Dispensing means

Information

  • Patent Grant
  • 6446834
  • Patent Number
    6,446,834
  • Date Filed
    Wednesday, December 13, 2000
    24 years ago
  • Date Issued
    Tuesday, September 10, 2002
    22 years ago
Abstract
A beverage dispense apparatus having one or more outlets for fluids to be dispensed, a fluid supply line for each fluid, each outlet being governed by a valve, and a valve actuator to open and close each valve. A flow sensor is positioned in each fluid supply line and connected to a control which controls the opening of its respective valve on receiving a start signal and actuates closing of the valve when the pre-determined amount of fluid flow has been achieved. Each valve includes a closure member movable in a passageway from a first position in which the valve is fully closed to a second position in which the valve is fully open. The closure member comprises a groove having a transverse cross section that increases in area in the downstream or upstream direction, whereby movement of the closure member from the first position towards the second position opens a flow channel through the groove.
Description




This invention relates to dispensing means, particularly, but not exclusively, for beverages made by mixing beverage constituents. It has particular application in the field of soft drinks such as colas or flavoured sodas but it will be appreciated that it is not limited thereto.




Beverages may be dispensed, for example, using a dispense tower which is raised above a serving table level to provide beverage outlets through dispense valves located at or about shoulder height. The tower contains pipework for carrying the beverage ingredients and its outer surface frequently carries advertising material for the beverage(s) to be dispensed.




The tower may have multiple outlets at its upper end, the outlets forming a horizontal line of dispense valves. This permits more than one beverage to be dispensed simultaneously and it is possible to have a number of different beverages dispensable from a single tower.




In the case of beverages such as colas, the tower may carry pipework for chilled soda (carbonated water) and for a cola or other flavoured syrup. The separately supplied soda and syrup are then mixed together in the correct proportions at the outlet in a specially-designed dispense valve known as a post-mix dispense valve. A still water supply may also be required so that still beverages can be mixed and dispensed.




The present invention is applicable to such an arrangement but, again, is not limited thereto. Thus the apparatus of the invention may be applied to a series of separate dispense heads or to a single all-embracing dispense head.




The present invention aims to provide an improved mixing and dispensing means whereby the amount of each fluid to be dispensed can be accurately controlled.




Accordingly, the invention provides a beverage dispense apparatus comprising a dispense head having one or more outlets for fluids to be dispensed, a fluid supply line to the head for each fluid, each outlet being governed by a valve, a valve actuation means to open and close each valve, a flow sensor positioned in each fluid supply line and connected to a control means which controls the valve actuation means whereby it actuates opening of its respective valve on receiving a start signal and actuates closing of the valve when the pre-determined amount of fluid flow has been achieved, the valve of each outlet comprising a housing containing a passageway between an inlet and an outlet of the valve, a closure member movable in the passageway from a first position in which the valve is fully closed to a second position in which the valve is fully open, the closure member engaging the wall of the passageway to seal the passageway, the wall of the passageway and/or the closure member defining at least one groove, the groove having a transverse cross section that increases in area in the downstream or upstream direction, whereby movement of the closure member from the first position towards the second position opens a flow channel through the groove.




A start signal may conveniently be given by pressing an appropriately marked button on the dispense head for the desired beverage from the range of beverage options offered by the apparatus. The start signal activates the control means, which may conveniently be electronic.




Alternatively, each beverage option may have a code which is keyed into the apparatus to give the appropriate start signal.




The flow sensor may be of any convenient type. Thus, for example, it may be an ultra-sonic sensor or a flow sensing turbine of the types well-known in the art.




The valve actuation means may be, for example, a stepper motor, e.g. of the pulsed, magnetically driven type, a proportional solenoid actuator or the like. Alternatively the actuation means may be hydraulic, or pneumatic or any suitable combination e.g. electromechanical.




Thus the valves can be controlled to govern the proportions of fluids that are fed to and mixed at the head prior to dispense. Alternatively they can be controlled to provide a predetermined volume of a single fluid.




In addition to blending beverage constituents, e.g. to provide lower or higher carbonated colas, the apparatus may be used to blend warm and cold fluids together by the incorporation of a temperature sensor to give a mixed beverage of predetermined temperature.




As indicated above, the valves have a groove construction, i.e. the valve closure member and the wall of the passageway containing the valve closure member define between them one or more grooves, e.g. a pair of diametrically opposed grooves, the grooves extending and increasing or decreasing in cross-sectional area along the axial length of the passageway, whereby opening and closing of the valve exposes more or less of the groove volume to increase/decrease the volume of the passageway through the valve. The grooves may, for example, increase in cross-sectional area in the downstream direction.




The grooves may be of a “V” cross-section but other shapes, e.g. circular or rectangular cross-section may be utilised, if desired. For convenience, however, the grooves will hereafter be referred to as V-grooves.




The grooves may, for example, be cut or moulded into the material of the passageway wall or closure member by conventional means depending on the material used..




The grooves are preferably V-grooves that widen along their length at an angle of from 1° to 20°.




Where more than one groove is provided in the passageway, it is not essential that all the grooves are positioned to commence and finish at the same distance along the passageway.




The valve closure member may carry one or more sealing rings to engage the wall of the passageway in the first position, i.e. the closure member may engage the wall of the passageway by means of the sealing ring(s) to close the outlet or, alternatively, the closure member and passageway may be a precision fit in the first position to close the outlet without a seal.




As indicted above, depending on the desired particular construction, the V groove or grooves in the passageway may increase in cross-sectional area in the upstream or downstream direction. In the latter case, the valves have the added advantage of having greater self-cleaning properties, i.e. larger particles can pass more readily through the valve in the open position without causing partial blockage than for a conventional valve having an annular passageway of the same throughput.




Conveniently the passageway and closure member are of generally cylindrical transverse cross-section and a pair of grooves may be opposed diametrically across the passageway. However, it will be appreciated that the invention is not limited to such constructions.




The progressive increase or decrease in area of the V-groove flow channels can provide excellent linear flow through the valves.




Where the flow sensor is of the ultra-sonic type it may be of a construction generally known per se. Essentially, such a sensor comprises a piezo-electric crystal member which emits ultra-sonic pulses when an electrical signal is applied to it. The member can also receive ultrasonic pulses and produce an electrical output signal therefrom. A sensor is positioned at each end of a flow passage for the fluid and an ultra-sonic pulse is passed through the fluid from the upstream to the downstream sensor and then a pulse is passed through the fluid from the downstream sensor to the upstream sensor. Thus the signals are measured in two directions through the flowing fluid and the thus monitored flow is signalled to the electronic control unit. It will be appreciated that the signal flight time may vary with fluid density, viscosity and temperature and the control unit will be pre-programmed accordingly.




The piezo-electric sensors may conveniently each be designed as a unit to plug into a suitable housing in the wall at each end of the flow passage whereby they can pulse through the wall. Thus the sensor units may be removed without breaching the passageway.




Moreover, the flow passage may be angled e.g. may be L-shaped, with a reflector at the corner of the angled passage to reflect the ultrasonic signals around the bend of the angle. The angle may be, for example, about 90° but other angles may be utilised as convenient. This angling of the passage enables the sensor unit to be packaged into a smaller volume.











Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which:





FIG. 1

is a diagrammatic representation of one form of apparatus according to the invention;





FIG. 2

is a representation in side view and part section of a dispense head for use in the invention;





FIG. 3

is a view in the direction of arrow A of

FIG. 2

;





FIG. 4

is a diagrammatic illustration in part section of a first valve for use in the invention;





FIG. 5

is a similar illustration of a second valve for use in the invention;





FIG. 6

is a similar view of a third valve for use in the invention;





FIG. 7

is a similar view of a fourth valve for use in the invention;





FIG. 8

is a similar view of a fifth valve for use in the invention;





FIG. 9

is a view in the direction of arrow A of

FIG. 8

;





FIG. 10

is a perspective view of one form of ultra-sonic sensor suitable for use in the invention; and





FIG. 11

is a section on line XI—XI of the sensor of FIG.


10


.











In

FIG. 1

a dispense head


10


contains two control valves (not shown) to allow flow through outlet


11


of the head when a drink is dispensed into a cup


12


. Each valve is actuated by a stepper motor


13


,


14


respectively and the stepper motors are connected to and controlled by pre-programmed electronic control unit


15


.




Two flow lines


16


,


17


for different fluids are provided, flow being to the head


10


. Each flow line


16


,


17


passes through an ultra-sonic flow sensor


18


,


19


respectively. Each sensor


18


,


19


is connected to control unit


15


whereby the flow through each line


16


,


17


is monitored.




On initiating the start signal, e.g. a button (not shown) on head


10


, the control unit causes motors


13


,


14


to open the valves and fluids e.g. carbonated water and a syrup respectively, flow through lines


16


and


17


to the head


10


. The rate of flow in each line is monitored by sensors


18


,


19


and when a pre-determined amount of each fluid has passed through the sensors the control unit actuates valves


13


and


14


to shut off flow. The fluids are mixed in head


10


and dispensed into cup


12


.




Alternatively the start signal may activate flow in one only of the flow lines whereby a predetermined amount of a single fluid, e.g. carbonated or still water, is dispensed.




In

FIGS. 2 and 3

is shown a specific form of a head of the apparatus of the invention.




Head


20


again contains two control valves, one of which, valve


21


is shown. Each valve has a flow passageway defined by a pair of V-grooves


22


,


23


in the passageway wall, the grooves being opposed diametrically across the passageway and tapering in the direction of flow which leads to an outlet


24


.




The valves are actuated by a pair of stepper motors


25


,


26


, motor


25


actuating valve


21


and motor


26


actuating the unseen valve.




Two fluid passageways


27


,


28


are provided, e.g. for carbonated and still water respectively, in a mounting block


29


for coupling to a source of the fluids. Within the head


20


passageways


27


and


28


lead to narrower drilled passages


30


,


31


respectively. Each passage


30


,


31


leads to an ultrasonic flow sensor, only one of which, sensor


32


, is visible in FIG.


2


.




Flow sensor


32


and the unseen sensor are L-shaped in construction for ease of fitment into head


20


. However, it will be appreciated that they may, if desired, be linear and they may, if convenient, be fitted into their respective flow lines outside of the head.




The sensors and the stepper motors are connected to a pre-programmed electronic control unit (not shown) in the manner shown in

FIG. 1

whereby actuation of the valves and flow of the fluids is controlled in a pre-determined manner.




Again, on actuating the start signal, one or the other valve is opened to dispense the chosen fluid or both valves may be opened to dispense a mixture of the fluids until the predetermined volume has been dispensed when the valve (or valves) is (are) closed.




Alternative valve arrangements will now be described with reference to

FIGS. 4

to


9


.




In

FIG. 4

, a valve


110


comprises a closure member in the form of a piston


111


in a passageway


112


leading from an inlet


113


to an outlet


114


, the outlet extending at right angles to passageway


112


. Fluid flow is in the direction of the arrows A and B (which direction will be similarly indicated in all the embodiments below.).




Wall


115


of the passageway


112


A adjacent inlet


113


is of cylindrical cross-section but with a pair of grooves


116


,


117


diametrically opposed across the passageway. The grooves are of generally V configuration and increase in cross-sectional area as they extend in the downstream direction. A narrower extension


118


of piston


111


is a close sliding fit in passageway


112


A.




At its downstream end piston


111


carries a sealing ring


119


in an annular groove


120


. Downstream of groove


120


piston


111


tapers to a narrower extension


121


which slides in a narrow extension


112


B of passageway


112


and engages a sealing ring


122


in the wall of passageway


112


B.




The wall of passageway


112


has a tapered section


123


leading to its narrower extension


112


B and seal


119


of piston


111


engages section


123


to close outlet


114


which is downstream thereof.




Piston


111


is moved backwards and forwards in passageway


112


to open and close the valve by means of its extension


121


being attached to a stepper motor (not shown) or other suitable means. This movement is indicated by arrows C—C.




The V grooves enable precise control of fluid flow with the flow control band width being indicted between arrows D—D. It has a self-cleaning flow path through the increasing groove cross-section and is pressure closed, although spring-assistance may be provided, if desired.




It will be noted that the upstream end of extension


118


of piston


111


will be in the maximum flow position of the V grooves at the moment that seal


119


engages wall portion


123


and closes the outlet.




In

FIG. 5

valve closure member


130


is a cylindrical piston rod moveable backwards and forwards as indicated by arrows C—C in a passageway


131


between an inlet


132


and an outlet


133


. Piston


130


is of constant diameter along its length and has an annular groove


134


containing a sealing ring


135


adjacent its downstream end.




Passageway


131


at inlet end


132


is of greater diameter than piston


130


and narrows via a stepped wall portion


136


to a narrower portion


131


A in which piston


130


is a sliding fit and against the wall of which seal


135


seals in the closed position. A pair of diametrically opposed V grooves


137


,


138


are provided in the wall defining narrower passage portion


131


A, the grooves commencing at stepped wall portion


136


and narrowing in the downstream direction.




The upstream end of piston


130


is attached to a stepper motor (not shown) or other means to move the piston to open and close the valve.




The valve provides a gradual increase/decrease in pressure/flow on opening and closing. This construction provides minimal pressure on the seal in the closed position and low torque on the, e.g., stepper motor. There is no end stop load on the motor on closing the valve.




In

FIG. 6

, the valve closure member is a piston rod


140


of cylindrical configuration movable backwards and forwards as indicated by arrows C—C in a passageway


141


between an inlet


142


and an outlet


143


. Piston


140


tapers to a narrower nose


140


A at its downstream end and nose


140


A itself tapers at its downstream end to a flat end surface


144


. The tapering portion


145


of the nose leading to the end surface


144


provides the sealing means to close the outlet as is described below.




As with the valve of

FIG. 5

, passageway


141


at its inlet end is of greater diameter than piston


140


and narrows via a stepped wall portion


146


to a narrow portion


141


A in which piston


140


is a sliding fit. A pair of diametrically-opposed V grooves


147


,


148


are provided in the wall defining narrower passage portion


141


A, the grooves commencing at stepped wall portion


146


and narrowing in the downstream direction.




The upstream end of piston


140


is attached to a stepper motor (not shown) or other means to move the piston to open and close the valve, opening of the valve allowing flow through grooves


147


and


148


.




Passageway portion


141


A narrows at its downstream end by means of a tapered wall portion


149


and leads thereby to narrower outlet


143


. Tapered wall portion


149


and tapered portion


145


of the nose of piston


140


are a mating, close tolerance fit in the closed position of the valve, whereby the outlet is closed without need for a separate sealing ring.




Thus this construction has no sealing ring to wear and provides a gradual increase/decrease of pressure/flow on opening and closing of the valve.




In

FIG. 7

is illustrated another valve that does not require a separate sealing ring. The valve closure member is a cylindrical piston


150


movable backwards and forwards as indicated by arrows C—C in a passageway


151


between an inlet


152


and an outlet


153


.




Again passageway


151


at its inlet end is of greater diameter than piston


150


and narrows via a stepped wall portion


156


to a narrower portion


151


A in which piston


150


is a sealing fit. Thus piston


150


is a precision fit into a bore of passageway portion


151


A.




A pair of diametrically opposed V grooves


157


,


158


is provided in the wall defining narrower passage portion


151


A, the grooves again commencing at stepped wall portion


156


and narrowing in the downstream direction.




Again, the upstream end of piston


150


is attached to a stepper motor (not shown) or other means to move the piston to open and close the valve, opening of the valve allowing flow through grooves


157


and


158


.




As with the

FIG. 6

construction, this valve may be “seal-less”. It also provides a gradual increase/decrease of pressure/flow on opening and closing, puts minimal pressure on the sealing surfaces when closed and low torque on the motor and has no end stop loading on the motor.




In

FIG. 8

, the closure member is a cylindrical piston


160


movable backwards and forwards (in the direction C—C) in a passageway


161


between an inlet


162


and an outlet


163


which leads off at right angles from passageway


161


partway along the length of the piston.




The wall defining passageway


161


has a pair of diametrically-opposed V grooves


167


,


168


between the inlet and an annular chamber


164


from which outlet


163


leads off. The grooves widen in the downstream direction to be at their widest as they reach chamber


164


, which chamber forms part of and lies centrally of passageway


161


.




The walls of passageway


161


define a pair of annular recesses


165


,


166


, each recess carrying a sealing ring


169


,


170


, respectively.




Recess


165


and its sealing ring


169


lie at the upstream end of V section grooves


167


,


168


, and piston


160


seals against ring


169


in the valve closed position. The seal


169


and the grooves


167


and


168


are so positioned that the upstream end of each V groove commences just downstream of the seal to prevent hydraulic lock occurring on the valve closing. As can be seen in

FIG. 9

, from which the seal


169


has been removed for clarity, the upstream ends


167


A,


168


A of grooves


167


and


168


just extend to breakthrough the downstream wall


165


A of recess


165


.




Recess


166


and its sealing ring


170


are positioned in passageway


161


beyond chamber


164


and outlet


163


and the piston


160


is a sliding sealing fit in ring


170


as it moves to open and close the valve.




Again, this construction provides gradual opening and closing of the valve, the sealing rings are subjected to little wear and the V grooves are self-cleaning in the flow direction shown.




All the above valves of

FIGS. 4

to


9


provide a combined flow control and cut off means in a small compact unit.




The flow direction may, if desired be reversed in each of the above five valve embodiments but it will be appreciated that the improved self-cleaning effect will be achieved only where the V grooves broaden in the direction of flow.




In

FIG. 10

is shown in more detail an ultra-sonic flow sensor arrangement for use in the invention.




In

FIGS. 10 and 11

a sensor


200


comprises an elongated moulded plastics housing


201


having an inlet end


202


and an outlet end


203


with a V-shaped intermediate portion


204


between the inlet end and the outlet end. (It will be appreciated that fluid flow may be in either direction through the housing so that inlet .


202


may become the outlet and outlet


203


may become the inlet.).




A through passageway for fluid extends from inlet end


202


to outlet end


203


and comprises a longitudinally-extending inlet passageway portion


205


, a V-shaped intermediate passageway portion


206


, having arms


206


A,


206


B and a longitudinally-extending outlet passageway portion


207


. As shown, the inlet and outlet passageway portions


205


,


207


are stepped so that each passageway narrows from the outside of the housing to the intermediate passageway portion


206


. The apex


208


of the V-shaped passageway portion


206


is at the base of the housing


201


and is defined by a hole in the base of the housing, the hole being closed by a reflector plate


209


. Plate


209


, which may be of stainless steel, is screwed to the base of the housing


201


by screws (not shown) and is sealed to the base of the housing


201


around the hole in the base by a suitable gasket


210


.




At the upper end of each arm


206


A,


206


B is wall


211


A,


211


B of the housing. On the opposite side of each wall


211


A,


211


B is a recess


212


A,


212


B in the exterior surface of the housing. Each recess


212


A,


212


B can contain a piezo-electric crystal sensor unit


213


A,


213


B respectively. Each unit


213


A,


213


B is held in place in its recess by a clamping plate


214


A,


214


B respectively and each clamping plate can be screwed to the housing


201


via screw holes


215


A,


215


B respectively. One screw


215


C is shown in hole


215


B. A suitable packing compound (not shown) may be placed in the recesses


212


A,


212


B prior to fitting units


213


A,


213


B therein to ensure the units are held in place without voids between them and their respective walls


211


A,


211


B. Electrical contact to the sensor units is made via electrical sockets


216


A, through the clamping plate


214


A and similarly, but not shown, through plate


214


B.




When the piezo-electric sensor units are activated as fluid flows through the housing, their ultra-sonic pulses pass through wall


211


A or


211


B and then through the fluid along passageway portion


206


A or


206


B, strike reflector plate


209


and are reflected along passageway portion


206


A or


206


B to be received by the other sensor unit. Thus when sensor


200


is used in an apparatus as described, for example, with reference to

FIGS. 1

to


3


above, the pulses are timed in two directions, with and against the flow, and the thus monitored flow is signalled to a control unit.




The V-shaped central portion of the through passageway enables the sensor housing to be reduced in overall size so that it can be more readily packaged into a beverage dispense system.




Moreover, as the piezo-electric crystal units are separated from the fluid flow passageways by walls


211


A,


211


B, the sensor units do not come into direct contact with the fluid. Hence the sensor units


213


A,


213


B can be removed for replacement or repair without breaching the fluid passageway and, hence, it is not necessary to close down or depressurise the fluid system for this purpose.




The invention enables very accurately metered beverages to be dispensed at the correct rate and in correct proportions. It can equally be used for portion control or free flow dispense.



Claims
  • 1. A dispense apparatus for dispensing there from a diluent liquid and a concentrate liquid a desired ratio, comprising:a dispense valve body having a diluent inlet and a diluent outlet and a fluid passageway there between and a concentrate inlet and a concentrate outlet and a fluid passageway there between so that diluent and concentrate flow in a downstream direction from their respective inlets to their respective outlets, a v-groove regulator in each passageway having a central orifice, the central orifice having sidewalls and the sidewalls each having at least one tapered groove therein and each groove increasing in cross-sectional area in a direction opposite to the of flow of diluent or concentrate there through, a first rod extending through the v-groove regulator in the diluent passageway and having a rod end moveable by a first linear actuator to a fully extended closed position and a fully retracted open position and to a plurality of positions there between for regulating the cross-sectional area of the one or more tapered grooves through which the diluent can flow for regulating the flow rate thereof, a second rod extending through the v-groove regulator in the concentrate passageway and having a rod end moveable by a first linear actuator to a fully extended closed position and a fully retracted open position and to a plurality of positions there between for regulating the cross-sectional area of the one or more tapered grooves through which the concentrate can flow for regulating the flow rate thereof, a diluent flow rate sensing means for sensing the flow rate of the diluent and a concentrate flow rate sensing means for sensing the flow rate of the concentrate and both flow rate sensing means connected to a control means for inputting thereto flow sensing data, and the control means for controlling the operation of the first and second linear actuators for regulating the flow of the diluent and concentrate in response to the input flow sensing data.
  • 2. The apparatus as defined in claim 1, and each flow sensor comprising an ultrasonic sensor.
  • 3. The apparatus as defined in claim 1, and each flow sensor comprising a pair of piezo-electric signal generating sensors units one of each pair placed in an upstream position in each of the fluid passageways and the other of the pair in a downstream position of each fluid passageway whereby separate ultrasonic pulses can be passed through the diluent fluid and through the concentrate fluid in one direction and then in a direction opposite thereto, and the piezo-electric sensor pairs connected to the control for inputting data thereto relative to time required for each pulse to travel between the sensor pairs so that the control can calculate the flow rate of the diluent and concentrate fluids.
  • 4. A dispense apparatus for dispensing there from a diluent liquid and a concentrate liquid a desired ratio, comprising:a dispense valve body having a diluent inlet and a diluent outlet and a fluid passageway there between and a concentrate inlet and a concentrate outlet and a fluid passageway there between so that diluent and concentrate flow from their respective inlets in a downstream to their respective outlets, a v-groove regulator in each passageway having a central orifice, the central orifice having sidewalls and the sidewalls each having at least one tapered groove therein and each groove decreasing in cross-sectional area in a direction opposite to the of flow of diluent or concentrate there through, a first rod extending through the v-groove regulator in the diluent passageway and having a rod end moveable by a first linear actuator to a fully extended closed position and a fully retracted open position and to a plurality of positions there between for regulating the cross-sectional area of the one or more tapered grooves through which the diluent can flow for regulating the flow rate thereof, a second rod extending through the v-groove regulator in the concentrate passageway and having a rod end moveable by a first linear actuator to a fully extended closed position and a fully retracted open position and to a plurality of positions there between for regulating the cross-sectional area of the one or more tapered grooves through which the concentrate can flow for regulating the flow rate thereof, a diluent flow rate sensing means for sensing the flow rate of the diluent and a concentrate flow rate sensing means for sensing the flow rate of the concentrate and both flow rate sensing means connected to a control means for inputting thereto flow sensing data, and the control means for controlling the operation of the first and second linear actuators for regulating the flow of the diluent and concentrate in response to the input flow sensing data.
  • 5. The apparatus as defined in claim 4, and each flow sensor comprising an ultrasonic sensor.
  • 6. The apparatus as defined in claim 4, and each flow sensor comprising a pair of piezo-electric signal generating sensors units one of each pair placed in an upstream position in each of the fluid passageways and the other of the pair in a downstream position of each fluid passageway whereby separate ultrasonic pulses can be passed through the diluent fluid and through the concentrate fluid in one direction and then in a direction opposite thereto, and the piezo-electric sensor pairs connected to the control for inputting data thereto relative to time required for each pulse to travel between the sensor pairs so that the control can calculate the flow rate of the diluent and concentrate fluids.
Priority Claims (1)
Number Date Country Kind
9813192 Jun 1998 GB
Parent Case Info

This application is a continuation of PCT/GB99/01909, filed Jun. 15, 1999.

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Continuations (1)
Number Date Country
Parent PCT/GB99/01909 Jun 1999 US
Child 09/739021 US