GB2404182A - Delivery nozzle with flow control valves - Google Patents

Abstract

A secondary valve (80) is fitted, as a self-contained insert, within a discharge nozzle spout (25) of a flow delivery controller, such as a garage forecourt fuel gun dispenser (20), and is operative in conjunction with a primary regulator and control valve (28) to inhibit spillage, by temporary containment of discharge residue within the spout between successive discharge cycles; the configuration allowing retro-fit adaptation of existing nozzles.

Description

Delivery Flow Valve 24041 82 {Dribble Inhibitor}

Background

This invention relates to delivery flow control, to address inadvertent spillage and attendant wastage.

As such it is particularly, but not exclusively, concerned with fuel conservation, such as fuel (motor spirit) dispensing from a filling station garage forecourt to a motor vehicle fuel tank.

More specifically, an objective is to inhibit discharge nozzle drip.

Although the emphasis is upon fuel - as a precious energy medium derived from a finite natural resource - the principles apply to wider liquids, or even solid particulate (powder) flowing media.

Thus, in a wider industrial and commercial context, other diverse examples might include beverages, flowable powders or medical applications.

Problem In discharge regulation and control a residue may arise downstream - and so beyond the scope or control - of a dispensing regulator valve.

Moreover, the residue may prove difficult to drain or exhaust - for reasons not necessarily entirely understood - but which may (speculatively) reflect surface tension attendant surface wetting and inadequate venting against air lock effects.

Exposed residue may itself entrap dirt, debris and precipitates.

Thus discharge residue represents wastage, but also a contaminant possibly even hazardous.

In a pressurized delivery, once a primary regulator À valve has shut-off a supply, reliance is typically placed À À' upon gravity drainage of any downstream residue. '.

Pressure rapidly decays downstream of the primary valve and surface tension, boundary layer, velocity À: gradient, flow separation, viscosity or surface friction. . . effects progressively counter fluid run off from.

wetted internal (discharge nozzle) surfaces. À Àe 1:. Àe

Thus, conventional fuel delivery valves entrap, or allow entrapment of, a residual quantity of fluid (fuel) downstream of a regulator valve.

In practice this entrapment cannot be completely exhausted, [whether passively, by patient waiting, or pro-actively by shaking] - and so is typically wasted through inadvertent spillage at a delivery station.

Taken individually, the entrapped volume may seem insignificant or trivial - although informal measurement trials by the Applicants have shown amounts between some 5ml and 20ml.

Nozzle Control / Discharge Configuration It is convenient in configuration, construction and use to locate a primary flow control and regulator valve somewhat upstream of a nozzle outlet spout.

This keeps the discharge away from the operator and safely' into the mouth of a tank fill passage.

This is particularly so in a fuel delivery context, where a handle and valve operating trigger are conveniently juxtaposed - so a finger pull trigger can be operated while gripping the handle - yet the delivery point is somewhat (say, 5-10 inches, circa 12.5-25.5cm) remote.

A nozzle outlet spout represents a volume downstream of regulation and control by a primary valve - and yet one which can prove stubbornly resistant to complete exhaustion by drainage.

Alongside spout drainage are considerations of high supply rates and venting of displaced tank air.

Tank Venting & Automatic Valve Shut-Off Tank fill requires venting of displaced air and volatile evaporative fumes.

Advantage can be taken of this displacement to, À À ' . monitor fill progress and determine delivery shut-off À without over-fill and spillage. . It is common to employ automatic shut off valves in.

fuel delivery or dispenser systems. ' ' Thus, in one approach, an air flow sensor monitors.

fuel tank replenishment by change in displaced air and upon tank fill trips an over-ride coupling, disabling the fuel trigger and halting the fuel flow.

An isolated air flow passage is commonly integrated into the nozzle, to communicate between tank fill pipe and a valve trigger.

Conventional automatic shut off valves still leave residual fuel in a spout downstream of the valve which cannot be drained totally or adequately.

Speculatively, contributory factors may be that, for private motor vehicles, nozzle handle and spout orientation are configured for ease of use upon delivery.

That is, a nozzle is slightly canted with respect to a handle - which sits generally upright in a pump holder and is held generally horizontally upon insertion into a vehicle tank filler passage mouth.

Nozzle orientation and interfit with a downward tank fill pipe impedes upending or inversion for drainage.

Fuel may also be entrapped in the nozzle vent passage.

Only upon removal of the nozzle from the fill pipe can it be more downwardly inclined.

Indeed, this generally happens naturally with a relaxing of wrist support action, and this is when dribble discharge arises.

Even upon careful nozzle return to a pump docking station the next user suffers from unexpected dribble when the nozzle is removed and re orientated downwardly to a tank filler pipe - even before a fresh delivery cycle has commenced.

Commercial vehicle filler nozzle variants may feature an abruptly cranked handle and nozzle configuration, which should facilitate spout gravity drainage - but air lock and surface tension effects may still entrap fuel in the nozzle, with attendant wastage dribble. , ,

Prior Art À ' " "

Patents Various earlier proposals have been made to address....

the problem of nozzle drip. Thus, by way of non

exhaustive background, attention is drawn to:

3.. :.

US 5,645,116 McDonald - non-drip liquid dispensing nozzle, but with a cumbersome and vulnerable external spring stopper at a nozzle outlet.

US 5, 620, 032 Dame - retro-fit anti-drip nozzle valve for fuel dispensing nozzles using C-spring mounted rubber flap valves. These are insecure, fragile and vulnerable to interference.

US 6,520,222 Carmack et al - vapour assisted fuel dispensing nozzle with interconnected spring 1 0 biassed poppet regulator valve and recessed ball valve at discharge end.

US 4,331,187, US 3,648,894, US 6,491,282 teach various liquid dispensing valve configurations with refinements such as flow anti-shock conditioning.

1 5 WO 02/087969 and WO 03/010022 teach fuel dispensing nozzle elaboration respectively with interactive user interface and shroud interaction with a fuel tank filler neck.

DE 29516051 (Ehlers) - nozzle drip inhibitor with spring-biased stopper toward nozzle tip, to allow liquid through-flow only upon sufficient pressure.

FR 2714900 (Elf) - nozzle drip inhibitor, with spring biased stopper toward nozzle base, to allow liquid through-flow only upon sufficient pressure.

US 5377729 (Peep) - nozzle drip inhibitor, with spring-biased stopper stem supported by fixed stand toward nozzle tip.

Proprietary Non-exhaustive examples of proprietary automatic dispensing nozzles are those of OPW Fuelling Components (Dispensing Products), of Cincinnati.

Ohio, USA.

Health and Safety, Fire, etc regulations prescribing dispensing nozzle requirements can be found inter. ' s alla at internet web site ret: , www. gepower.com/geooilandgas/en us/ . '' prod_solutions/fuel_dispensers Some nozzle valve variants are also configured to.

shut-off upon upright orientation for return to the, , pump, but this still leaves a downstream residue. À 4:, 1 Residue Discharge Residual fuel is inadvertently discharged and spilled over the vehicle (creating unsightly and even harmful paintwork stains or discolouration) or filling station forecourt upon removal of the nozzle from a vehicle fill neck and re-orientation for docking back at a fuel I pump.

Health & Safety For low volatility fuels, such as diesel, accumulated ground spillage creates a slippery hazardous surface and unsavoury environmental fumes.

Accidental spillage or leaks can cause respiratory problems, dermatitis or chemical burns.

The forecourt surface thus becomes progressively slippery and so hazardous to pedestrians.

Quantification As recognized, the individual amount per delivery is modest, but cumulatively, wastage through spillage is significant.

Wastage represents fuel metered through the pump and thus paid for by the consumer. I It may be disregarded in an individual transaction, but represents a proportionately greater fraction of total delivery for modest purchase.

From a wider environmental perspective, the cumulative wastage represents a notable issue.

Cost Savings Applicants' informal calculations suggest À Residual fuel averages 5 -10ml - equating to annual 1 litre per vehicle wastage.

This represents a modest, but cumulatively.' ' worthwhile cost saving to individual motorists.

À Extrapolated over some 29 million UK vehicles in 2001 - annual wastage totals.

some 6.8 Million Imperial gallons (31 Million.

litres). ': À 1 1 t t I. 5:, . . À At 4.55 litres per gallon, and at nominally ú0.82 per litre, this represents an overall potential annual saving of ú25,420,000.

Corresponding USA estimates indicate...

For 191,275,719 licensed US drivers in 2001, and 1 refuelling per week, represents an annual total wastage spillage of 45,006,049 US gallons (170,366,428 litres); Conservation 1 0 From a wider industry, socio-economic and political perspective Potential savings for UK & USA motorists would be some 51.8 Million Imp Gallons (235.5 Million litres) per annum.

1 5 Over a five year period, potential world-wide fuel saving could exceed 1 billion Imp gallons (4.55 billion litres).

The cumulative effect is thus difficult to ignore.

Statement(s) of Invention

An in-line secondary automatic shut-off valve, at or adjacent the output end of a liquid dispenser delivery line - such as a fuel dispenser at a petrol filling station and configured to inhibit liquid spillage and attendant wastage [or evaporation] of residual liquid in a delivery nozzle downstream of a primary control or regulator valve.

In a particular construction An adjustable secondary valve closure bias, such as a variable tension valve spring, may be employed to allow setting to individual locations and flow delivery characteristics.

Primary shut-off valves may themselves be ' configured to avoid shock reaction loads upon the. ^ pump and pump drive motor.

The secondary valve must not impede high delivery ': volumetric flow rates, nor communication of À À . . displaced tank air to trigger primary valve disabling. . . À . 6 À, Ready Installation It is envisaged that the secondary valve could be configured readily and securely to fit into existing filling station fuel dispenser nozzles.

Diverse valve configurations are feasible, including poppet, spool, diaphragm, rotary, etc. in addition to the particular embodiments described herein - in which a simplified approach is adopted to convey generic operational principles and requirements.

1 0 Resolution - Rationale Provision of a secondary valve according to the present invention thus addresses the problem of spillage, by allowing temporary entrapment - ready for release (driven by pressurised upstream discharge of more liquid) at the next delivery cycle.

This residual entrapment or confinement is kept secure from access by a secondary valve, configured to inhibit vapourisation which might otherwise represent a fire hazard.

This means that each delivery cycle is prefaced with a supplementary (unmetered, or rather previously metered) release of entrapment liquid at no cost to the immediate recipient - albeit who in turn relinquishes a corresponding metered entrapped residue at the end of that delivery cycle.

Thus the beneficiary in turn bears the cost of undelivered residual liquid at the end of the metered discharge, contained ready for release to a follow-on delivery.

Fluid Diversity Although the prime example of a secondary valve according to the present invention concerns fuel delivery systems, it is envisaged that other diverse fluid dispensing applications may also be admitted.

For example, fluid delivery in a medical context or.

beverage delivery at a bottling plant. ' '' :'''' Terminology The terms 'secondary' is used herein for ': convenience to differentiate from another 'primary' .. , module, but does not necessarily signify absolute or À relative importance, precedence or priority in action. 7.9 I Be

Embodiments

There now follows a description of some particular

embodiments of a spillage inhibitor according to the invention, by way of example only - in a fuel (especially motor spirit) delivery context - with reference to the accompanying diagrammatic and schematic drawings, in which: Figures 1A and 1B show longitudinal sectional views, in different operating conditions, of a (secondary) shut-off valve, according to the invention, configured such as for a fuel delivery discharge nozzle; More specifically: Figure 1A shows the valve closed to shut-off (fuel) throughflow, by isolating inlet and outlet sides; Figure 1B shows the valve of Figure 1A open, to allow (fuel) through-flow (depicted by hollow arrows), by interconnecting inlet and outlet; Figure 2 shows a part cut-away view of a fuel delivery gun with pistol grip handle, valve operating squeeze trigger - and discharge nozzle outlet spout fitted with a secondary valve according to the invention; Figures 3A through 3C show a variant secondary valve of Figures 1A and 1B respectively, with a vent through passage in a side wall, isolated from a fuel delivery passage, and for connection to a pressure or flow sensor (not shown) for automatic trigger of a primary valve (again not shown); More specifically: Figure 3A shows a valve in a closed condition, with no vent through flow; Figure 3B shows the valve of Figure 3A in an open condition with attendant vent through- flow; and Figure 3C shows valve closure with displaced air.' ' ' ' inhibit signal to a remote primary valve automatic ' ' ' ' shut-off sensor; ,,,,: Figures 4A through 4C show variant installation configurations of a secondary valve, such as of ' Figures 1 A and 1 B. at the end of a delivery nozzle....

discharge spout outlet; . . À '. 8:

More specifically: Figure 4A shows a secondary valve body contained entirely within a discharge nozzle as an internal sleeve, with internal flow cross-section preserved by a stepped spout wall profile; Figure 4B shows a secondary valve body fitted upon one end of a discharge nozzle with a threaded stub interconnection; Figure 4C shows a secondary valve body fitted upon one end of a discharge nozzle with a pinned sleeve interconnection; Figures 5A and 5B show fitment of an anti-tamper guard in the secondary valve of Figures 1A and 1B; More specifically: Figure 5A shows a perforated anti-tamper guard, configured as a perforated disk, located by a threaded end collar also locating a valve bias spring; Figure 5B shows an end view revealing an anti tamper guard perforated end face profile; Figures 6A through 6C show successive operating conditions for a delivery system with co-operative primary and secondary valves; {NB. For convenience of illustration, flow passages are simplified and depicted either full or empty - albeit intermediate, partially filled conditions may exist.} More specifically; Figure 6A shows the delivery system in a closed condition, with fuel in a feed hose, but isolated from a discharge nozzle; Figure 6B shows the delivery system of Figure 6A in an open condition, with fuel flow from a pump (not shown) to an umbilical delivery hose and thence through in-line primary and secondary valves to a. *' ' ' discharge nozzle spout outlet; 2 Figure 6C shows the delivery system in shut-off condition, similar to Figure 6A, but with residual fuel.

entrapped within the discharge nozzle spout by the ' .' secondary valve; À À . . Figures 7A through 7C show installation of a vented 9.' secondary valve, such as of Figures 3A and 3B, in a discharge nozzle of a delivery gun; More specifically: Figure 7A shows a pistol grip valve with trigger released and primary and secondary valves closed; Figure 7B shows an enlarged sectional end detail of a discharge nozzle, with secondary valve, vent passage and air pressure feed tube; and Figure 7C shows an end view of a discharge nozzle with exposed air vent and fluid (fuel) delivery outlet; Figures 8A through BE show a variant secondary valve arrangement, with a poppet valve plate fitted to one end of a sleeve insert; More specifically: Figure 8A shows an overall view of delivery gun, with a secondary valve insert within its discharge nozzle outlet spout; Figure 8B shows an enlarged sectional detail of the secondary valve of Figure 8A in a closed condition; Figure 8C shows the secondary valve of Figure 8A in an open condition; Figure 8D shows an external end view of the closed valve of Figure 8B; Figure BE shows an external end view of the open valve of Figure 8C - with notched valve plate to fit around a nozzle breather vent; Figure 9 shows a longitudinal sectional view of a variant secondary valve configuration of Figures 8A through BE, with end face seal; Figure 10 a variant secondary valve configured as a bonded sleeve insert; Figure 11 shows a variant secondary valve with À'' profiled valve stem to preserve valve closure plate ' orientation in relation to a valve seat with intervening vent aperture; Figures 1 2A and 1 2B show a variant secondary valve... . arrangement with integrated valve stem support and À valve body; À:::: ' ' More specifically: Figure 12A shows a side cross-sectional view of a valve housing - with spring- biased valve member and nozzle end depicted in dotted outline; Figure 12B shows an end view of the valve housing of Figure 12A - with nozzle end depicted in dotted outline. +++

Referring to the drawings, the particular examples of (fluid) spillage inhibition are in the context of fuel (motor spirit) delivery, such as at a garage forecourt pump dispenser - albeit with wider applicability to other fuels, liquids or flowable media.

In some circumstances, a secondary valve according to the invention is retro-fitted, to adapt an otherwise conventional delivery gun for spillage inhibition.

It may thus prove more feasible and economic to supplement a primary valve function rather than re design and replace and risk compromising satisfactory primary valve operation.

With this rationale, the secondary valve can be dedicated to residual (relatively) low pressure entrapment.

In other cases, a delivery gun has integrated primary and secondary valves.

Generally, a delivery control includes a primary [flow regulator and control] valve 28, located within a gun housing 20, itself configured as a pistol grip handle 21, with an operating trigger 23 within a guard 22, fitted in line with an umbilical pump hose 24.

In the particular secondary valve configuration illustrated, a floating valve member 12 has a bull nose 18, with modest locating and angular travel limit ridges 19, to co- operatively interfit with waisted seat faces 16 of a venturi restrictor 15 in a valve body 11. ' Opposite end of valve member 12 has a tapered stem 17 configured as a locating nose within a bias spring 13 of conical form upon a location seat 14.À A secondary valve 10 according to the invention isÀ;..

fitted at, or closely adjacent, a discharge end of a 11.

outlet spout 25 or nozzle, to operate in conjunction with primary valve 28.

Trigger 23 has a direct connection with primary valve 28, only disabled upon remote sensing of a tank fill condition, whereupon the trigger 23 is disabled and the primary valve 28 closed by a spring bias action.

Such automatic fill trigger off is known per se, such as

in the aforementioned prior art references.

Co-operative Primary & Secondary Valve Action However, co-operative interaction with a secondary [downstream] valve poses special considerations.

Thus, when the primary valve 28 is open, flow pressure opens the secondary valve 10, by flow pressure upon end face of valve member 12 overcoming closure bias of spring 13.

ON/OFF Cycle Figures 6A through 6C depict an On/Off cycle sequence.

Conversely, when fuel flow pressure in nozzle 25 passage reduces, secondary valve 10 also starts to close, under the default bias of a valve actuator compression spring 13 upon valve member 12.

Spring Bias Adjustment [Optional] provision is made for adjusting valve 10 operational bias under spring 13 set pre compression, through a threaded fitment of locating collar 14 in valve body 11.

Internal locating flats or end holes (not shown) in collar 14 may be provided to facilitate its (rotational) adjustment.

Spring 13 reaction tends to lock the threaded mounting of collar 14, but a lock washer or sealing gland (not shown) may be fitted to preserve settings. , Tamper Guard,, ', Provision (not shown) may be made for securing valve body 11 within nozzle spout 25, to inhibit inadvertent (casual impact) displacement, or, deliberate prising / insertion interference to gain À. . access to residual entrapped fuel contents.

Similarly, an outlet guard, such as perforated disc 51 in Figures 5A and 5B, may be fitted to nozzle or spout outlet mouth, to obstruct access to valve member 12.

The perforation or mesh density allows this without unduly undermining through-flow capacity, or engendering fuel aeration or foaming.

As depicted in Figures 3A and 3B, an air vent passage 31 in the valve body 11 communicates with 1 0 displaced or vented air from a tank being filled and so preserves action of an automatic fill shut-off trigger.

In one type of automatic trigger, such return displaced air flow is used to create a vacuum condition at a control diaphragm, which - when 1 5 interrupted by return (fuel) - engenders a diaphragm movement unlatching operating trigger 23 from primary valve 28.

As indicated, secondary valve 10 is depicted as an insert for retro-fit in an existing nozzle 25, but could be integrated within the body of a nozzle 25.

Figures 4A through 4C show variant retro-fit mounting arrangements with modest nozzle spout modification.

Thus, as in Figure 4A, secondary valve 10 may be located completely with a spout 25, with a fine pitch longitudinal threaded interconnection 41 along the entirety of valve body 11, with a stepped spout wall and with an intervening abutment seal 42.

Figure 4B shows a shorter coarser pitch threaded interconnection 43, again with abutment seal 44.

Figure 4C depicts an interference fit (ie push-on / pull off) stub interconnection, with abutment seal 46 and locating ring or circumferential restraint pins 47.

Valve Roles À Secondary valve 10 could be configured to have an " ' ' ancillary role as an independent fail-safe leakage À . . .: shut-off back up to primary valve 28, without necessity of direct interconnection. . :' Thus leakage from primary valve 28 into nozzle spout....

25 is contained upon closure of primary valve 10. ..

Venting Figures 7A through 7C show secondary valve adaptation and installation to preserving automatic vent trigger shut-off of primary valve 28 upon sensing a fill condition.

Thus, an existing vent tube 71 within nozzle spout is connected through a mounting ferrule 72 to through passage 31 in the secondary valve body 11, in the manner of Figures 3A and 3B.

1 0 A breather or vent passage 31 is thus preserved alongside discharge passage 73 at the spout end.

Figures 8A through BE show a secondary poppet valve 80 with a valve (closure) head plate 82 mounted upon a barrel sleeve valve body 81.

1 5 A valve stem 83 guides the valve plate 82 throughout its longitudinal movement, generally along or parallel to the axis of nozzle spout 25, and carries a closure bias spring 84.

Spring 84 is operative between a stem head abutment 85, with optional provision for (screw) adjustment, to set required spring pre-compression, and an end carrier spider 89 of the valve sleeve 81.

Valve sleeve 81 is held captive within spout 25 by one or more radial pins or grub screws 87.

Secondary valve 80 closed configuration presents a generally 'blank' shielded nozzle end, as shown in Figure 8D - inhibiting interference.

Valve 80 may be fitted at, or (as Figures 8B and 8C depict) marginally inset from, the spout 25 end, so that, in a valve open condition, of Figure BE, valve plate 82 remains within, or extends marginally proud of, the spout 25.

Throw, or range of travel, of valve plate 82 is set by valve stem 83 and limit stop abutment 85.

Discharge pattern may be directed outward, as " ' ' indicated in Figure 8C, towards a tank filler neck wall. ... . . Inner face (say conical) profiling of valve plate 82.

could preserve orderly discharge flow capacity. À ' Multi-plate (say, spool) valve members (not shown) À could distribute the closure sealing burden.

44.,. ' A notch 'N' in valve plate 82 preserves breather venting upon valve closure - through an inboard pipe 86 set within a ferrule mount 88.

Figure 9 shows a supplementary valve plate seal 91, juxtaposed between and carried by either one or both of valve plate 82 or sleeve body 81.

Figure 10 shows circumferential seal bonding 101 of valve sleeve 81 within nozzle spout 25.

Figure 11 shows adoption of a profiled valve stem 1 0 113 to preserve (rotary) alignment of valve plate 82 with a breather vent aperture.

Figures 12A and 12B show a variant secondary valve with integrated valve housing 124 including stem support 123 and valve body 121.

1 5 Valve housing 124 may be retro-fitted, or integrated, into the end portion of nozzle sprout 122.

Valve body 121 is a snug interfit within nozzle 122 to hold secondary valve 120 securely in place and inhibit liquid through flow between outer valve housing 124 and inner nozzle 122 surfaces.

Support legs 125 connect valve body 121 with support stem 123.

A valve member 130 - depicted in broken outline in Figure 12A - sits within support stem 123 and extends radially outwardly to provide a conical foot 131 seal.

Valve member 130 carries a closure bias spring 132 between stem support 123 and valve head 133.

In closed configuration (i.e. under primary valve shut off) spring 132 is allowed to relax and force head 133 away from stem support 123, thus bringing valve foot 131 within nozzle 122 mouth to seal nozzle contents within.

In operation (i.e. with primary valve open), liquid flows through nozzle 122 and along passageways,,, :, 126 and 127 around valve housing 124 until it contacts valve foot 131 inner surfaces 134.

Under normal operating conditions, fluid pressure at, foot 131 inner surfaces 134 will overcome spring 132 À . . bias and force foot 131 beyond the end of nozzle À;' 122.

This is turn compresses spring 132 between head 133 and stem support 123.

Once foot 131 is extended beyond nozzle 120 end, liquid can flow around foot 131 edge and out of nozzle 122.

When the primary valve is closed and no more liquid is released into nozzle 122, the pressure upon foot 131 is gradually reduced.

1 0 As this force weakens and becomes less than the force of compressed spring 132, the spring force will dominate and act to retract valve member 130 back within nozzle 122.

Thus, foot 131 will return to its sealed position so any 1 5 residue within nozzle 122, without sufficient pressure to open valve 120, will remain contained within.

Advantages of this secondary valve arrangement over, say, arrangement 80 include: À valve member longitudinal stability - through extended stem support barrel; and À prompt, consistent, reliable closure.

Insofar as a secondary valve creates additional wetted surfaces, which may themselves be slow to drain, each successive discharge effectively flushes out or purges residue from the preceding cycle.

This in turn helps avoid accumulated deposits of contaminant debris or precipitates.

Secondary valve pre-loading bias can be set to promote shock discharge,for residual contents flush, without undermining primary valve action.

Secondary valve motion - such as a rotary and/or flip or snap-action valve member - might promote - ', residual discharge and/or secure closure.

Secondary Valve Rationale Ideally, the aim of a delivery flow system is to completely deliver a liquid material to a desired. , location, without residue within the delivery system À . .' downstream of a (primary) delivery flow valve.

In practice, however, this is extremely difficult to achieve - due to many factors including surface tension and air-lock effects.

Thus, rather than attempting to perfect a completely drip-free system, it may be more feasible to configure a system which allows a much reduced drip rate.

Such a system may still have a net (cumulative) advantage.

Further, attempting to reduce residue through primary valve adjustment would be a complex and likely expensive undertaking due the high pressure forces involved.

Thus, a low pressure minimal secondary drip containment valve would seem an economical 1 5 alternative.

Mix and Match Whilst it is not practicable to show every feasible combination and permutation, various features identified may be selectively 'mixed-end-matched' to meet particular requirements.

Component List secondary (anti-spill) valve 11 valve body 12 valve member 13 bias spring 14 bias adjustment collar venturi / restrictor 16 valve seat 17 valve taper 18 valve head 19 locator upstand delivery gun 21 pistol grip 22 handle guard,', 23 trigger 24 delivery hose. ,, discharge nozzle / spout 26 discharge outlet 2 8 primary valve À 31 vent passage À... ' 17.

41 threaded stem interconnection 42 abutment seal 43 threaded stub interconnection 44 abutment seal 45 nozzle 46 abutment (end seal) 47 locating ring / pins 51 perforated (disk) screen 71 breather tube / conduit 72 mounting ferrule 73 discharge outlet secondary (poppet) valve 81 valve body 82 valve plate 83 valve stem 84 valve spring (adjustable) stop head 86 breather pipe 87 mounting screw 88 ferrule 89 end carrier spider 91 valve seal 101 bonding 113 valve stem 120 secondary valve 121 valve body 122 nozzle end 123 valve stem support 124 valve housing 125 support leg 126 passageway 127 passageway valve member 131 valve foot 132 valve spring 133 valve head 134 inner foot surface 2 ': 1

Claims (6)

1. Claims A flow delivery and discharge control, comprising a primary valve

   (28), and a secondary valve (10), operative as a downstream spillage inhibitor, by residual discharge containment.
2. 2.

   A secondary valve (10), for fitment in a flow discharge nozzle spout (25), to operate in conjunction with a primary flow regulatory or control valve (28).
3. A (fluid) delivery spillage inhibitor, for a discharge spout (25) of a delivery nozzle, comprising a valve (10), with a valve member (12), biassed into a closed condition, [against a delivery flow direction], operative to open under flow pressure and to close automatically upon flow pressure reduction, and entrap residue within the nozzle spout (25), ready for discharge in a subsequent delivery cycle, whereby to inhibit inadvertent spillage from the nozzle at the end of a delivery cycle.
4. 4.

   A spillage or dribble inhibitor, substantially as hereinbefore described, with reference to, and as show in, the accompanying drawings.
5. 5.

   A delivery system incorporating a spillage inhibitor valve as claimed in any of the preceding claims. .
6. 6. ... :, A flow delivery system incorporating a spillage inhibitor deployable after a shut-off valve.

   A flow delivery system configured to inhibit residual fluid retention after a shut-off valve. 8.

   A valve configured to inhibit residual fluid retention after shut-off. r

   À À; 1 c :: . 1 . .