Watercraft fuel supply apparatus and method

Abstract
A fuel storage and supply apparatus (22) for a watercraft (10) incorporating a plurality of connections (50,66) penetrating a housing (32) in a single opening in a fuel tank (12). Each connection is sealed by a radial O-ring (56,68) so that the connection may be rotated about a longitudinal axis without adversely affecting the seal. A single opening (34) in the tank may thereby be used to provide connections for a fill tube (66), fuel tube (50), vent (86), and electrical penetrations (150) for an in-tank pump (136) or level sensor (156).
Description




BACKGROUND OF THE INVENTION




The present invention relates generally to fuel supply systems, and more particularly to a fuel supply system for a watercraft, and in particular, to a fuel tank having a plurality of sealed, rotatable connections formed through a single opening in the tank.




Present marine fuel storage and distribution systems typically include a fuel tank, a fuel conduit connected between an engine and the fuel tank, a pump for conveying fuel through the conduit, a priming pump, one or more filters for removing sediment and water from the fuel prior to its delivery to the engine, fill and vent tubes connected to the tank, a cap for the fill tube that may provide the venting function when installed, and instrumentation for providing a signal corresponding to the level of fuel within the tank. One or more of these components may be duplicated in watercraft having more than one engine, or for the purpose of improved capacity, flexibility or reliability.




It is known that each joint or connection in a fuel system is a point for potential leakage of liquid fuel and/or vapors. It is therefore desirable to minimize the number of connections within a fuel system. In particular, it is desirable to minimize the number of connection to a fuel tank, since the tank is an expensive component to fabricate and is often installed in a location that is not accessible for repair activities. Furthermore, since the tank provides the primary boundary for the containment of the fuel, it is desirable to make the tank as fail-safe as possible.




It is also known that the space requirements and layout of a fuel system are important parameters in the design of a watercraft. The location, number and capacity of fuel tanks and the layout of fuel and vent lines may not be known until the power unit(s) for the boat are selected. Accessibility for routine maintenance and servicing must also be considered when designing a marine craft fuel system.




BRIEF SUMMARY OF THE INVENTION




Thus there is a particular need for a fuel system for a watercraft that provides a high degree of flexibility for the marine designer. Such a fuel system should minimize the number of connections, and in particular, should minimize the number of penetrations into the fuel tank.




Accordingly, a fuel storage and supply apparatus for a watercraft is described herein as including: a fuel tank having an opening formed therein; a housing sealingly attached to the fuel tank within the opening, the housing having an opening formed therethrough; a tube disposed through the housing opening and longitudinally rotatable therewithin; and a radial O-ring seal disposed between a wall of the opening and an outside surface of the tube.




The tube of the watercraft fuel storage and supply apparatus is further described as including: a groove formed in the outside diameter surface of the tube for receiving and retaining the radial O-ring seal; a flange formed on the outside surface of the tube, the flange having a diameter greater than the diameter of the housing opening and having a bottom surface disposed against a top surface of the housing; and a clamping plate removably attached to the housing and covering at least a portion of the flange for retaining the tube within the housing opening.




The watercraft fuel storage and supply apparatus may further include: a valve cavity formed within the housing and in fluid communication between the interior and exterior of the tank; a check valve disposed within the valve cavity; a fuel outlet nozzle rotatably disposed within the valve cavity; and a radial O-ring seal disposed between the fuel outlet nozzle and a wall of the valve cavity. The check valve may include: a plate disposed within the valve cavity and sealed thereto about its perimeter; a hole formed in the plate for the passage of fuel therethrough; and an elastomer attached to the plate and extending therefrom to cover the hole, the elastomer operable to bend to permit fuel to pass out of the tank through the hole, and operable to seal the hole in the event of the flow of fuel into the tank.











BRIEF DESCRIPTION OF THE DRAWINGS




The features and advantages of the present invention will become apparent from the following detailed description of the invention when read with the accompanying drawings in which:





FIG. 1

is a schematic illustration of a boat having a motor and a fuel storage and supply apparatus.





FIG. 2

is a partial section view of a portion of the fuel tank of

FIG. 1

illustrating the single opening in the tank and rotatable fuel fill and delivery tubes sealed with radial O-ring seals installed into a housing in the opening.





FIG. 3

is a partial sectional view of an anti-siphon check valve built into a rotatable fuel fill tube sealed with a radial O-ring in a housing in the opening of a fuel tank.





FIG. 4

is a partial section view of a fuel tank having a single opening and an in-tank fuel pump and filter. The fuel outlet of the pump is directed to a rotatable fuel tube sealed with a radial O-ring seal into a housing in the opening. The housing also includes an electrical penetration operable to deliver electrical energy to the pump motor.





FIG. 5

is a partial section view of a fuel tank having a single opening and an in-tank fuel level sensor. Electrical connections to the sensor are made via an electrical penetration mounted to a housing in the opening. The housing also supports a rotatable fuel outlet tube sealed to the housing by a radial O-ring seal.











Similar structures illustrated in multiple figures may be designated by the same numeral in multiple figures.




DETAILED DESCRIPTION OF THE INVENTION





FIG. 1

illustrates a watercraft


10


having an internal combustion engine


11


mounted in the interior of a boat hull


14


. A power unit drive train


16


extends through the transom


18


of the watercraft


10


to deliver power to a propeller


20


. This illustration can be recognized as representing the inboard/outboard style pleasure craft common in the watercraft industry, but one may appreciate that the apparatus described herein may be applied to any style of marine propulsion system, including inboard and outboard units. A fuel storage and supply apparatus


22


provides fuel (not shown) to engine


11


. The fuel storage and supply apparatus


22


includes a tank


24


, fuel supply lines


26


, a fuel fill tube


28


, and a fill tube cap


30


. The fuel lines


26


and fuel fill tube


28


are supported in a housing


32


mounted in a single opening


34


formed in a tank


24


.





FIG. 2

is a more detailed illustration of a portion of the fuel storage and supply apparatus


22


of FIG.


1


. Housing


32


can be seen disposed within the single opening


34


of tank


12


. Housing


32


is illustrated as being threaded into an adapter


36


which, in turn, is fixedly attached to tank


12


within opening


34


. In one embodiment, tank


12


is formed by a blow molding process, wherein opening


34


is formed at the location of the blow pin used during the molding process. Adapter


36


includes precision dimensioned threads


38


formed along its inside diameter, and a flange surface


40


adapted to span the somewhat irregularly shaped opening


34


. Adapter


36


may be sealed to tank


12


by any process known in the art, such as by welding for the embodiment of a polyethylene blow molded tank


12


. Adapter


36


has formed on its exterior perimeter a series of threads


42


formed to mate with threads


38


of adapter


36


. Housing


32


may thereby be screwed into adapter


36


until its flange


44


abuts the upper surface of adapter flange


40


. A seal or gasket


46


may be disposed between the mating surfaces of adapter


36


and housing


32


. In this manner, housing


32


is sealingly and removably attached to the fuel tank


12


within the opening


34


.




Housing


32


may be formed to include any number of penetrations into the interior of tank


12


. In the embodiment illustrated in

FIG. 2

, housing


32


functions to support both fuel line


26


and fill tube


28


. Housing


32


includes an opening


48


formed therethrough for the passage of fuel tube


50


. The outlet


52


of fuel tube


50


is attached to fuel line


26


by any attachment scheme known in the art. An inlet end


54


of fuel tube


50


extends into the interior of tank


12


for attachment to a fuel tube extension (not shown) operable to draw fuel from proximate the bottom of tank


12


. Fuel tube


50


is sealed to housing


32


by a radial O-ring seal


56


. O-ring


56


may be any material known in the art to be functional in such an application, such as a rubber or fluorocarbon material. O-ring


56


is retained in position around the exterior of fuel tube


50


by being partially disposed within a groove


58


formed in the exterior surface of fuel tube


50


. The dimensions of the exterior of fuel tube


50


, the interior of opening


48


, and O-ring


56


are selected such that the O-ring provides an appropriate pressure seal against the leakage of fuel through the opening


48


around the exterior of fuel tube


50


. In most applications, the differential pressure across O-ring seal


56


will be no more than 10-15 psi, which is well within the design pressures of known radial O-ring seal designs. Advantageously, O-ring seal


56


permits fuel tube


50


to be rotated about its longitudinal axis within opening


48


without any degradation of the sealing function, thereby allowing the outlet


52


to be directed to any radial position. To restrain fuel tube


50


from vertical movement out of opening


48


, a locking plate


60


is secured by a fastener


62


to the housing


32


in order to restrain the vertical movement of flange


64


formed on the outside surface of fuel tube


50


.




Fill tube


66


is supported in housing


32


in a manner very similar to that of fuel tube


50


. A plurality of grooves


68


are formed on the outside diameter surface of tube


66


for receiving and retaining a plurality of parallel radial O-rings


70


. A flange


72


is formed on the outside diameter surface of tube


66


to have a diameter greater than the diameter of the opening


74


in which tube


66


is disposed. A bottom surface of flange


72


is held against a top surface


76


of housing


32


by clamping plate


78


. Clamping plate


78


is, in turn, held in position by fastener


80


threaded into the body of housing


32


. Clamping plate


78


covers at least a portion of flange


72


for removably retaining the tube


66


within the opening


74


of housing


32


. Fill tube


66


may be rotated about it longitudinal axis to position its outlet


82


in any of a plurality of radial positions without affecting the functionality of the radial O-ring seal


70


.





FIG. 3

is a partial sectional illustration of an embodiment wherein both a fuel supply tube


84


and a vent tube


86


are rotatably mounted within a housing


88


which, in turn, is rotatably sealed within an opening


90


formed in the tank


12


. Radial O-ring


92


is disposed within a notch


94


formed in an exterior surface of housing


88


to provide the pressure seal against tank opening


90


. Cover plate


96


prevents the vertical movement of housing


88


and is removably attached to tank


12


by fasteners


98


. Vent tube


86


is rotatably sealed by O-ring


100


within vent opening


102


formed in housing


88


. Fuel supply tube


84


is rotatably sealed within fuel supply opening


104


by radial O-ring


106


. An anti-siphon check valve assembly


108


is formed to be integral to the housing


88


. A valve chamber


110


is formed in housing


88


and is in fluid communication with the fuel supply tube


84


and fuel inlet


112


. Check valve assembly


108


is disposed within the valve cavity


110


and includes a plate


112


sealed to housing


88


about its perimeter by gasket


114


. A plurality of holes


116


are formed in plate


112


to permit the passage of fuel from inlet


113


to fuel tube outlet


118


. An elastomeric disk


120


is attached to the plate


112


, such as by extending tang


122


through an opening


124


of plate


112


. Elastomeric disk


120


extends from the point of attachment to cover holes


116


along the upper surface of plate


112


. In this manner, elastomeric disk


120


is operable to bend upward to permit the flow of fuel out of tank


12


through inlet


112


and valve cavity


110


to outlet


118


of fuel tube


84


. However, in the event of any reverse flow through fuel tube


84


, elastomeric disk


120


is operable to be forced downward against the tope of plate


112


, thereby covering holes


116


and terminating any such reverse flow. Elastomeric disk


120


may be any material known in the art and suitable for such an application, such as for example, rubber. Other styles of valves may be used, such as a spring loaded poppet valve having a predetermined opening pressure. Housing


88


and tubes


84


,


86


may be manufactured from any material compatible with the fuel to be used, and may preferably be a machinable plastic or injection molded material. As with previous embodiments, fuel supply tube


84


and vent tube


86


may be rotated about their respective longitudinal axes to position their respective outlets to any radial position without affecting the sealing function provided by O-rings


100


,


106


. Furthermore, the entire housing


88


may be rotated about a longitudinal axis without affecting the sealing function provided by O-ring


92


.





FIG. 4

is a partial cross-sectional illustration of another embodiment of a fuel tank


12


having an opening


126


formed therein, with a housing


128


disposed within opening


126


and containing a plurality of openings


130


,


132


for the installation of various components of the fuel storage and supply apparatus. A fuel tube assembly


134


may be rotatably installed within opening


132


in a manner similar to that described above. In this embodiment, a one-piece fuel pump assembly


136


including a pump and a motor apparatus is disposed within the interior of the tank


12


proximate the bottom


138


of the tank


12


. A fuel line


140


is connected between an outlet of pump


136


and fuel tube assembly


134


. A replaceable fuel filter


142


is disposed within a fuel filter housing


144


attached at the inlet of pump


136


. In an alternate embodiment wherein no fuel pump and motor apparatus is installed within the tank


12


, the fuel filter


142


and housing


144


may be installed directly to the fuel line


140


. Electricity for pump


136


is provided via electrical lines


146


connected to the pins


148


of an electrical penetration assembly


150


disposed within opening


130


of housing


128


. Electrical penetration assembly


150


is rotatably sealed within opening


130


by radial O-ring seal


152


. It may be appreciated that the pump/motor


136


and filter assembly


144


may be preassembled onto housing


128


prior to its installation within opening


126


of tank


12


. The replacement of filter


142


may then be simply accomplished by the removal of cover plate


154


and housing


128


from tank


12


.





FIG. 5

illustrates an embodiment of tank


12


having an internally mounted fluid level sensor


156


disposed proximate an opening


158


in tank


12


. A housing


160


is rotatably sealed within opening


158


, and is removable to provide access to sensor


156


. Sensor


156


may be attached to tank


12


by a bracket


162


accessible through opening


158


. Electrical penetration assembly


150


, as previously described with respect to

FIG. 4

, provides power and/or signal connections for sensor


156


. Housing


162


may include one or more other openings for appropriate fluid, electrical, or mechanical penetrations, such as fuel line assembly


164


. Electrical penetration assembly


150


may be retained within opening


166


by the friction of O-ring


168


against the walls of opening


166


, or an additional mechanical means of retention (not shown) may be provided. In this embodiment, as with those described above, the use of a radial O-ring seal apparatus facilitates the rotational movement of the various fuel tank penetrations within housing


160


without adversely affecting the seal provided therebetween.




It may be appreciated that fuel storage and supply apparatus


22


of

FIG. 1

containing one or more of the features illustrated in

FIGS. 2 through 5

provides the designer of a watercraft


10


with improved flexibility of design when compared to prior art fuel storage and supply apparatus. For example, it is not uncommon for a manufacturer to design and to sell a watercraft that is complete in ever respect except for the selection of the power unit. A fuel tank may be supplied with the boat, however, the connections between the power unit and the fuel tank will remain incomplete until the power unit is later specified. Changes in the tank connections and routing of the fuel system lines is made more difficult by the fixed connections found on prior art fuel tanks. By using a housing having multiple penetrations with individually rotatable connections, a variety of optional power units may be accommodated into a previously installed tank assembly. Similarly, a single tank may be stocked for a variety of applications, with each application being accommodated by the use of a specifically selected housing assembly installed within a single standardized opening of the tank. Furthermore, the installation and maintenance of a watercraft fuel system may be simplified by the ability to rotate various connections to a fuel tank without adversely affecting the effectiveness of the fluid seal for those connections.




Thus, a method of assembling a watercraft may include the steps of providing a hull; providing a fuel tank having an opening formed therein; installing the fuel tank in the hull; assembling a power unit to the hull; selecting a fuel tank opening housing having connections corresponding to the power unit; installing the fuel tank opening housing into the fuel tank opening; and installing a fuel line between the housing and the power unit. This is especially useful if the manufacturer provides at least two different customer-specified power units for use in a watercraft, and the power units each require different fuel tank connections. By providing a plurality of corresponding tank opening housings, each fuel tank opening housing having connections corresponding to a respective one of the power units, the appropriate connections can be more easily installed after the tank is in place by simply installing the appropriate tank opening housing. Installation is further simplified by the ability to rotate the penetrations passing through the housing without adversely affecting the effectiveness of the O-ring seal.




It may be further appreciated that the use of a single housing having a plurality of rotatable connections will provide a simplified method and apparatus for the modification of the fuel storage and supply system of a watercraft. This may occur, for example, in the event that a pressurized fuel system is approved for use on a watercraft that had previously utilized a suction fuel system. A modification kit may be assembled including an in-tank pump and an appropriate housing assembly having multiple fuel supply, vent fill, and electrical connections, as appropriate.




While the preferred embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes and substitutions will occur to those of skill in the art without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims.



Claims
  • 1. A watercraft fuel storage and supply apparatus comprising:a fuel tank having an opening formed therein; a housing attached to the fuel tank within the opening, the housing having a pair of openings formed therethrough; a pair of tubes, each disposal through a respective housing opening and rotatable therewithin, each tube secured to the housing independently by a respective mounting bracket; and a seal disposed between each opening and a respective tube.
  • 2. The watercraft fuel storage and supply apparatus of claim 1, further comprising:a fuel line attached to the tube and extending to a bottom portion of the tank; and a replaceable fuel filter attached to the fuel line.
  • 3. The watercraft fuel storage and supply apparatus of claim 1 wherein the housing is attached to the fuel tank by a threaded connection.
  • 4. The watercraft fuel storage and supply apparatus of claim 1, wherein the tube further comprises:a groove formed in the outside diameter surface of the tube for receiving and retaining a radial O-ring seal; a flange formed in the outside surface of the tube, the flange having a diameter greater than the diameter of the housing opening and having a bottom surface disposed against a top surface of the housing; and a clamping plate removably attached to the housing and covering at least a portion of the flange for retaining the tube within the housing opening.
  • 5. The watercraft fuel storage and supply apparatus of claim 1, further comprising:a valve cavity formed within the housing and in fluid communication between the interior and exterior of the tank; a check valve disposed within the valve cavity; a fuel outlet nozzle rotatably disposed within the valve cavity; and a radial O-ring seal disposed between the fuel outlet nozzle and a wall of the valve cavity.
  • 6. The watercraft fuel storage and supply apparatus of claim 5, wherein the check valve further comprises:a plate disposed within the valve cavity and sealed thereto about its perimeter; a hole formed in the plate for the passage of fuel therethrough; and an elastomer attached to the plate and extending therefrom to cover the hole, the elastomer operable to bend to permit fuel to pass out of the tank through the hole, and operable to seal the hole in the event of the flow of fuel into the tank.
  • 7. The watercraft fuel storage and supply apparatus of claim 1, further comprising:a further opening formed through the housing; and an electrical penetration sealingly disposed within the further opening.
  • 8. The watercraft fuel storage and supply apparatus of claim 7, further comprising:a pump assembly disposed within the tank and having an outlet connected to the tube; a wire connected between the pump assembly and the electrical penetration for supplying electrical power to the pump assembly.
  • 9. The watercraft fuel storage and supply apparatus of claim 8, further comprising a filter attached to an inlet of the pump assembly.
  • 10. The watercraft fuel storage and supply apparatus of claim 7, further comprising:a fluid level sensor disposed within the tank; and a wire connected between the fluid level sensor and the electrical penetration.
  • 11. A fuel storage and supply apparatus comprising:a tank having an opening formed therein; a housing sealingly disposal within the tank opening; a fill opening formed in the housing; a fill tube rotatably disposal within the fill opening; a seal disposed between the fill rube and the fill opening; a fuel supply opening formed in the housing; a fuel supply tube rotatably disposed within the fuel supply opening to allow rotation thereof past the fill tube; and a seal disposed generally between the fuel supply tube and a surface of the fuel supply opening.
  • 12. The fuel storage and supply apparatus of claim 11, further comprising a check valve disposed within the fuel supply opening.
  • 13. The fuel storage and supply apparatus of claim 12, wherein the check valve further comprises:a plate having a plurality of holes formed therein for the passage of fuel disposed in the fuel supply opening and sealed thereto along its perimeter; an elastomeric disc attached to the plate and extending to cover the outlet ends of the plurality of holes; and the elastomeric disc operable to bend to permit fuel to pass out of the tank through the plurality of holes, and operable to seal the plurality of holes in the event of the flow of fuel into the tank.
  • 14. The fuel storage and supply apparatus of claim 12, further comprising:a third opening formed in the housing; an electrical penetration disposed with the third opening; and a radial O-ring sealingly disposed between the electrical penetration and a surface of the third opening.
  • 15. The fuel storage and supply apparatus of claim 11 wherein the fill tube and the fuel supply tube are positionable with respect to one another such that each tube may face a common direction along a common axis.
  • 16. An apparatus for sealing an opening formed in a fuel tank, the apparatus comprising:a housing operable to be sealing disposed within an opening formed in a fuel tank; an opening formed through the housing; a tube rotatably disposed through the housing opening; and only one radial seal disposed between the housing opening and the tube, such that the only one radial seal permits rotation of the tube relative thereto.
  • 17. The apparatus of claim 16, further comprising:a second opening formed through the housing; a second tube disposed to pass through the second opening; and a radial O-ring sealingly disposed between the second opening and the second tube.
  • 18. The apparatus of claim 16, further comprising:a second opening formed through the housing; an electrical penetration disposed to pass through the second opening; and a radial O-ring sealingly disposed between the second opening and the electrical penetration.
  • 19. The apparatus of claim 16, further comprising a check valve sealingly disposed within the housing opening.
  • 20. The apparatus of claim 16, further comprising:a fuel line having a first end connected to the tube; and a filter connected to a second end of the fuel line.
  • 21. The apparatus of claim 20, further comprising a pump assembly connected between the filter and the fuel line.
  • 22. A kit comprising:a housing adapted to be sealingly disposed within an opening formed in a fuel tank, the housing having an opening formed therethrough; a tube adapted to be disposed through the housing opening; and a seal adapted to be disposed around the tube and between the tube and the wall or the housing opening for forming a sealed condition therebetween, such that the seal permits rotation of the tube relative thereto.
  • 23. The kit of claim 22, further comprising:a fuel line adapted to have a first end attached to the tube; and a filter adapted to be attached to a second end of the fuel line.
  • 24. The kit of claim 22, further comprising:the housing having a second opening formed therethrough; an electrical penetration adapted to be disposed through the second housing opening; and an O-ring adapted to be disposed around the electrical penetration and between the electrical penetration and the wall of the second housing opening for forming a seal therebetween.
  • 25. The kit of claim 24, further comprising:a pump assembly adapted to have its outlet attached to the tube; and a wire connected between the electrical penetration and the pump assembly.
  • 26. A watercraft comprising:a hull; a power unit attached to the hull; a fuel tank disposed in the hull, the fuel tank having an opening formed therein; a housing sealingly disposed in the tank opening, the housing having an opening formed therethrough; a fuel tube rotatably disposed through the housing opening to allow rotation past another fuel tube disposed through the housing; a seal disposed between the fuel tube and a wall of the housing opening; and a fuel line connected between the fuel tube and the power unit.
  • 27. The watercraft of claim 26, further comprising:a second opening formed through the housing; an electrical penetration sealingly disposed through the second opening; a pump disposed within the fuel tank and having an outlet connected to the fuel tube; and a wire connected between the pump and the electrical penetration.
  • 28. The watercraft of claim 27, further comprising a fuel filter attached to an inlet of the pump.
  • 29. The watercraft of claim 26, further comprising a filter disposed within the tank and connected to the tube opposed the fuel line.
  • 30. The watercraft of claim 26, wherein the housing is in threaded engagement with the tank.
  • 31. A watercraft fuel storage and supply apparatus comprising:a fuel tank having an opening formed therein; a housing positioned in the opening, the housing having a number of portholes; a number of rotatable penetrations positioned in the number of portholes and configured to provide fuel passage between an exterior and an interior of the fuel tank wherein each penetration is rotatable 360°; and a number of seals configured to seal the number of rotatable penetrations to the housing.
  • 32. The watercraft fuel storage and supply apparatus of claim 31 wherein the number of rotatable penetrations include at least one of a fuel line, a fill tube, a fuel supply tube, a vent tube, a fuel pump assembly, and an electrical penetration assembly.
  • 33. The watercraft fuel storage and supply apparatus of claim 31 wherein the number of seals include O-rings.
  • 34. The watercraft fuel storage and supply apparatus of claim 33 wherein an O-ring is radially disposed generally between a penetration and a surface of a porthole.
  • 35. The watercraft fuel storage and supply apparatus of claim 31 wherein one of the penetrations includes a fuel line extending to a lower portion of the fuel tank, the fuel line having a replaceable filter attached thereto.
  • 36. The watercraft fuel storage and supply apparatus of claim 33 wherein the O-ring is configured to permit rotation of a rotatable penetration about a longitudinal axis without comprising a sealed condition between the interior and the exterior of the fuel tank.
  • 37. The watercraft fuel storage and supply apparatus of claim 31 wherein each of the number of penetrations further comprises a locking apparatus configured to couple a penetration to the housing, the coupling restricting vertical movement of the penetration.
Parent Case Info

This application is a continuation of Ser. No. 09/620,457, filed Jul. 21, 2000, now U.S. Pat. No. 6,379,200.

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Continuations (1)
Number Date Country
Parent 09/620457 Jul 2000 US
Child 10/000176 US