel transfer adapter 1 approaching engagement with a port side wall 21 of the filling port. Also shown is the initial displacement of a port washer 24 by the port pintle 25 that governs entry of the fuel into the fuel tank 13. FIG. 6 shows the sealing lip 22 of the fuel transfer adapter 1 even closer to being engaged with the port side walls 21, and the port washer 24 having been further displaced by the port pintle 25. FIG. 7 shows the fuel 15 flowing from the fuel transfer adapter 1 of the fuel cartridge 7, down the fuel filling channel 3 and into the filling port 8 of the appliance 14, the port washer 24 having been sufficiently displaced by the port pintle 25 to allow the passage of fuel 15 to take place. This fuel 15 enters the fuel tank 13, and displaces the gases, comprising air and vapour, within the fuel tank 13. These gases 16 find a suitable escape route out through a fuel tank vent 18, and through one or more fuel tank vent restrictors 19 to the atmosphere 17. This initial flow of gas 16 is not yet caught by the vent 6 within the fuel transfer adapter 1.

[0065] Inside the appliance 14 the port filling valve 9 is connected to the fuel tank 13 via a channel which generally includes one or more orifices or other features restrictive to liquid fuel 15 flow. These restrictions are represented in aggregate by a filling restrictor 20. Venting arrangements for gas 16 inside the fuel tank 13 as it is displaced by liquid fuel 15 are normally provided in such appliances 14. The pressurised vapour/air mixture in the fuel tank 13 is connected to the atmosphere 17 via a separate pathway or fuel tank vent 18 to that taken by arriving fuel 15, and will include one or more orifices or other features restrictive to flow of gas 16, represented in aggregate by the fuel tank venting restrictor 19. The purpose of this venting pathway is to reduce internal fuel tank pressure to below the pressure in the fuel cartridge 7, enabling expeditious filling while avoiding undue loss of fuel.

[0066] This fuel tank vent 18 is therefore within the appliance 14, and therefore it is not easy to alter the performance of this fuel tank vent 18 in order to meet a change in vented vapour regulations for a territory. Or should an appliance 17 be moved from one territory with a specific venting regulation to another with a different venting regulation, the appliance 14 may be rendered obsolete.

[0067] FIG. 8 shows the arrangement of FIG. 7 but with a further force having been applied in a downward direction to the fuel cartridge 7, and therefore to the fuel transfer adapter 1. This further force moves a second sealing lip 22 about the periphery of the adapter body 2 of the fuel transfer adapter 1 into sealing engagement with the port side walls 21 of the filling port 8. This sealing lip 22 may comprise a surface of the adapter body 2 that is configured to mate with the surface of the port side walls 21 in a fluid-tight arrangement. The sealing lip 22 may comprise an additional material such as a rubber or elastomeric lip that provides some compliance to support the sealing process, not shown. The surface of the adapter body 2 may be shaped to form the sealing lip 22 or sealing land when engaged with the filling port 8 of the appliance 14.

[0068] In FIG. 8, with the sealing lip 22 providing a seal with the filling port 8, the displaced vapour 16 passes through the fuel tank vent 18 and fuel tank venting restrictor 19, then is diverted into the vent 6 of the fuel transfer adapter 1. In an embodiment where the vent 6 comprises a channel and venting channel restrictor 23, the vapour 16 must flow to the surrounding atmosphere 17 out through this channel and venting channel restrictor 23 arrangement. The vent 6 may comprise more than one venting channel restrictor 23, not shown. The size of this venting channel restrictor 23 controls the volumetric flow rate of vapour 16 from the fuel tank 13 of the appliance 14, strongly influencing the fuel tank pressure and therefore the fuel inflow rate. FIG. 9 shows the fuel transfer adapter 1 with fuel cartridge engaging portion 5 engaged with a fuel cartridge 7. The fuel cartridge 7 and therefore the fuel transfer adapter 1 are shown in an inverted condition, and releasably engaged with the filling port 8 of a fuel tank 13 of an appliance 14.

[0069] The flow resistance of the venting channel restrictor 23 is substantially greater than that of the internal aggregate venting restriction 19. The flow resistance of restrictor 23 therefore dominates venting rate from the fuel tank 13, and thus the time required to refuel the fuel tank using a pressurised fuel canister.

[0070] By providing the vent 6 within the fuel transfer adapter 1, it becomes an easy process to replace the fuel transfer adapter 1 to alter the venting performance of the appliance 14. The fuel transfer adapter 1 may comprise a one-piece, injection moulded, polymer component that is extremely cost-effective to manufacture. Upon a change of venting requirements, the fuel transfer adapter 1 can be simply replaced with an alternative fuel transfer adapter 1 that incorporates the vent 6 and therefore the venting channel restrictor 23 to meet these requirements. The fuel transfer adapter 1 is effectively a disposable component of the system. The fuel transfer adapter 1 may be recyclable.

[0071] This proprietary filling system in one embodiment may be used for refuelling portable LPG-fuelled appliances with liquid fuels. By embodying this component as a custom fuel transfer adapter 1 fitted to fuel cartridges 7 such as aerosol-type fuel cans and used to dock to the filling port 8 of the appliance 14, high levels of ongoing control of the refuelling process can be enforced by the supplier of the fuel stocks.

[0072] In addition the fuel transfer adapter 1 discourages use of potentially damaging counterfeit fuels by end-users of the relevant appliances 14 such as LPG-fuelled appliances. These portable LPG-powered appliances may include but are not limited to hand-held work tools such as soldering irons, blowtorches, curling tongs, cutting and brazing equipment. It also includes but is not limited to certain compact stoves and food warmers.

[0073] The fuel transfer adapter 1 resolves the conflict between desire for locally-adjustable venting rate and inaccessibility/inadvisability of the venting adjustment by end users by relocating the vent 6 controlling venting rate from inside the appliance to the fuel transfer adapter 1 used for refuelling. It does this by: embodying venting control in a cheap disposable external component, supplied with refuelling fuel cartridges, in place of an internal inaccessible orifice; comprising a moulded component that adds no significant cost to the can adapter; comprising a fixed orifice within a tamper-resistant component it can be supplied in a range of different venting rates, or indeed with no venting at all, as appropriate to the needs of each territory; should it become necessary to alter the venting rate of all appliances within a territory, no field recall is required; provide variants of the can adapter with differing venting rates simply by changing the orifice size and resistance.

[0074] Upon manufacture of the fuel transfer adapter 1, the venting rates of each unit are controlled by an interchangeable core pin in the mould tool of an injection moulding machine. Colour coding of the moulding or ink-jet printing onto the exterior of the moulding can be used to differentiate visually identical can adapters of differing venting characteristics.

[0075] The tamper-resistant installation of the fuel transfer adapter 1 onto the fuel cartridge 7 combined with a unique filling adapter for the appliance 14 discourages end-users from recycling fuel transfer adapters 1 from obsolete empty fuel cartridges 7 onto non-approved fuel cartridges with different vapour pressure, filling behaviours, combustion characteristics or purity. These features of the fuel transfer adapter 1 also discourage end-users from omitting the fuel transfer adapter 1 entirely and performing refuelling directly from fuel cartridge 7 with unregulated venting.

[0076] The overall effect of the fuel transfer adapter 1 as part of the appliance refuelling system is that the manufacturer of the appliance 14 and the fuel cartridges 7 has a high degree of control over how refuelling is performed by end-users, and can adapt this independently in different territories over time should this become necessary.

[0077] The method of filling a fuel tank 13 of an appliance 14 may comprise the steps of initially docking a fuel cartridge 7 equipped with a fuel transfer adapter 1 to a filling port 8 of an appliance 14. The user applies an initial force F2 to open both the filling port valve 9 and fuel cartridge valve 10. This starts the flow of fuel 15 to the fuel tank 13. When the user applies a slightly greater push force F2, a fluid-tight seal is created between the sealing lip 22 and the port side walls 21. The displaced vapour 16 from the fuel tank 13 is transferred to the atmosphere 17 through the vent 6 in the fuel transfer adapter 1.

[0078] In one embodiment of the invention the refuelling completion signal is the appearance of atomized liquid emissions in the vapour 16. In another embodiment the refuelling completion signal is a change in the character of the noise emission from the vent 6 optionally accompanied by perceptible vibration of the fuel cartridge 7. In a further embodiment the refuelling completion signal is provided by the measured weight of the appliance 14 falling within a desired range. In yet another embodiment of the invention the refuelling completion signal is provided by a liquid fuel level indicator, not shown.

[0079] The refuelling control system disclosed herein may be applied to any consumable replenishment or dispensing operation where effective control of emission levels, or counterfeiting of consumable, or enforcement of safe or regulated filling rate is desirable. Examples include but are not limited to: the infusion of hot water through single-use, individual branded coffee packs at a controlled rate, where flavour and strength of a drink is a function of infusion rate; fuel transfer between LPG vessels where for safety reasons concentration of vented vapour in ambient air needs to be maintained below a combustion threshold; and, in certain types of domestic hot water cylinder installations in elevated locations, where cold water replenishment rate is less than the water abstraction rate, and where a danger of pump cavitation or tank buckling due to sub-atmospheric pressure can arise.