JP2017159822A - Fuel cap with breather mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cap with a breather mechanism capable of suppressing sound squeak from occurring when discharging fuel vapor, and also capable of suppressing an increase in cost and the enlargement thereof.SOLUTION: A fuel cap with a breather mechanism is a cap that openably closes an oil supply port of a fuel tank T, and comprises a breather passage 20 that communicates the inside of the fuel tank T with the atmosphere A, and a valve 30 provided at the breather passage 20. The valve 30 includes a bearing surface 27 and a valve port 28 provided in the breather passage 20, a valve body 31 that closes/opens the valve port 28 by coming into contact with, and separating from the bearing surface 27, and a spring for bringing the valve body 31 into contact with the bearing surface 27 until the inner pressure of the fuel tank T becomes or exceeds a predetermined pressure. As viewed from an opening/closing direction of the valve body 31, a recess 29, which recesses toward a direction opposite to the opening direction of the valve body 31, is provided around the bearing surface 27.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fuel cap with a breather mechanism.

  2. Description of the Related Art Conventionally, as seen in, for example, Patent Document 1, a cap (60) that closes an oil supply opening (16a) of a fuel tank (16) so as to be openable and closable. A passage (80), and a valve (91) provided in the breather passage (80). The valve (91) includes a seat surface and a valve port (101) provided in the breather passage (80). The valve body (103) that opens and closes the valve port (101) by being in contact with the seating surface and the valve body (103) until the internal pressure of the fuel tank (16) becomes a predetermined pressure or more. A fuel cap with a breather mechanism having a spring (111) to be brought into contact with the seat surface is known.

  According to such a fuel cap (60) with a breather mechanism, the valve port (101) opens only when the internal pressure of the fuel tank (16) becomes a predetermined pressure or higher, and the fuel tank (16 ) Is discharged to the atmosphere, so that the diffusion of the fuel vapor to the atmosphere can be suppressed.

  On the other hand, according to the fuel cap with a breather mechanism as described above, if no measures are taken, an exhaust sound (sound) may be generated when the valve port is opened and exhaust is performed. There is a difficulty.

  Therefore, the conventional fuel cap (60) with a breather mechanism described above has been designed to prevent noise by providing a resonator chamber (81) as a silencer mechanism in the breather passage (80).

Japanese Patent No. 5771651

  In the conventional fuel cap (60) with a breather mechanism described above, the resonator chamber (81) is provided in the breather passage (80) in order to prevent noise. Therefore, the structure is complicated, resulting in an increase in cost and a large cap. Was inviting.

  The problem to be solved by the present invention is to provide a fuel cap with a breather mechanism capable of suppressing noise generation at the time of discharging fuel vapor and suppressing cost increase and enlargement.

In order to solve the above problems, a fuel cap with a breather mechanism of the present invention is
A cap for opening and closing a fuel tank refueling port, comprising a breather passage communicating the inside of the fuel tank and the atmosphere, and a valve provided in the breather passage;
The valve has a seat surface and a valve port provided in the breather passage, a valve body that opens and closes the valve port by being in contact with and separated from the seat surface, and the valve body has a predetermined internal pressure of the fuel tank. In a fuel cap with a breather mechanism having a spring that abuts against the seat surface until the pressure is exceeded,
As viewed from the opening / closing direction of the valve body, a recess is provided around the seat surface to be recessed in the direction opposite to the opening direction of the valve body.
According to this fuel cap with a breather mechanism, the valve body moves and the valve port opens only when the internal pressure of the fuel tank becomes equal to or higher than a predetermined pressure, and the gas (fuel vapor) in the fuel tank passes through the breather passage to the atmosphere. Therefore, the diffusion of fuel vapor to the atmosphere can be suppressed.
Further, according to the fuel cap with a breather mechanism, since the recess is provided around the seat surface in a direction opposite to the opening direction of the valve body when viewed from the opening / closing direction of the valve body. The fuel vapor flowing out from the valve port to the breather passage through the gap between the valve body and the seat surface also flows into the recess. This flow of fuel vapor into the recess acts to reduce the maximum pressure amplitude of the fuel vapor, so that exhaust noise (sounding) is suppressed.
In addition, this fuel cap with a breather mechanism can be configured by providing a recess recessed in the direction opposite to the opening direction of the valve body around the seat surface when viewed from the opening and closing direction of the valve body. Can be suppressed.
As described above, according to the fuel cap with the breather mechanism, it is possible to suppress the noise when the fuel vapor is discharged, and to suppress the increase in cost and size.

In this fuel cap with breather mechanism,
The seating surface may be formed integrally with the breather passage, and the recess may have a wide opening near the seating surface and become narrower as it moves away from the seating surface in a direction opposite to the valve body opening direction. .
If comprised in this way, since it becomes easy to create a recessed part, a cost increase can be suppressed further.

In this fuel cap with breather mechanism,
The seat surface is composed of a ring-shaped member separate from the breather passage, and the ring-shaped member is formed so that the recess is formed around the ring-shaped member when viewed from the opening / closing direction of the valve body. It can be set as the structure currently fixed to the breather channel | path.
If comprised in this way, since the said recessed part can be formed with a ring-shaped member separate from a breather channel | path, creation of a recessed part can be facilitated and cost increase can be suppressed further.

It is a figure which shows embodiment of the fuel cap with a breather mechanism which concerns on this invention, (a) is sectional drawing, (b) is the elements on larger scale of figure (a). (A) is 2-2 sectional drawing in FIG.1 (b), (b) is a figure which shows a modification. Action explanatory drawing. The figure which shows other embodiment. The figure which shows further another embodiment. The elements on larger scale of Fig.1 (a). FIG. 14 is a view showing still another embodiment, in which (a) is a partially omitted plan view, and (b) is a longitudinal sectional view (a view corresponding to a cross section taken along a dashed line bb in FIG. (A)).

  Embodiments of a fuel cap with a breather mechanism according to the present invention will be described below with reference to the drawings. In each figure, the same reference numerals are given to the same or corresponding parts.

  As shown in FIG. 1, a fuel cap 10 with a breather mechanism according to this embodiment is a cap that opens and closes a fuel filler port T1 of a fuel tank T, and a breather that communicates the inside T3 of the fuel tank T with the atmosphere A. A passage 20 and a valve (positive pressure valve; the same applies hereinafter) 30 provided in the breather passage 20 are provided.

  The fuel cap 10 includes a lower body 11, an upper body 12 attached to the lower body 11 from above, and a cover 13 attached to the lower body 11 and the upper body 12 from above.

A seal member 14 is provided between the lower body 11 and the upper body 12, and a ring-shaped holding member 15 that holds the edge portion 14 b of the seal member 14 on the edge portion 12 b of the upper body 12 serves as the edge portion 12 b of the upper body 12. And the edge 13 b of the cover 13.
The central ring portion 14c of the seal member 14 constitutes a cap seal that comes into contact with the fuel filler port T1 when the fuel cap 10 is closed.

When the fuel cap 10 is closed, the breather passage 20 has an appropriate configuration as long as one end opens to the inside T3 of the fuel tank T and the other end opens to the atmosphere A through the valve 30. obtain.
In this embodiment, one end 21 of the breather passage 20 is configured as a lower opening of the lower body 11, and the other end 26 is an upper passage 22 provided on the upper portion of the lower body 11 through the valve 30 from the one end 21, It opens to the lower surface of the fuel cap 10 through the communication passages 23, 24 and 25.

A breather seal 16 is provided between the upper portion of the upper body 12 and the cover 13, and the upper passage 22 is formed by the upper portion of the upper body 12 and the breather seal 16.
The communication passage 23 is formed by a groove and a breather seal 16 that are partially provided in the upper body 12 in the circumferential direction.
The communication path 24 is formed by the upper surface of the upper body 12 and the inner surface of the cover 13.
The communication path 25 is formed by an inner surface of the cylindrical side wall of the cover 13 and a groove partially provided in the circumferential direction on the outer side of the upper body 12 and the ring-shaped holding member 15.
The lower end of the communication passage 25 forms the other end 26 of the breather passage 20 and is open to the atmosphere A.

  The valve 30 includes a seat surface 27 and a valve port 28 provided in the breather passage 20, a valve body 31 that opens and closes the valve port 28 by being in contact with the seat surface 27, and this valve body 31 is connected to the fuel tank T And a spring 32 that is brought into contact with the seating surface 27 until the internal pressure Pt becomes a predetermined pressure or higher.

  As shown in FIG. 2, a concave portion 29 is provided around the seat surface 27 when viewed from the opening / closing direction of the valve body 31. The recess 29 is recessed in the direction opposite to the opening direction of the valve body 31.

  According to this fuel cap with a breather mechanism, the valve body 31 moves as shown in FIG. 3 to open the valve port 28 only when the internal pressure Pt of the fuel tank T becomes equal to or higher than a predetermined pressure. Since the fuel vapor G in the fuel tank T is discharged to the atmosphere A, the diffusion of the fuel vapor to the atmosphere A can be suppressed.

And according to this fuel cap 10 with a breather mechanism, the recessed part which dents toward the direction opposite to the opening direction of the valve body 31 (downward in FIG. 1) around the seat surface 27 seeing from the opening / closing direction of the valve body 31. 29, the fuel vapor G flowing out from the valve port 28 to the breather passage 20 through the gap C1 between the valve body 31 and the seat surface 27 is opened as shown in FIG. As shown by the arrow G2, it will also flow into the recess 29. Since the flow (G2) of the fuel vapor G into the concave portion 29 acts to reduce the maximum pressure amplitude of the fuel vapor G, the exhaust sound (sounding) is suppressed.
Further, the fuel cap 10 with the breather mechanism can be configured by providing a recess 29 that is recessed in the direction opposite to the opening direction of the valve body 31 around the seat surface 27 when viewed from the opening / closing direction of the valve body 31. , Cost increase and increase in size can be suppressed.
As described above, according to the fuel cap with the breather mechanism, it is possible to suppress the noise when the fuel vapor is discharged, and to suppress the increase in cost and size.

In FIG. 3, G <b> 1 indicates fuel vapor that flows toward the upper passage 22 without flowing into the recess 29. The other fuel vapor G2 flows into the recess 29 and then travels to the upper passage 22.
The illustrated valve body 31 has a valve seal 31 s, and this valve seal 31 s comes into contact with and separates from the seat surface 27.
The spring 32 is a coil spring and is press-fitted between the spring receiving portion 31 b of the valve body 31 and the breather seal 16.

  The concave portion 29 shown in FIG. 2A has a ring shape when viewed from the moving direction of the valve body 31, but the concave portion 29 may be divided in the circumferential direction as shown in FIG. 2B, for example. In FIG. 2 (b), it is divided into two, but it is possible to make it into three or more. It is only necessary to reduce the maximum pressure amplitude of the fuel vapor G so that the exhaust sound (sound) does not matter.

The seating surface 27 is formed by the inner wall surface of the breather passage 20 itself. That is, the seat surface 27 is formed integrally with the breather passage 20.
As shown in FIG. 4, the recess 29 has a wide opening 29 b near the seating surface 27, and becomes narrower as it moves away from the seating surface 27 in the direction opposite to the opening direction of the valve body 31 (downward in the drawing). Can do.
If comprised in this way, since it becomes easy to produce the recessed part 29, a cost increase can be suppressed further.

As shown in FIG. 5, the seat surface 27 is composed of a ring-shaped member 40 that is separate from the breather passage 20, and a recess 29 is formed around the ring-shaped member 40 when viewed from the opening / closing direction of the valve body 31. Thus, the ring-shaped member 40 can be configured to be fixed to the breather passage 20.
If comprised in this way, since the recessed part 29 can be formed with the ring-shaped member 40 separate from the breather channel | path 20, creation of the recessed part 29 can be made easy and cost increase can be suppressed further.

  The ring-shaped member 40 has a ring-shaped base portion 41 that forms a ring-shaped seating surface 27 on the upper surface, and a cylindrical portion 42 with an external thread that is formed integrally with the base portion 41. Is fixed in the breather passage 20 by screwing with a female screw portion 20 s formed on the inner wall surface of the breather passage 20.

In FIG. 1, 50 is a negative pressure valve.
The negative pressure valve 50 opens when the internal pressure Pt of the fuel tank T becomes a predetermined pressure difference or less with respect to the atmospheric pressure, and guides the atmosphere into the fuel tank T.
As shown in FIG. 6, the negative pressure valve 50 is separated from and abutted on the seat surface 57 and the seat surface 57 and the valve port 58 provided in the negative pressure breather passage 20 n communicating with the breather passage 20 described above. The valve body 51 that opens and closes the valve port 58 and a spring (coil spring) that makes the valve body 51 contact the seat surface 57 until the internal pressure Pt of the fuel tank T becomes equal to or less than a predetermined pressure difference with respect to the atmospheric pressure. 52.
A spring receiving portion 53 is attached to the upper body 12, and a coil spring 52 is press-fitted between the spring receiving portion 53 and the valve body 51.

  7A and 7B are diagrams showing still another embodiment, in which FIG. 7A is a plan view in which the cover 13 and the breather seal 16 are omitted, and FIG. 7B is a longitudinal sectional view (a dashed line b-- in FIG. 7A). (a figure corresponding to the cross section along b).

  This embodiment is mainly different from the above-described embodiment in that the breather passage 20a on the upstream side of the valve 30 opens into the inside T3 of the fuel tank T through the orifice 20b, and the breather passage on the downstream side of the valve 30. 20c opens to the atmosphere A on the lower surface of the fuel cap 10 through the orifice 20d, the inner annular flow path 20e, the atmosphere-side flow path 20f of the negative pressure valve 50, the outer annular flow path 20g, and the communication paths 20h and 25. There are no major changes in other points.

A breather passage 20 a and an orifice 20 b on the upstream side of the valve 30 are formed in the upper body 12.
The breather passage 20 c on the downstream side of the valve 30 is formed by the upper part of the upper body 12 and the breather seal 16.
The orifice 20d is formed in the upper body 12.
The inner annular flow path 20e is formed by the upper part of the upper body 12 and the breather seal 16, and communicates the orifice 20d and the atmosphere-side flow path 20f of the negative pressure valve 50.
The atmosphere side flow path 20 f of the negative pressure valve 50 is formed by the upper part of the upper body 12 and the breather seal 16.
The outer annular flow paths 20 g and 20 h are formed by the upper surface of the upper body 12 and the inner surface of the cover 13.
The communication path 25 is formed by an inner surface of the cylindrical side wall of the cover 13 and a groove partially provided in the circumferential direction on the outer side of the upper body 12 and the ring-shaped holding member 15.
The lower end of the communication passage 25 forms the other end 26 of the breather passage 20 and is open to the atmosphere A.
In FIG. 7A, reference numeral 17 denotes a lock key cylinder.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be appropriately modified within the scope of the gist of the present invention.

  A: Atmosphere, T: Fuel tank, T1: Refueling port, T3: Inside of fuel tank T, 10: Fuel cap with breather mechanism, 20: Breather passage, 27: Seat surface, 28: Valve port, 29: Recess, 30 : Valve 30, 31: valve body, 32: spring, 40: ring-shaped member.

Claims (3)

A breather passage (20) for closing the fuel filler opening (T1) of the fuel tank (T) so as to be openable and closable, and communicating the inside (T3) of the fuel tank (T) with the atmosphere (A), and the breather passage A valve (30) provided in (20),
This valve (30) opens and closes the valve port (28) by being in contact with and separated from the seat surface (27) and the valve port (28) provided in the breather passage (20). And a spring (32) that causes the valve body (31) to abut against the seat surface (27) until the internal pressure of the fuel tank (T) becomes a predetermined pressure or higher. In the fuel cap with mechanism,
A recess (29) is provided around the seat surface (27) when viewed from the opening and closing direction of the valve body (31). The recess (29) is recessed in the direction opposite to the opening direction of the valve body (31). A fuel cap with a breather mechanism. In claim 1,
The seat surface (27) is formed integrally with the breather passage (20), and the recess (29) has a wide opening (29b) near the seat surface (27), and the opening direction of the valve body (31). A fuel cap with a breather mechanism, which narrows as it moves away from the seating surface (27) in the opposite direction. In claim 1,
The seat surface (27) is composed of a ring-shaped member (40) separate from the breather passage (20), and is seen around the ring-shaped member (40) when viewed from the opening / closing direction of the valve body 31. The fuel cap with a breather mechanism, wherein the ring-shaped member (40) is fixed to the breather passage (20) so that a recess (29) is formed.

Images