초록 ▼

A fuel tank venting system for a boat (10) includes a fuel tank (12) the interior of which is open to a filler tube (14) and a vent line (18). A liquid separation and recovery device (20) is connected to the vent line and an outlet line (28) which is open to atmosphere. Vapor delivered to the device

A fuel tank venting system for a boat (10) includes a fuel tank (12) the interior of which is open to a filler tube (14) and a vent line (18). A liquid separation and recovery device (20) is connected to the vent line and an outlet line (28) which is open to atmosphere. Vapor delivered to the device through the vent line enters an inlet (24) and passes through an opening (64). The vapor then passes through a screen (86), around a sphere (82) that is buoyant in the liquid fuel, and escapes from the device through an outlet (26). When liquid fuel enters the device, the sphere rises blocking flow to the outlet. The trapped liquid passes through an opening (48) into a cavity (42). The liquid entering the cavity displaces a spring loaded piston (56). When liquid is no longer being delivered to the cavity, the piston pushes the liquid back out the inlet and down the vent line to the fuel tank. In excess pressure situations, when liquid is being delivered to the device, a movable member (66) is displaced upward opening a flow path to the outlet of the device through a second chamber (62). Once the over-pressure condition has subsided, the movable member returns to its original condition to prevent the passage of liquid through the device.

대표청구항 ▼

1. Apparatus for preventing the discharge of a liquid through a vent line from a tank containing said liquid while enabling vapor to pass therethrough, comprising: a body, said body including an inlet and an outlet, the inlet in fluid communication with the vent line from said tank and the outlet

1. Apparatus for preventing the discharge of a liquid through a vent line from a tank containing said liquid while enabling vapor to pass therethrough, comprising: a body, said body including an inlet and an outlet, the inlet in fluid communication with the vent line from said tank and the outlet in fluid communication with atmosphere, said body further including expandable chamber means in fluid communication with said inlet and said outlet for expanding and contracting in area in proportion to fluid pressure; vapor valve means adjacent said outlet for enabling vapor to pass therethrough while preventing the passage of liquid; whereby when liquid is delivered to said apparatus through said vent line said liquid is prevented from passing through said apparatus by said vapor valve means and said liquid held in said body increases said fluid pressure which expands the area of said expandable chamber means and is held therein until said fluid pressure falls and said liquid is expelled from said expandable chamber means. 2. The apparatus according to claim 1, and further comprising return means for returning liquid expelled from said expandable chamber means to said tank. 3. The apparatus according to claim 2 and further comprising relief valve means in fluid communication with said expandable chamber means and said outlet, for enabling liquid to pass from said inlet to said outlet when a relief pressure is exceeded in said expandable chamber means. 4. The apparatus according to claim 1 wherein said expandable chamber means comprises: a cylindrical cavity in said body, said cavity having a first end and a second end, said first end in fluid communication with said inlet; a movable piston means in said cavity for preventing the passage of fluid to the second end of said cavity; biasing means for biasing said piston means towards said first end of said cylindrical cavity; whereby liquid delivered to said apparatus moves said piston means toward the second end of said cavity and said liquid is held in the first end of said cavity; and when said liquid is no longer delivered to said apparatus said biasing means moving said piston means towards said first end of said cavity to return liquid in said cavity to said tank through said vent line. 5. The apparatus according to claim 4 wherein: said body includes a first opening to said first end of said cavity, said first opening in fluid communication with said inlet; said piston means includes a first side adjacent said first end of said cavity and a second side adjacent said second end of said cavity; and said apparatus further comprising: expandable membrane means for preventing the passage of fluid therethrough, said membrane means intermediate of said first opening and said piston means, said first side of said piston means supporting said membrane means. 6. The apparatus according to claim 5 and further comprising; vent outlet means for enabling air to escape from the second end of said cavity upon movement of said piston means towards said second end. 7. The apparatus according to claim 6 wherein said vent outlet means is vented to atmosphere. 8. The apparatus according to claim 7 wherein the outlet of said apparatus is in fluid communication with an outlet line and said vent outlet means is in fluid communication with said outlet line. 9. The apparatus according to claim 6 and further comprising: relief valve means in fluid communication with said inlet and said outlet, for enabling liquid to pass from said inlet to said outlet when a relief pressure is exceeded. 10. The apparatus according to claim 9 wherein said body further comprises a chamber, said chamber in fluid communication with said inlet, said outlet and said first opening to the first end of said cylindrical cavity; said apparatus further comprising: a second opening from said chamber to said vapor valve means, said vapor valve means including: an impermeable body buoyant in said liquid; and a seat located vertically above said buoyant body, said seat intermediate said second opening and said outlet, said seat having a flow passage therein, said buoyant body sized for blocking said flow passage; whereby said buoyant body blocks fluid flow through said flow passage in said seat when liquid enters said vapor valve means and prevents liquid flow to said outlet. 11. The apparatus according to claim 10 wherein said buoyant body is a sphere and said flow passage is a circular opening therethrough. 12. The apparatus according to claim 11 and further comprising a screen in said second opening. 13. The apparatus according to claim 11 wherein said relief valve means comprises: a movable member, said seat and opening therethrough on said movable member; a relief passage extending through said body and adapted for passing fluid from said second opening to said outlet; and wherein when said buoyant body blocks flow through said opening, said relief pressure moves said movable member to open said relief passage enabling liquid to pass to the outlet therethrough. 14. The apparatus according to claim 13 wherein said body further comprises: a second cavity vertically above said second opening, said second cavity sized for enabling movement of said movable member therein, said second cavity bounded by a sealing surface adjacent said second opening; and wherein said movable member includes a recess sized for holding said buoyant body vertically below said seat while enabling vapor to flow through said recess; said movable member further including a face, said face adjacent said sealing surface and preventing the flow of fluid from said second opening to said second cavity when said face of said movable member is in a first position abutting said sealing surface; and, spring means for biasing said movable member to the first position; whereby when said seat is blocked by said buoyant body due to liquid in said apparatus said relief pressure moves said movable member to enable liquid to pass to said outlet through said second cavity. 15. The apparatus according to claim 14 and further comprising a screen in said second opening. 16. A fuel tank venting system for a vehicle comprising: a fuel tank; a filler tube open to said fuel tank for delivering fuel to said tank; a vent line in fluid communication with said fuel tank for venting fluid from said tank; an outlet line to atmosphere; and a liquid return apparatus comprising: an inlet in fluid communication with said vent line; an outlet in fluid communication with said outlet line; expandable chamber means in fluid communication with said inlet and said outlet for expanding and contracting in area in proportion to fluid pressure; vapor valve means adjacent said outlet for enabling vapor to pass to said outlet of said apparatus while blocking the passage of liquid; whereby when liquid is delivered to said apparatus through said vent line, said liquid is prevented from passing to said outlet by said vapor valve means and the liquid held in said body increases said fluid pressure which expands the area of said expandable chamber means and is held therein until said liquid pressure falls and said liquid is expelled from said expandable chamber means. 17. The fuel tank venting system according to claim 16 wherein said liquid return apparatus further comprises relief valve means in fluid communication with said expandable chamber means and said outlet for enabling liquid to pass from said inlet to said outlet when a relief pressure is exceeded. 18. The fuel tank venting system according to claim 17 wherein said liquid return apparatus has a body and said expandable chamber means comprises: a cylindrical cavity in said body, said cavity having a first end and a second end, said first end in fluid communication with said inlet; a movable piston means in said cavity for preventing the passage of fluid to said second end; biasing means for biasing said piston toward said first end of said cylindrical cavity; whereby liquid delivered to said apparatus displaces said piston in said cavity toward said second end and said liquid is held in said cavity, and when said liquid is no longer delivered to said apparatus, said biasing means moves said piston toward said first end expelling said liquid from said cavity and returning said liquid to said tank through said vent line. 19. Apparatus for preventing the discharge of a liquid through a vent line from a tank containing said liquid while enabling vapor to pass therethrough, comprising: a body, said body including an inlet and an outlet, the inlet in fluid communication with the vent line from said tank and the outlet in fluid communication with atmosphere; said body further including expandable chamber means in fluid communication with said inlet and said outlet for expanding responsive to fluid pressure; vapor valve means adjacent said outlet for enabling vapor to pass therethrough while preventing the passage of liquid; and separating means positioned in said body between said inlet and said outlet for separating liquid from vapor delivered from said tank; whereby liquid is prevented from passing through said apparatus by said vapor valve means and said liquid expands expandable chamber means and is held therein.