# US 9,518,671 B2 · Valve device for fuel tank > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,518,671 B2 - Document ID: US9518671B2 - Status: Granted - Kind: B2 - Application number: 14/374,718 - Filed: 2013-03-18 - Published: 2015-02-05 - Granted: 2016-12-13 - Earliest claimed: 2012-03-22 - Assignees: Nifco Inc. - Applicants: Nifco Inc. - Inventors: Xiaohui Sui - Web page: https://patentgrep.com/patent/US9518671B2 ## CPC - F16K 24/042: {actuated by a float} - F16K 24/044: {the float being rigidly connected to the valve element, the assembly of float and valve element following a substantially translational movement when actuated, e.g. also for actuating a pilot valve} - F16K 27/02: of lift valves (for reducing the flow resistance of screw-spindle lift-valves F16K1/06) - B60K 15/03519: {Valve arrangements in the vent line} - F02M 25/0836: {Arrangement of valves controlling the admission of fuel vapour to an engine, e.g. valve being disposed between fuel tank or absorption canister and intake manifold} - F02M 37/20: characterised by means for preventing vapour lock - Y10T 137/0874: Vent opening or closing on tipping container - Y10T 137/3099: Float responsive - F16K: VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING {(devices for emptying and evacuating the excess liquid in valves or conduits F16L55/07)} - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A valve device is attached to a fuel tank. The valve device includes a case including a vent valve port communicating outside of the tank at an upper portion, and including an inflow portion for a fuel below the vent valve port; and an upper floor body inside the case and rising by the fuel flowing into the case to be seated in the vent valve port. In a face portion facing a bottom portion of the upper float body in the case, an elastic piece is formed by a first arc-shaped split groove such that a center side of the face portion becomes a curvature inner side, and a second arc-shaped split groove formed such that a center of the face portion becomes a curvature inner side outside the first arc-shaped split groove. One portion of the elastic piece abuts against the bottom portion of the upper float body. ## Claims ### Claim 1 A valve device for a fuel tank, adapted to be attached to a fuel tank, comprising: a case including a vent valve port communicating with an outside of the fuel tank at an upper portion, and including an inflow portion for a fuel below the vent valve port; and a float body which is located inside the case and rises by the fuel flowing into the case so as to be seated in the vent valve port, wherein in a face portion facing a bottom portion of the float body in the case, an elastic piece is formed by a first arc-shaped split groove formed such that a center of the face portion becomes a curvature inner side, and a second arc-shaped split groove formed outside the first arc-shaped split groove such that the center of the face portion becomes a curvature inner side, the elastic piece has an arc-shape in which the center of the face portion becomes a curvature inner side, one portion of the elastic piece abuts against the bottom portion of the float body, the elastic piece is disposed in the face portion between the first arc-shaped split groove and the second arc-shaped split groove, the first arc-shaped split groove, the second arc-shaped split groove, and the elastic piece have an arc-shape curving around a center axis of the case, and the face portion further comprises a communicating portion communicating the first and second arc-shaped split grooves, the communicating portion comprising a first groove extending radially outwardly from one groove end of the first arc-shaped split groove, and extending beyond the second arc-shaped split groove; a second groove extending radially outwardly from one groove end of the second arc-shaped split groove; and a third groove extending perpendicular to the first and second grooves to communicate the first and second grooves. ### Claim 2 (depends on 1) A valve device for a fuel tank according to claim 1, wherein in a direction around the center of the face portion of the case, two or more elastic pieces are provided at an interval between adjacent elastic pieces. ### Claim 3 (depends on 1) A valve device for a fuel tank according to claim 1, wherein the case has a cylindrical shape, and the elastic piece is formed along an arc of a virtual circle around a cylinder axis of the case. ### Claim 4 (depends on 1) A valve device for a fuel tank according to claim 1, wherein the elastic piece extends radially outwardly toward the third groove of the communicating portion, and the elastic piece includes a free end surrounded by the first, second, and third grooves, the free end having an abutment portion protruding toward the bottom portion of the floating body. ### Claim 5 (depends on 1) A valve device for a fuel tank according to claim 1, wherein the elastic piece includes a free end with an abutment portion protruding relative to the bottom portion of the float body. ### Claim 6 (depends on 5) A valve device for a fuel tank according to claim 5, wherein the communication portion is formed such that a width of the free end of the elastic piece is larger than that of a rest of the elastic piece. ### Claim 7 A valve device for a fuel tank, adapted to be attached to a fuel tank, comprising: a case including a vent valve port communicating with an outside of the fuel tank at an upper portion, and including an inflow portion for a fuel below the vent valve port; and a float body which is located inside the case and rises by the fuel flowing into the case so as to be seated in the vent valve port, wherein in a face portion facing a bottom portion of the float body in the case, an elastic piece is formed by a first arc-shaped split groove formed such that a center of the face portion becomes a curvature inner side, a second arc-shaped split groove formed outside the first arc-shaped split groove such that the center of the face portion becomes a curvature inner side, and a communication portion communicating between groove ends of the first and second arc-shaped split grooves, and a communication portion side becomes a free end, one portion of the elastic piece abuts against the bottom portion of the float body, in the free end of the elastic piece, an abutment portion relative to the bottom portion of the float body is protruded, by a third arc-shaped split groove formed outside the second arc-shaped split groove such that the center of the face portion of the case becomes a curvature inner side; and a supplemental communication portion communicating between one groove end of the second arc-shaped split groove and one groove end of the third arc-shaped split groove, a supplemental elastic piece in which a communication portion side is a free end is formed, and in the free end of the supplemental elastic piece, an abutment portion relative to the bottom portion of the float body is protruded. ### Claim 8 A valve device for a fuel tank, adapted to be attached to a fuel tank, comprising: a case including a vent valve port communicating with an outside of the fuel tank at an upper portion, and including an inflow portion for a fuel below the vent valve port; and a float body which is located inside the case and rises by the fuel flowing into the case so as to be seated in the vent valve port, wherein in a face portion facing a bottom portion of the float body in the case, an elastic piece is formed by a first arc-shaped split groove formed such that a center of the face portion becomes a curvature inner side, and a second arc-shaped split groove formed outside the first arc-shaped split groove such that the center of the face portion becomes a curvature inner side, the elastic piece has an arc-shape in which the center of the face portion becomes a curvature inner side, one portion of the elastic piece abuts against the bottom portion of the float body, the first arc-shaped split groove, the second arc-shaped split groove, and the elastic piece have an arc-shape curving around a center axis of the case, the face portion further comprises a communicating portion extending radially at intermediate positions of the first and second arc-shaped split grooves to communicate the first and second arc-shaped split grooves, and the elastic piece includes first and second elastic pieces wherein each of a free end of the first and second elastic pieces has an abutment portion. ### Claim 9 A valve device for a fuel tank, adapted to be attached to a fuel tank, comprising: a case including a vent valve port communicating with an outside of the fuel tank at an upper portion, and including an inflow portion for a fuel below the vent valve port; and a float body which is located inside the case and rises by the fuel flowing into the case so as to be seated in the vent valve port, wherein in a face portion facing a bottom portion of the float body in the case, an elastic piece is formed by a first arc-shaped split groove formed such that a center of the face portion becomes a curvature inner side, and a second arc-shaped split groove formed outside the first arc-shaped split groove such that the center of the face portion becomes a curvature inner side, the elastic piece has an arc-shape in which the center of the face portion becomes a curvature inner side, one portion of the elastic piece abuts against the bottom portion of the float body, the elastic piece is disposed in the face portion between the first arc-shaped split groove and the second arc-shaped split groove, the first arc-shaped split groove, the second arc-shaped split groove, and the elastic piece have an arc-shape curving around a center axis of the case, and the face portion further comprises a communicating portion communicating the first and second arc-shaped split grooves, the communicating portion comprising a first groove extending radially inwardly from one groove end of the first arc-shaped split groove; a second groove extending radially inwardly from one groove end of the second arc-shaped split groove and extending beyond the first arc-shaped split groove; and a third groove extending perpendicular to the first and second grooves to communicate the first and second grooves.