Overflow cut-off valve

Abstract

The invention discloses an overflow cut-off valve. When a fuel tank is toppled, a valve floating core is in an inclined state; the weight of the lower part of the valve floating core is greater than that of the upper part of the valve floating core; the valve floating core is slightly staggered relative to an inner cavity of a valve casing; the valve floating core is not fixedly connected with a sealing element but a supporting pillar on the valve floating core provides a pivot for the sealing element and the sealing element can swing along the pivot; when the fuel tank is toppled, a return spring overcomes a resolution force of the gravity of the valve floating core to eject the valve floating core forwards and a sealing assembly leans against the lower end face of a ventilation hole; greater air pressure in the fuel tank acts on the inner side of the sealing assembly, so that the sealing assembly swings and a sealing surface on the sealing element is tightly attached to the ventilation hole. Compared with the traditional rubber valve with the fixed valve floating core, the overflow cut-off valve disclosed by the invention has the characteristics that the sealing element of the valve floating core can adjust the angle and seal the ventilation hole under the action of internal air pressure, and thus the fuel leakage of the fuel tank in a toppling state is further reduced.

Description

technical field [0001] The invention relates to a valve body, in particular to an overflow cut-off valve. Background technique [0002] An overflow cut-off valve is usually installed on the vehicle fuel tank, which has the following functions: 1) When the vehicle fuel tank is filled with oil, the vehicle fuel tank and the atmosphere have a certain passage through the overflow cut-off valve; and when the vehicle fuel tank is filled with fuel, The spill shut-off valve automatically closes to prevent fuel from spilling out of the spill shut-off valve. 2) The last important thing is that when the position of the fuel tank changes suddenly (such as a vehicle overturning), the overflow cut-off valve will prevent the fuel from flowing out. Flow cut-off valve", which discloses that the upper end of the valve housing is provided with an air inlet hole, and the valve housing is provided with a valve floating core that can float up and down in the valve housing. The valve floating co...

AI Technical Summary

Problems solved by technology

[0004] The air inlet and outlet passages of this structure have the following problems: when the fuel tank is dumped, the valve floating core is in a tilted state. Since the lower part of the valve floating core is heavier than the upper part, the valve floating core is slightly misaligned relative to the inner cavity of the valve housing. And the rubber valve is attached to the surface of the floating core of the valve, so there must be a certain inclination or misalignment of the rubber valve relative to the air intake hole, so that it cannot be completely matched with the air intake hole. There will be some incomplete sealing, so that the rubber valve cannot completely block the air intake hole, which will cause a small amount of fuel leakage

Images