JPH0326300Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to an evaporated fuel control valve interposed between a fuel tank and a canister.

(Prior art) Conventionally, when the pressure of evaporated fuel gas in the fuel tank exceeds a predetermined level, the valve opens to send fuel gas to the canister, and when the fuel tank becomes negative pressure, the valve opens to send in atmospheric air. A two-way valve that opens as if to open is provided between the fuel tank and the canister.
An example is shown in FIG. The two-way valve 1 includes an annular valve body 4 and an umbrella-shaped valve body 8 in a casing formed by a body 2 having a pipe 2a connected to a fuel tank and a cover 3 having a pipe 3a connected to a canister. A retainer 5 is installed. An opening 5a provided in the retainer 5 is always closed by an umbrella-shaped valve body 8, and is opened when the fuel tank side is at high pressure, opening a passage from the pipe 3a to the canister via the central opening 4b of the annular valve body. Further, the annular valve body 4 is closed when the spring 6 presses the retainer 5 and its lip 4a is pressed against the valve seat 3b provided at the base of the pipe 3a.When the fuel tank side becomes negative pressure, the annular valve body 4 is closed. 6, the valve opens and air flows in from the pipe 3a.

(Problem to be solved by the invention) In such a two-way valve, the valve that opens in the direction in which fuel flows out is an umbrella-shaped valve made of an elastic body, and in order to allow the evaporated fuel gas to be sent to the canister side in a timely manner. The valve opening pressure cannot be set too high. Therefore, the vehicle overturned and the liquid fuel leaked into pipe 2.
When it flows in from a, there is a risk that it will not be able to be stopped and it will flow out. Therefore, a rollover valve must be provided separately from this two-way valve. In the conventional two-way valve structure, two valve bodies are provided on the central axis of the casing, so it is difficult to integrate the rollover valve into a compact valve.

(Means for solving the problem) The evaporative fuel control valve of this invention has the following configuration.
That is, the inside of the casing is divided into an upper chamber and a lower chamber by a partition wall having a central opening and side openings, and the upper chamber is provided with a first valve body that covers the central opening and is pressed by a spring and opens only upward. The chamber is provided with an umbrella-shaped second valve body made of an elastic material that covers the side opening from below so that the valve opens only downwards, and the lower chamber is further equipped with a sphere that rolls on the slotted bottom wall. and,
A third valve body is provided which holds the sphere and whose upper end faces the lower surface of the central opening. The third valve body is normally open, and when the spherical body moves up the cone-shaped bottom wall due to the inclination of the casing, it is pushed up and closes the central opening from below.

(Function) The evaporated fuel control valve of this invention having the above-mentioned configuration has a rollover valve formed by the third valve body in the lower chamber and the lower surface of the central opening, and a two-way valve consisting of the first and second valve bodies, and a rollover valve formed by the first and second valve bodies. Physically, they are arranged in the same casing, making them compact. Moreover, even if liquid fuel flows into the lower chamber when the vehicle rolls over, the third valve body acts to close the central opening, and at the side openings, the pressure of the liquid fuel acts on the umbrella-shaped valve body in the valve closing direction. There was no leakage of fluid fuel.

(Example) Fig. 2 shows an example of this invention. The evaporated fuel control valve 11 shown in FIG. 2 has a pipe-shaped upper opening 12.
an upper case 12 having a diameter of 1.a, and a lower case 13 having a lower opening 13a in a cone-shaped bottom wall.
are fixed across the partition wall 14 to form a casing, and the partition wall 14 separates the upper chamber 15 and the lower chamber 1.
It is divided into 6. The partition wall 14 is provided with a central opening 14a and side openings 14b on the sides. A cup-shaped first valve body 17 made of an elastic synthetic resin material is disposed in the upper chamber 15 so as to cover the central opening 14a, and a spring 19 presses a retainer 18 attached to the first valve body 17. An umbrella-shaped valve 20 made of a synthetic resin elastic material is attached to the partition wall 14 so as to cover the side opening 14b from below. A sphere 2 that can freely roll on the bottom wall of the lower case 13 in the lower chamber 16
A third valve element 22 is provided, which includes a leg part 22a on which the valve 1 is placed and holds it from above, and a valve rod 22b extending upward from the leg part 22a. The tip of the valve stem 22b faces the central opening 14a at an appropriate distance, and is slidably supported by a tapered portion 14c on the periphery of the lower surface of the central opening 14a.

This evaporated fuel control valve is used with the lower opening 13a communicating with the fuel tank and the upper opening 12a communicating with the canister. Evaporated gas from the fuel tank passes through the lower opening 13a and the central opening 14a, and when the pressure reaches a predetermined pressure or higher, it pushes open the first valve body 17 and flows out from the upper opening 12a. When the pressure in the fuel tank becomes negative, air enters through the upper opening 12a, pushes open the second valve body 20 through the side opening 14b, and supplies air to the fuel tank through the lower opening 13a. Further, when the vehicle rolls over, the sphere 21 relatively moves up the slope of the bottom wall, pushes up the third valve body 22, and closes the central opening 14a. At this time, even if liquid fuel flows into the lower chamber, the second valve body 20 is pressurized by the fuel in the direction of closing, so no fuel flows out.

(Effects) The evaporated fuel control valve of this invention has a compact structure because the second valve body is located away from the center axis of the casing and the rollover valve is housed in an integrated casing, and it connects the fuel tank and canister. Simply attaching this control valve to the pipe simplifies piping and reduces the number of connection points that may pose a danger such as fuel leakage. Furthermore, since the umbrella-shaped valve is oriented so that it is pressurized by the liquid fuel, the liquid fuel shutoff effect is also reliable.

[Brief explanation of drawings]

FIG. 1 shows a conventional two-way valve, and FIG. 2 shows an embodiment of this invention. 12... Upper case, 13... Lower case, 1
4...Partition wall, 14a...Central opening, 14b...
Side opening, 17...first valve body, 20...second valve body, 21...spherical body, 22...third valve body.

Claims (1)

[Scope of utility model registration request] A casing is provided in which an upper chamber having an upper opening and a lower chamber having a bottom wall inclined in the shape of a bevel and having a lower opening are defined by a partition wall having a central opening and side openings, and the casing is pressed into the upper chamber by a spring. A first valve body is disposed to cover the central opening from above, and a second umbrella-shaped valve body made of an elastic material is attached to the partition wall to cover the side opening from below. A rotatable sphere is disposed in the third valve body, and a third valve body is provided, which is composed of legs that hold the sphere from above and a valve stem extending upward from the legs, with the tip of the valve stem facing the lower surface of the central opening. An evaporated fuel control valve formed by opening and closing the valve to form an on-off valve.