JPH0579148U - Two-way valve for fuel evaporation prevention device - Google Patents

Abstract

(57) [Summary] [Purpose] A two-way valve for a fuel evaporation prevention device, which defines a gas-liquid separation chamber in which an obstacle is placed and liquefyes fuel vapor to prevent passage of liquefaction. To maintain the performance of and to prevent the canister from clogging. [Structure] A valve seat body 4 having a communication hole 4a is laterally provided in a casing 1 provided with an inlet pipe 2 and an outlet pipe 3. A bottomed tubular valve holding body 6 is mounted in the casing 1, an umbrella-shaped valve body 7 is arranged at the bottom thereof, and a cylindrical valve body 8 is fitted at the open end.
A spring 9 is interposed between the valve holder 7 and the casing 1 to press the cylindrical valve body 8 against the valve seat body 4. The obstacle 10 is arranged in the gas-liquid separation chamber 5b defined by the valve seat body 4 in the casing 1.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a two-way valve incorporated in a fuel vaporization prevention device that prevents the release of fuel vapor generated in a fuel tank of an automobile or the like into the atmosphere.

[0002]

[Prior Art]

 Conventionally, this type of two-way valve has a bottomed cylindrical valve holder mounted in a casing and an umbrella-shaped valve body provided at the bottom of the valve holder, as disclosed in Japanese Utility Model Publication No. 56-4930. A cylindrical valve body with a tip that gradually becomes thinner and a curved lip is formed at the upper end of the valve holder, and a spring is interposed between the bottom of the valve holder and the casing. Installed between the canisters, as the fuel vapor pressure in the tank rises, the valve holder is pushed down to let the fuel vapor flow to the canister side to reduce the internal pressure and protect the tank. When the number decreases, the umbrella-shaped valve element opens and the atmosphere is introduced from the canister to return the internal pressure to normal and prevent damage to the tank.

[0003]

[Problems to be solved by the device]

 By the way, when using this two-way valve, if fuel vapor condenses and re-liquefies and collects in the two-way valve, and comes into contact with a cylindrical valve body or umbrella-shaped valve body that is usually made of an elastic material such as rubber, Since the valve element swells and the hardness decreases, and it is deformed by subsequent re-drying, the operating pressure of the cylindrical valve element fluctuates, and the sealability of the umbrella-shaped valve element is impaired. Furthermore, this reliquefaction is highly soluble, and if the valve body and piping of the two-way valve are made of rubber, for example, it will dissolve additives and mold release agents, and will flow into the canister after passing through the two-way valve. Adhere to the filter, screen, etc., and the additives and release agents will be deposited in the form of grease and clog the filter.

[0004]

[Means for Solving the Problems]

 The present invention defines a valve chamber and a gas-liquid separation chamber by horizontally installing a valve seat body having a communication hole at the center on the inner wall of a casing of a tubular casing having an inlet pipe and an outlet pipe at both ends. Attach a bottomed cylindrical valve retainer to the bottom of the valve retainer, place an umbrella-shaped valve disc at the bottom of the valve retainer, and fit a cylindrical valve disc with a lip at the open end of the valve retainer. A spring is interposed between the bottom of the holder and the casing to bring the lip portion into pressure contact with the valve seat body, and an obstacle for bending the flow of fuel vapor is disposed in the gas-liquid separation chamber.

[0005]

[Action]

 When the fuel vapor is introduced into the two-way valve through the inlet pipe, the fuel vapor collides with an obstacle placed in the gas-liquid separation chamber and changes its flow, gradually progressing toward the valve seat body. During this time, the fuel vapor is condensed and liquefied and is stored in the gas-liquid separation chamber. If a two-way valve is used with its inlet pipe facing downwards, the liquefied substance returns to the fuel tank, and only fuel vapor that does not contain liquid passes through the communication hole of the valve seat body and pushes the cylindrical valve body toward the outlet pipe. ..

[0006]

【Example】

 The present invention will be described with reference to the embodiment shown in FIG. Reference numeral 1 denotes a casing, which is made of a synthetic resin material, and has a bottomed tubular lower body 1a having an inlet pipe 2 provided on the bottom wall and a bottomed tubular upper body 1b provided with an outlet pipe 3 on the bottom wall. The open ends of are fixed together. On the inner wall of the casing 1, a valve seat body 4 is provided in an airtight manner by being sandwiched between the open ends of the bodies 1a and 1b. The valve seat body 4 is made of a synthetic resin material, has a thin disk shape, and has a communication hole 4a communicating with both surfaces in the center thereof.

The inside of the casing 1 is partitioned by a valve seat body 4 to form a valve seat 5a and a gas-liquid separation chamber 5b, and the inside of the valve chamber 5a is made of a synthetic resin material and has a substantially H-shaped cross section. A bottomed cylindrical valve holder 6 having an annular insert with an L-shaped cross section fixed to one end thereof is mounted. The valve holder 6 has a mounting hole in the center of the bottom portion 6a, and a through hole is provided so as to surround the mounting hole, and the umbrella-shaped valve body 7 formed of an elastic material such as rubber in the mounting hole in the valve holder 6. Is fitted with the boss. The valve holder 6 is further provided with an L-shaped open end of the insert body and a lip portion which is made of an elastic material such as rubber and whose front end is gradually thinned and which is curved outward, and is provided with an annular groove on the outer peripheral wall. The valve body 8 is arranged with its open end fitted in the groove. In the valve chamber 5a, a coil-shaped spring 9 is arranged between the bottom 6a of the valve holder 6 and the bottom of the upper body 1b of the casing 1, and the cylinder is fitted to the valve holder 6. The lip portion of the valve body 8 is brought into pressure contact with the valve seat body 4 to close the communication hole 4a.

In the gas-liquid separation chamber 5b, an obstacle 10 filled with particles of a material having a relatively low specific heat such as glass or stainless steel is arranged with the mesh bodies 11a and 11b interposed therebetween. is there. The obstacle may be a spherical shape, a so-called Rahi-shiring ring shape, or a cylindrical shape. Further, as shown in FIG. 2, a substantially meniscus-shaped partition plate is alternately integrated on the inner wall of the cylindrical cylinder. It is also possible to dispose the obstacle 10a provided in the above and to bend the flow of fuel vapor by colliding it with the partition plate.

The fuel vapor introduced into the casing 1 through the inlet pipe 2 advances toward the valve seat body 4 while colliding with the obstacles 10 and 10a in the gas-liquid separation chamber 5b while colliding with the flow of the fuel vapor. To do. During this time, the fuel vapor is condensed and reliquefied on the surfaces of the obstacles 10 and 10a. If the casing 1 is attached to a vehicle or the like with the inlet pipe 2 facing downward, or if a new return pipe is installed, the liquefaction will return to the fuel tank in sequence, and only the fuel vapor containing no liquid will cause the valve seat body to rise only when its pressure rises. After passing through the communication hole 4a of No. 4, the valve holder 6 fitted with the cylindrical valve body 8 is pushed up and advances in the casing 1 toward the outlet pipe 3.

[0010]

[Effect of the device]

 As described above, according to the present invention, the casing of the two-way valve is divided into the valve chamber and the gas-liquid separation chamber, and the obstacle is arranged in the gas-liquid separation chamber. While colliding with the body, it condenses and liquefies while bending, and only fuel vapor that does not contain liquid enters the valve chamber, prevents the cylindrical valve body and umbrella valve body from swelling, and maintains its sealing property, which stabilizes the two-way valve. Performance can be maintained. Further, since the liquefied material does not pass through the two-way valve, clogging of the canister can be prevented and the function as a fuel evaporation prevention device can be secured.

[Brief description of drawings]

FIG. 1 is a sectional view of a two-way valve of the present invention.

FIG. 2 is a sectional view of a two-way valve according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 casing 2 inlet pipe 3 outlet pipe 4 valve seat body 4a communication hole 6 valve holding body 7 umbrella-shaped valve body 8 cylindrical valve body 9 spring 10, 10a obstacle body

Claims (1)

[Scope of utility model registration request] 1. A valve seat body having a communication hole in the center is laterally provided on the inner wall of a casing of a tubular casing having an inlet pipe and an outlet pipe at both ends to define a valve chamber and a gas-liquid separation chamber, and a valve. A cylindrical valve holder with a bottom is mounted in the chamber, an umbrella-shaped valve element is arranged at the bottom of the valve holder, and a cylindrical valve element having a lip portion at the open end is fitted to the valve holder. A spring is interposed between the bottom portion and the casing to bring the lip portion into pressure contact with the valve seat body,
A two-way valve for a fuel evaporation prevention device that has an obstacle in the gas-liquid separation chamber.