Fluid handling – Control by change of position or inertia of system – Vent opening or closing on tipping container
Reexamination Certificate
2000-10-17
2001-10-16
Chambers, A. Michael (Department: 3753)
Fluid handling
Control by change of position or inertia of system
Vent opening or closing on tipping container
C137S587000, C137S588000, C141S059000, C141S198000, C123S516000
Reexamination Certificate
active
06302133
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a fuel tank having a seal member provided at a fuel entry port provided at an upper end of a filler pipe continuously extending to a tank main body for sealing an outer circumference of a nozzle of a fuel filling gun adapted to be inserted into the fuel entry port, or a float valve adapted to close when the fuel level in the tank main body rises and when a vehicle rolls over.
2. Description of the Related Art
A fuel tank of an automobile has a fuel entry port provided at an upper end of a filler pipe extending upwardly from a tank main body, and the nozzle of a fuel filling gun is inserted into a seal member provided at the fuel entry port for refueling. When the fuel level of the tank main body is raised by refueling until the fuel tank becomes full, a float valve is closed to suppress the rise of the fuel level in the fuel tank, and therefore when refueling continues further, the fuel level of the filler pipe then rises. Then, when the nozzle of the fuel filling gun submerges under the fuel level of the filler pipe due to the rise of the latter, an automatic fill-stop device of the fuel filling gun is actuated to thereby prevent the excessive refueling.
In addition, when the fuel level in the tank main body rises due to fueling, vaporized fuel is pushed out into a charging passage from the tank main body through the float valve for adsorption by a canister, whereby the emission of vaporized fuel to the atmosphere is prevented. Moreover, when the fuel level in the filler pipe rises after the float valve closes in accordance with the rise of the fuel level in the tank main body, vaporized fuel pushed out from the filler pipe by the rising fuel is supplied to the canister via the breather pipe and the charging passage.
However, when the automatic fill-stop device fails for some reason to thereby cause an excessive refueling and the fuel level in the fuel filler pipe rises over the limit, since the fuel entry port at the upper end of the filler pipe is closed with the nozzle of the fuel filling gun inserted into the seal member, the internal pressures of the tank main body and the filler pipe rise as refueling continues, whereby the tank main body or the filler pipe may be deformed or the nozzle of the fuel filling gun may be dislocated from the seal member at the fuel entry port, leading to a leakage of fuel.
Further, when excessive fueling occurs due to the failure of an automatic fill-stop device of a fuel filling gun or carelessness of the operator of a fuel filling pump, there is a risk that fuel flows into the canister from the filler pipe after passing through the breather pipe and the charging passage. In addition, since the float valve closes when the vehicle rolls over, although there is no risk that fuel inside the tank main body directly flows into the canister through the charging passage, there is a possibility that fuel inside the tank main body flows into the canister after passing through the breather pipe and the charging passage from the filler pipe.
SUMMARY OF THE INVENTION
The present invention was made in view of the aforesaid conditions, and an object thereof is to prevent the deformation of the fuel tank or the outflow of fuel in the even that there occurs an excessive fueling in conjunction with the failure of the automatic fuel fill-stop device of the fuel filling gun, and another object thereof is to ensure that fuel inside the filler pipe is prevented from flowing into the canister through the breather pipe when fuel is supplied excessively or the vehicle rolls over.
With a view to attaining the above object, according to a first aspect of the invention, there is provided a fuel tank having a seal member provided at a fuel entry port provided at an upper end of a filler pipe continuously extending to a tank main body for sealing an outer circumference of a nozzle of a fuel filling gun adapted to be inserted into the fuel entry port, the fuel tank comprising; a first relief valve and a second relief valve which are adapted to open when the internal pressure of the filler pipe reaches or exceeds a predetermined value, wherein the first relief valve allows the interior of the filler pipe to communicate with the atmosphere, while the second relief valve allows the interior of the filler pipe to communicate with the fuel entry port located above the seal member.
According to the aforesaid construction, since there is provided the first relief valve adapted to open when the internal pressure of the filler pipe reaches or exceeds the predetermined value due to excessive fueling to thereby allow the interior of the filler pipe to communicate with the atmosphere, the internal pressure of the filler pipe can be reduced by opening the first relief valve when excessive fueling takes place. This obviates the necessity of imparting the tank main body and the filler pipe a strength which can withstand the excessive internal pressure and therefore contributes to the reduction in weight of the tank main body and the filler pipe. Moreover, the construction can prevent the outflow of the fuel resulting from the dislocation of the nozzle of the fuel filling gun from the seal member due to the excessive internal pressure. In addition, there is also provided the second relief valve adapted to open when the excessive fueling takes place to thereby allow part of fuel within the filler pipe to flow out into the fuel entry port located above the seal member, the operator of the fuel filling pump can be informed of the occurrence of an abnormal situation to thereby prompt him or her to stop fueling.
Further, according to a second aspect of the invention, there is proposed a fuel tank wherein an upper space of tank main body is connected to a canister via a charging passage, wherein an upper space of a filler pipe communicating with the tank main body is connected to the charging passage via a breather pipe and wherein a float valve adapted to close when the fuel level in the tank main body rises and when a vehicle rolls over is provided at a portion where the charging passage is connected to the tank main body, the fuel tank comprising, an overflow valve adapted to close by virtue of a buoyancy caused by fuel when the fuel level in the filler pipe rises, and a rollover valve adapted to close by virtue of the gravity thereof when a vehicle rolls over, the overflow valve and the rollover valve being provided along the breather pipe.
According to the above construction, since the overflow valve adapted to close by virtue of a buoyancy caused by fuel when the fuel level in the filler pipe rises is provided along the breather pipe connecting the upper space in the filler pipe to the canister via the charging passage, it is ensured by the closure of the overflow valve that fuel in the filler pipe is prevented from flowing into he canister through the breather pipe when fuel is supplied excessively. In addition, since the rollover valve is provided along the breather pipe which adapted to close when the vehicle rolls over, it is ensured by the closure of the rollover valve that fuel in the filler pipe is prevented from flowing into the canister through the breather pipe.
REFERENCES:
patent: 4934417 (1990-06-01), Bucci
patent: 5040575 (1991-08-01), Oeffling et al.
patent: 5056494 (1991-10-01), Kayanuma
patent: 5730194 (1998-03-01), Foltz
patent: 5979417 (1999-11-01), Hyodo et al.
Fujino Ryuji
Ichitani Toshiaki
Kobayashi Makoto
Shimizu Yoshihiro
Suzuki Takeshi
Arent Fox Kintner & Plotkin & Kahn, PLLC
Chambers A. Michael
Honda Giken Kogyo Kabushiki Kaisha
McShane Thomas L.
LandOfFree
Fuel tank does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Fuel tank, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fuel tank will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2606237