| 摘要 |
<p>A fuel tank venting system (1) includes a fuel cap (10), a vent diaphragm (12) and a vent disc (14). A valve cavity (22) with a substantially concave bottom is formed in a bottom of the fuel cap (10). At least one air passage (30) is formed through the vent disc (14). A substantially convex surface (32) is formed on a top of the diaphragm projection (28). The vent diaphragm (12) is retained between the substantially concave bottom (24) and the substantially convex surface (32). When air is needed for fuel flow, a vacuum within the fuel tank (100) pulls the perimeter of the vent diaphragm (12) downward, which breaks a seal with the substantially concave bottom (24) to allow air flow. In a second embodiment, the fuel tank venting system (2) is contained in a wall of the fuel tank (100). In a third embodiment, the fuel tank venting system (3) is contained in a fuel vent body (52), which is attached to the fuel tank (100).</p> |
