JPH066059Y2 - Vehicle fuel tank cap - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fuel tank cap for a vehicle.

2. Description of the Related Art Generally, as shown in FIG. 1, a cap 012 of a vehicle fuel tank 010 is sealed and screwed to a tank oil filler port 011 with a rubber packing 021.

In the conventional example of this cap (Actual No. 50-39617), the second
As shown in the figure, attach the cap 01 to the fuel filler port 011 of the fuel tank 010.
2 is screwed on, and rubber packing is attached to the cap 012 main body.
A valve chamber 013 is provided via 021, and a breather hole 014, which is a ventilation path for communicating the inside of the fuel tank with the outside air, is provided.

In the valve chamber 013, a valve 015 is supported from below by a support piece 017 projecting from a stop plate 016, and a weight 018, which is a sphere, is mounted on the valve 015.
Is placed.

A partition wall 019 is provided by projecting inward from the peripheral wall at a lower position of the same weight 018.
Is provided and a weight chamber 020 is formed in the upper part thereof.

Therefore, normally, in the state as shown in FIG. 2, the inside of the fuel tank is communicated with the outside air through the gap between the breather hole 014 and the weight 018 and the partition wall 019 to lower the internal pressure in the tank. There is.

When the fuel tank is tilted, the weight 018 rolls in the weight chamber 020 and moves on the inner wall slope of the weight chamber 020, so that the weight 018 moves away from the valve 015, so that the valve 015 removes the weight 018 placed on it. It is pressed toward the weight chamber 020 by the internal pressure in the tank or by being covered with fuel, and is pressed against the partition wall 019 to block the communication passage.

Therefore, the inside of the tank is sealed.

However, in the example shown in FIG. 2, although the fuel tank can be hermetically closed, the weight 018 dances on the valve 015 due to the vibration of the fuel tank 010, and an abnormal noise is generated. There was a problem with durability due to accelerated deterioration.

Further, in the case of a resin valve chamber, since it is difficult to assemble it, it is adopted as a valve unit via a rubber packing 021.

Therefore, the cost is high.

Further, when opening and closing the communication passage, all parts of the valve 015 must move the same distance, and in normal operation, one side of the valve 015 moves and then the other side moves.
Since it operates, it takes a long time to operate and response is poor.

Means and Actions for Solving Problems The present invention has been made in view of the above points, and an object of the present invention is to provide a rocking valve mechanism with excellent responsiveness of a flat plate and a resin cap body made of a resin. The point is to provide a cap that has a valve chamber and that can seal the tank with a lightweight and simple mechanism at a low cost.

That is, according to the present invention, in a cap that is attached to and detached from a fuel filling port of a vehicle fuel tank, a resin valve chamber is formed in a resin cap body, and the cap body and the valve chamber are connected to communicate with the outside air. A flat valve that forms a passage and opens and closes the communication passage is loosely fitted in the valve chamber, and a protrusion that is directed to one side of the valve is provided in the valve chamber to raise and lower one side of the valve. Is a narrower gap than other portions, and the valve is clamped by one side portion, and the valve is rocked around the clamping portion as a fulcrum to open and close the communication passage.

By using the valve mechanism, air can be sufficiently sucked into the fuel tank in normal times, and when the fuel tank is tilted, the valve can be quickly closed with good responsiveness and the tank can be sealed.

Since the valve chamber is made of the same resin as that of the cap body, the swelling ratio due to the fuel is equal, and therefore unequal deformation does not occur, and fuel leakage can be reliably prevented.

Further, since the valve chamber is made of the same resin as the cap body, the valve chamber can be formed as a part of the cap body, the number of parts can be reduced, and the weight and cost can be reduced.

Embodiment Hereinafter, an embodiment according to the present invention shown in FIGS. 3 to 6 will be described.

The embodiment is an example of a cap 1 used for a resin fuel tank of a motorcycle, and FIG. 3 shows a vertical sectional view of the cap 1.

The cap body 2 is made of a resin material, has an uneven knob portion 2a on the outer circumference, and has a screw portion 3 formed on the inner circumference of the inner cylindrical portion thereof.

Further, a cylindrical portion 4 is formed on the inner side thereof so as to project downward from the knob portion 2a, and an upper lid portion 2b covers the upper portion thereof.

A breather hole 5 is formed at the center of the lid 2b.

An inner cap 6 made of a disc resin is fitted to cover the lower end opening of the cylindrical portion 4 to form an inner chamber 7 together with the cylindrical portion 4 and the upper lid portion 2b.

A small hole 6e, which is a breather hole and a hole for removing fuel, is formed on the outer side portion of the inner cap 6.

A hole having a special shape is bored in the center of the inner cap 6, a sealing valve 9 is installed on the inner chamber 7 side, another inner cap 8 is installed on the outer side, and a primary valve 10 is loosely fitted inside.

The above members are mainly made of resin or rubber.

The structure of the central portion of the inner chamber is enlarged and shown in FIG.
The exploded perspective view is shown in FIG. 6, and a bottom view of the sealing valve 9 and a sectional view taken along line AA of the bottom view are shown in FIG.

The sealing valve 9 has an elongated cylindrical shape, and the inside thereof acts as a breather hole 9c.
In addition to the formation of a, a cross-shaped rib 9d is formed at the lower end of the breather hole 9C, and the rib 9d forms four communication spaces bordered by the edge and the inner peripheral edge of the breather hole 9c. Further, the lowermost edge 9b is projected downward with an acute angle.

The inner cap 6 has a slight bulge around the center hole, and a cylindrical upper layer space 20 having a small inner diameter and a cylindrical lower layer space 21 having a large inner diameter are formed in two layers on the back side thereof.

The upper wall partitioning the upper surface side portion of the upper layer space 20 projects from the outside to the inside to form a support portion 6a, and the groove 9a of the sealing valve 9 is fitted into the support portion 6a so that the sealing valve 9 can be secured. It is supposed to support.

Also, the lower layer space 21 formed on the back side of the inner cap 6
3 has a cylindrical protrusion 6b protruding downward from the upper lid.
It is formed in the place.

Further, the inner lower layer space 21 is further provided with notches 6c and locking portions 6d bent inwardly at three positions outside thereof.

The primary valve 10 has a disc shape whose diameter is somewhat smaller than the diameter of the cylindrical upper layer space 20 of the inner cap 6.

The inner cap 8 has a circular hole 8a in the center and has a disk shape with an outer diameter substantially equal to the diameter of the cylindrical lower layer space 21 of the inner chamber, and protrudes upward at four locations around the circular hole 8a on the upper surface thereof. Forming a boss 8c.

Only one of the bosses has a larger protrusion distance than the other bosses.

Further, a ring-shaped cutout 8d is formed on the outer periphery of the lower surface of the inner cap, three deep cutouts 8e are provided further toward the center, and a circle is formed through the cutout 8e and the upper surface of the inner cap. The hole 8b is bored,
The circular hole 8b is provided at a position corresponding to the column 6b formed in the inner space of the inner cap 6.

As described above, it is easy to combine the four members of the sealing valve 9, the inner cap 6, the primary valve 10, and the inner cap 8, and since they are mainly made of resin or rubber, they are slightly deformed. The sealing valve 9 is inserted from above through the central opening of the inner cap 6, and the groove 9a of the sealing valve is fitted into the support portion 6a of the inner cap 6.

Next, with the primary valve 10 loosely fitted in the inner upper layer space 20 of the inner cap 6, the inner cap 8 is fitted into the inner lower layer space 21 of the inner cap 6 from below.

At this time, the protrusion 6b formed on the inner cap 6 is inserted into the circular hole 8b formed on the inner cap 8, and the engaging portion 6d of the inner cap 6 is fitted on the lower surface of the inner cap 6 in the fitted state. The inner cap 8 is temporarily held by fitting into the notch 8d on the outer circumference.

Finally, the head of the protrusion 6b protruding downward through the circular hole 8b of the inner cap 8 is heated and melted to form caulking, so that the inner cap 8 is fixed to the inner cap 6.

In this way, the inner upper space 20 of the inner cap 6 becomes the valve chamber 20 with the sealing valve 9, the primary valve 10, and the inner cap 8 assembled in the inner cap 6, and the primary valve is loosely fitted in the valve chamber 20. It will be in a state of being.

The boss 8c projecting upward from the upper surface of the inner cap 8 in the same valve chamber 20 is located at a position vertically corresponding to the lowermost end 9b of the sealing valve 9, and the primary valve 10 is located between the two, and normally the primary valve 10 Is supported by its own weight on four bosses 8c in the front, rear, left and right (state shown in FIG. 4).

Therefore, the primary valve 10 is the inner cap 8
The circular hole 8a is not stuck to the circular hole 8a and the circular hole 8a communicates with the breather hole 9c of the sealing valve 9, and the valve is open.

When pressure is applied to the primary valve 10 from the lower side to the upper side, the primary valve 10 moves upward and the upper side portion of the primary valve 10 is pressed against the lowermost end 9b of the sealing valve 9 to open the lower end opening of the sealing valve 9. The valve can be closed by closing it.

Since only one of the four bosses 8c has a protruding portion with a large protruding distance, the gap distance X between the protruding portion and the lowermost end 9b of the upper sealing valve 9 is the other protruding portion and its upper portion. Is smaller than the gap distance Y from the lowermost end 9b of the ceiling valve 9, and therefore the up-and-down movement of the primary valve 10 shows a motion of swinging up and down around the portion of the primary valve 10 in a narrow gap as a fulcrum, and the opening and closing of the valve is smooth. To be done.

Generally, in the valve mechanism, if the valve opening is increased, the responsiveness at the time of closing is deteriorated, and if the valve opening is decreased, it causes a malfunction. However, in the case of this embodiment, the valve opening is appropriately maintained with the gap Y. , The primary valve can be swung in the gap X, and the responsiveness is improved.

Further, when the primary valve 10 closes the lower end opening of the sealing valve 9 and the tank internal pressure is still high, the primary valve 10 is deformed and its center projects toward the breather hole 9c side, but the cross shape formed inside the lower end of the sealing valve 9 The ribs 9d can prevent deformation beyond a certain level.

FIG. 4 shows a state in which the inner cap 6 having the above valve mechanism is attached to the lower end of the cylindrical portion 4 of the cap body 2.

A rubber packing 11 is fitted between the cylindrical portion 4 and the screw portion 3 at the shoulder portion of the knob portion 2a provided on the outer circumference.

With the cap 1 screwed onto the fuel filler port of the fuel tank and covered with the cap 1, the normal breather hole 5, the inner chamber 7, the breather hole 9c of the sealing valve 9 and the circular hole 8a of the inner cap 8 are provided.
And the small holes 6e of the inner cap 6 are all in communication with each other, so that air is sucked into the fuel tank from the outside and the fuel is smoothly supplied to the carburetor.

However, if the fuel tank tilts and the fuel in the tank covers the back side of the cap 1, the primary valve 10 swings due to the fuel or an increase in the internal pressure to immediately close the valve, and the breather of the sealing valve 9 is closed. Hole 9c
Can be closed.

As described above, in this embodiment, the primary valve 10 operates to seal the tank when the fuel tank is tilted. At this time, since the primary valve performs the swinging operation, the valve is immediately closed and the response is excellent.

Further, since the inner cap 6 that forms the valve chamber 20 is molded as a part of the cap body 2, it is not necessary to support it with a rubber seal or the like and a weight is not necessary, so that the number of parts can be reduced and the weight can be reduced.

Since the inner caps 6 and 8 are assembled by fitting, the clearance can be managed sufficiently, and since the three points are crimped, they have durability against vibration.

In the above-described embodiment, the sealing valve 9 has a long cylindrical shape, so that even if the fuel is accumulated in the inner chamber 7 to some extent, the breather hole 9c can be communicated with the upper space of the fuel tank to communicate with the atmosphere. The hole 6e was improved so that the fuel accumulated in the inner chamber 7 could be drained in a short time. However, when this is not necessary, the sealing valve 9 does not need to be a long cylinder, and its deformation An example is shown in FIG.

In this embodiment, the two inner caps 6 and 8 in the previous embodiment are integrally formed into an inner cap 30, and a peripheral wall of a central circular hole 30a thereof is slightly projected upward to form a cylindrical portion 30b, and a groove 30c is formed on the outer periphery thereof. Is formed.

The sealing valve 31 is fitted so as to cover the cylindrical portion 30b of the inner cap 30 from above.

The sealing valve 31 has a circular hole 31a which is a breather hole in the center.
The lower end portion 31b of the peripheral wall is formed at an acute angle, a groove 31c is formed in a ring shape on the circumference of the lower surface, and a protrusion 31e is formed on the inner peripheral surface of the outer portion 31d. .

Therefore, the cylindrical portion 30b of the inner cap 30 is fitted into the groove 31c of the sealing valve 31, and the groove 30c formed on the outer periphery of the cylindrical portion 30b and the ridge 31e formed on the inner peripheral surface of the outer portion 31d of the sealing valve 31. The sealing valve 31 is firmly fixed to the inner cap 30 by fitting.

In this manner, the valve chamber 32 is formed in the center in the state where the inner cap 30 and the sealing valve 31 are combined.
The primary valve 33 is loosely fitted in the 32.

The above members are mainly made of resin or rubber.

In the valve chamber 32, as in the previous embodiment, four bosses 30d are provided so as to project upward from the circumference of the circular hole 30a of the inner cap 30, and one of the bosses is formed longer than the other bosses. The vertical movement of the primary valve 33 is used as a swinging movement to smooth the valve operation.

In this embodiment as well, the same effect as the above embodiment can be obtained, but it takes a little longer than the above embodiment to drain the fuel accumulated in the inner chamber.

In addition to the above embodiment, as shown in FIG. 8, a notch 9e may be provided in the cylindrical portion of the sealing valve 9 shown in FIGS.

Various other configurations of the valve mechanism are possible.

Effect of the Invention In the present invention, the valve operation is an oscillating motion, and the valve opening can be appropriately maintained to provide excellent responsiveness.

Further, since the valve chamber is formed of the same resin member as the cap body, the tank can be reliably sealed.

Further, since the cap body and the member forming the valve chamber are both made of resin, the valve chamber can be formed as a part of the cap body, the number of parts can be reduced, and the weight and cost can be reduced.

In addition, processing such as welding is easy.

[Brief description of drawings]

FIG. 1 is a side view of a conventional fuel tank and a cap showing a partial cross section, FIG. 2 is a vertical cross section of the cap of the same example, and FIG. 3 is a vertical cross section of a cap of one embodiment according to the present invention. 4 and 5 are a longitudinal sectional view of the inner cap portion of the embodiment, FIG. 5 is a bottom view of the sealing valve and a sectional view taken along line AA in the bottom view, and FIG. 6 is an exploded perspective view of the inner cap. FIG. 7 is a longitudinal sectional view of an inner cap portion in another embodiment, and FIG. 8 is a perspective view of a sealing valve in yet another embodiment. 1 ... Cap, 2 ... Cap body, 2a ... Knob part, 2
b ... Top cover part, 3 ... Screw part, 4 ... Cylindrical part, 5 ... Breather hole, 6 ... Inner cap, 6a ... Support part, 6b ... Projection, 6c ... Notch, 6d ... Locking part, 6e ... Small hole, 7 ... inner chamber, 8 ... inner cap, 8a ... circular hole, 8b ... circular hole,
8c ... Boss, 8d, 8e ... Notch, 9 ... Sealing valve, 9a ... Groove, 9b ... Bottom edge, 9c ... Breather hole, 9
d ... Rib, 10 ... Primary valve, 20 ... Upper layer space, 21 ... Lower layer space, 30 ... Inner cap, 30a ... Circular hole, 30b ... Cylindrical part, 30c ... Groove, 31 ... Sealing valve, 31a ... Circular hole, 31b ... Lower end of peripheral wall, 31c ... Groove, 31
d ... Outer part, 31e ... Ridge, 32 ... Valve chamber, 33 ... Primary valve.

Claims (1)

[Scope of utility model registration request] 1. A cap which is attached to and detached from a fuel filler port of a vehicle fuel tank, wherein a resin valve chamber is formed in a resin cap body, and the cap body and the valve chamber communicate with the outside air in the fuel tank. A flat valve that forms a passage and opens and closes the communication passage is loosely fitted in the valve chamber, and a protrusion that is directed to one side of the valve is provided in the valve chamber to raise and lower one side of the valve. The cap of the fuel tank for vehicles is characterized in that the gap is narrower than that of the other part, and the valve is clamped at one side, and the valve is oscillated around the clamping part to open and close the communication passage. .