JPH10329557A - Liquid fuel tank cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the unnecessary releasing of vapor of liquid fuel contained in a tank through a pressure releasing hole so as to suppress the resultant contamination of air by eliminating the lowering of the valve opening pressure of a pressure releasing valve which may occur due to a valve element being caught. SOLUTION: A liquid fuel tank cap is structured so that an annular part 9 surrounding the opening part 5 for pressure releasing hole 4 is raised from the inner bottom surface 8 of a valve element storing part 2, the rise end surface of the annular part 9 is used as a valve seat 6, a protruded line 11 is raised from the inner bottom surface 8 of the valve element storing part 2 at a position apart from the annular part 9, and the rise end surface of the protruded line 11 is used as a pivot part 12. Also a valve element 7 is put on the valve seat 6 and pivot part 12, pressed against the valve seat 6 and pivot part 12 by magnet, and the pivot part 12 is used as a pivot so as to raise the valve element 7 from the valve seat 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cap for a liquid fuel tank.

[0002]

2. Description of the Related Art FIG. 5 shows a prior art of a liquid fuel tank cap. This is performed as follows, as in the present invention. That is, as shown in FIG. 5A, a pressure release hole 104 communicating with the inside of the tank 103 is formed in the inner bottom of the valve body accommodating portion 102 of the pressure release valve 101, and a valve is formed in the opening 105 of the pressure release hole 104. A seat 106 is provided, and a valve body 107 is seated on the valve seat 106. When the internal pressure of the tank 103 exceeds a predetermined value, the valve body 107 is moved by the internal pressure.
And the internal pressure of the tank 103 is increased
Through to the atmosphere.

[0003] This prior art differs from the present invention in the following points. That is, in this prior art, as shown in FIG. 5B, the valve seat 106 of the pressure release valve 101 is formed with a tapered surface.
A ball valve element 107 is seated on the valve seat 106, and a spring receiving recess 116 is disposed at a position facing the valve seat 106, and one end 1 of a valve spring 117 is placed in the spring receiving recess 116.
18 is fitted therein, and the valve body 107 is
Is pressed against the valve seat 106.

[0004]

The above prior art has the following problems. In the prior art, as shown in FIG. 5B, the valve spring 11 is inserted into the spring receiving recess 116 of the pressure release valve 101.
7, one end 118 of the valve spring 117 is caught on the inner peripheral surface 115 of the spring receiving recess 116, and the valve opening pressure of the pressure release valve 101 becomes lower than the set value. is there. In this case, the vapor of the liquid fuel in the tank 103 unnecessarily escapes from the pressure release hole 104, and the air is polluted.

The object of the first invention is as follows. To prevent a decrease in the valve opening pressure of the pressure relief valve. Maintaining high sealing performance of the pressure relief valve. The object of the second invention is as follows in addition to the object of the first invention. To suppress the change of the set value of the valve opening pressure due to the shift of the fulcrum. The subject of the third invention is:
In addition to the problem of the second invention, the following points are provided. To further increase the sealing force of the pressure relief valve.

[0006]

[Means for Solving the Problems]

(First Invention) In the first invention, as shown in FIG. 3, a pressure release hole 4 communicating with the inside of the tank 3 is formed in the inner bottom of the valve body accommodating portion 2 of the pressure release valve 1, and FIG. As shown in FIG.
A valve seat 6 is provided in the opening 5 of the tank 3, and a valve body 7 is seated on the valve seat 6. When the internal pressure of the tank 3 exceeds a predetermined value, as shown in FIG. Is raised from the valve seat 6 so that the internal pressure of the tank 3 is released to the atmosphere. The liquid fuel tank cap is characterized as follows.

That is, as shown in FIG. 1 (A), a ring 9 surrounding the opening 5 of the pressure release hole 4 is raised from the inner bottom surface 8 of the valve housing 2, and the rising end face of the ring 9 is raised. Is a valve seat 6, and at a position away from the ring portion 9, a ridge 11 is raised from the inner bottom surface 8 of the valve body housing 2, and a rising end face of the ridge 11 is a fulcrum portion 12, 6 and the fulcrum part 12, the valve body 7 is mounted on the valve body 6 and the fulcrum part 1 by magnetic force.
2, and as shown in FIG.
The valve body 7 is lifted from the valve seat 6 with the fulcrum as a fulcrum.

(Second Invention) In a second invention, as shown in FIG. 1C, in the first invention, the central axis 1 of the pressure relief hole 4 is provided.
3, the fulcrum portion 12 is formed in an arc shape centered on the central axis 13 of the pressure release hole 4 when viewed in a direction parallel to 3.

(Third Invention) According to a third invention, as shown in FIG. 1C, in the second invention, both ends 14 of the ridge 11 forming the fulcrum 12 are extended to accommodate the valve body. It is characterized in that it is connected to the inner peripheral surface 15 of the part 2.

[0010]

Actions and effects of the present invention

(First Invention) The first invention has the following effects. First
In the present invention, as shown in FIGS. 1A and 1B, the valve body 7 is placed on the valve seat 6 and the fulcrum part 12, and the valve body 7 is pressed against the valve seat 6 and the fulcrum part 12 by magnetic force. Since the valve element 7 is lifted from the valve seat 6 with the fulcrum portion 12 as a fulcrum, there is no possibility that the valve opening pressure of the pressure release valve 1 is reduced due to the catch of a valve spring or the like. For this reason, the vapor of the liquid fuel in the tank 3 does not unnecessarily escape from the depressurizing hole 4, thereby preventing the air from being polluted.

In the first invention, as shown in FIGS. 1A and 1B, the rising end face of the ring portion 9 is used as the valve seat 6 and the ridge 11 is formed.
Of the valve seat 6 and the fulcrum 12 are relatively small. For this reason, when the valve element 7 is mounted on the valve seat 6 and the fulcrum part 12 and the valve element 7 is pressed against the valve seat 6 and the fulcrum part 12 by magnetic force, the contact surface between the valve element 7 and the valve seat 6 is obtained. , The pressure per unit area increases, and the sealing force of the pressure relief valve 1 increases.

(Second invention) The second invention has the following functions and effects in addition to the functions and effects of the first invention. In the second invention, as shown in FIG. 1C, since the fulcrum portion 12 is formed in an arc shape centered on the central axis 13 of the pressure release hole 4, the fulcrum portion 12 is substantially equal to the central axis 13 of the pressure release hole 4. , The valve body 7 is lifted with any point of the fulcrum portion 12 as a fulcrum, so that a change in the set value of the valve opening pressure of the pressure release valve 1 due to the misalignment of the fulcrum can be suppressed.

(Third invention) The third invention has the following operation and effect in addition to the operation and effect of the second invention. In the third invention, as shown in FIG. 1C, the ridge 11 forming the fulcrum 12
Are extended and connected to the inner peripheral surface 15 of the valve housing 2, the vibration of the ridge 11 is suppressed, the vibration of the valve 7 is suppressed, and the pressure relief valve 1 Sealing power is further increased.

[0014]

Embodiments of the present invention will be described with reference to the drawings. 1 to 3 are diagrams for explaining an embodiment of the present invention. In this embodiment, a cap for a liquid fuel tank of an engine is used. As shown in FIG. 3, the tank 3 is provided with a fuel supply cylinder 19,
A cap 21 is attached to the upper end opening 20 of the camera.

The structure of the fuel supply cylinder 19 is as follows.
The fuel supply cylinder 19 has a cylindrical shape, and is provided with an inwardly folded cap mounting portion 22 at an upper end opening 20 thereof. FIG.
As shown in (B), an insertion port 25 is formed from the upper wall 23 to the inner wall 24 of the cap mounting portion 22, and the inner wall 2 is formed.
4, a guide part 26 and an engaging part 27 which follow the insertion port 25 are formed.

The structure of the cap 21 is as follows. As shown in FIG. 3, a plate spring engaging piece 29 and a baffle plate 30 are provided at a lower portion of a dish-shaped cap body 28 with the opening facing upward.
And a dish-shaped handle 31 with an opening facing downward is provided at the upper part of the cap body 28. As shown in FIG. 4 (A), a bulging fingerhold 38 is formed around the handle 31. As shown in FIG. 3, the inside of the cap body 28 is hollow, and the breather device 32 is fitted and fixed therein. The leaf spring engaging piece 2 is provided on the bottom plate 33 of the cap body 28.
9 is opened, and the first communication port 3 is opened.
4 communicates the inside of the tank 3 with the inside of the cap body 28.

As shown in FIG. 3, a flange 35 is formed on the cap body 28, and as shown in FIG. 4A, an arc-shaped ridge 36 is formed on the flange 35 along the circumferential direction thereof.
And the handle 31 is attached to the ridge 36 as shown in FIG.
4A, the ceiling 37 is placed and fixed, and as shown in FIG. 4 (A), the protruding ridge 36 is divided at a position facing the fingerhold 38, so that the divided portion becomes the second communication port 39. As shown in (2), the breather device 32 communicates with the atmosphere through the second communication port 39. An annular gasket 40 is mounted below the flange 35.

As shown in FIG. 3, the cap 21 is mounted on the fuel supply cylinder 19 as follows. Cap 21
Is placed on the cap mounting portion 22, and the leaf spring engaging piece 29 is inserted from above into the insertion opening 25 of the cap mounting portion 22 as shown by an arrow in FIG. The guide portion 26 guides the locking portion 27
To be engaged. Thereby, as shown in FIG. 3, the cap 21 is mounted on the cap mounting portion 22. The gasket 40 is in close contact with the upper wall 23 of the cap mounting section 22, and the cap mounting section 22 and the cap 21 are sealed. When the leaf spring engaging piece 29 is engaged with the locking portion 27, the leaf spring engaging piece 29 separates from the first communication port 34 and the first communication port 3
4 opens.

The structure of the breather device 32 is as follows. A pressure relief valve mounting recess 42 and an intake valve mounting recess 43 are formed in a disc-shaped valve holder 41, the pressure relief valve 1 is mounted in the pressure relief valve mounting recess 42, and the intake valve 4 is mounted in the intake valve mounting recess 43.
4 is attached. The valve holder 41 is made of rubber. The opening of the pressure relief valve mounting concave portion 42 is downward, and the opening of the intake valve mounting concave portion 43 is upward. A pressure relief valve outlet 45 is provided on the ceiling of the pressure relief valve mounting recess 42, and an intake valve outlet 46 is provided on the bottom plate of the intake valve mounting recess 43.

The structure of the pressure relief valve 1 is as follows. A pressure release hole 4 communicating with the inside of the tank 3 is formed in the inner bottom of the valve body accommodating portion 2 of the pressure release valve 1, and a valve seat 6 is formed in an opening 5 of the pressure release hole 4 as shown in FIG. When the internal pressure of the tank 3 exceeds a predetermined value as shown in FIG. 1 (B), the valve element 7 is lifted from the valve seat 6 by the internal pressure, and The internal pressure 3 is released to the atmosphere through the pressure release hole 4.

As shown in FIG. 1 (A), an annular portion 9 surrounding the opening 5 of the pressure release hole 4 is raised from the inner bottom surface 8 of the valve body accommodating portion 2, and the rising end surface of the annular portion 9 is valved. The ridge 11 is raised from the inner bottom surface 8 of the valve body housing 2 at a position away from the ring portion 9, and the rising end surface of the ridge 11 is defined as a fulcrum portion 12, and The valve 7 is placed on the fulcrum 12 and the valve 7 is pressed against the valve seat 6 and the fulcrum 12 by magnetic force. As shown in FIG. It is lifted from the valve seat 6.

The valve body accommodating portion 2 is formed by forming a disc-shaped rubber valve body accommodating plate 47 at a central portion thereof in a circular concave shape. The opening of the valve housing 2 is upward. The ring portion 9 is made of rubber and has a ring shape and protrudes from the inner bottom surface 8 of the valve body housing portion 2. The valve seat 6 is also annular. The valve body housing plate 47 is
It is fixed in a dish-shaped iron holding plate holder 10. The opening of the storage plate holder 10 is upward. Valve element 7
Is formed by a disk-shaped magnet.

As shown in FIG. 1C, the fulcrum 12 is formed in an arc shape centered on the central axis 13 of the pressure relief hole 4 when viewed in a direction parallel to the central axis 13 of the pressure relief hole 4. It is.
Further, both end portions 14 of the ridge 11 forming the fulcrum portion 12 are extended and connected to the inner peripheral surface 15 of the valve body housing portion 2. The ridge 11 is made of rubber and protruded from the inner bottom surface 8 of the valve body housing 2.

As shown in FIG. 3, the structure of the intake valve 44 is as follows. An intake hole 54 communicating with the atmosphere is opened in the ceiling of the valve body accommodating portion 52 of the intake valve 44, and a valve seat 56 is provided in an opening 55 of the intake hole 54 as shown in FIG.
When the valve body 57 is seated on the valve seat 56 and the internal pressure of the tank 3 becomes a negative pressure as shown in FIG. 2 (B), the valve body 57 is lifted from the valve seat 56 at atmospheric pressure, and the outside air is introduced into the intake hole 54. Through the tank 3.

As shown in FIG. 2A, the valve housing 52
An annular portion 59 surrounding the opening 55 of the intake hole 54 is raised from an inner bottom surface 58 of the valve body, and a rising end face of the annular portion 59 is used as a valve seat 56. A ridge 61 is set up from the inner bottom surface 58 of the
The rising end face of the valve member 1 is used as a fulcrum portion 62, and a valve body 57 is placed on the valve seat 56 and the fulcrum portion 62, and the valve body 57 is pressed against the valve seat 56 and the fulcrum portion 62 by magnetic force. As shown in ()), the valve body 57 is lifted from the valve seat 56 with the fulcrum 62 as a fulcrum. According to such a configuration,
Since the total area of the valve seat 56 and the fulcrum 62 is relatively small, the pressure per unit volume of the contact surface between the valve body 57 and the valve seat 56 increases, and the sealing force of the intake valve 44 increases. Therefore, the vapor of the liquid fuel in the tank 3 does not unnecessarily escape from the intake valve 44, and the resulting air pollution is prevented.

The valve body accommodating portion 52 is formed by forming a disc-shaped rubber valve body accommodating plate 67 at a central portion thereof in a circular concave shape. The opening of the valve housing 52 is downward. Ring part 59
Is made of rubber and has an annular shape and protrudes from the inner bottom surface 58 of the valve element accommodating portion 52. The valve seat 56 is also annular. The valve body housing plate 67 is fitted and fixed in a dish-shaped iron housing plate holder 60. The opening of the storage plate holder 60 is directed downward. The valve body 57 is formed of a disk-shaped magnet.

As shown in FIG. 2C, the fulcrum 62 is formed in an arc shape centered on the central axis 63 of the pressure release hole 54 when viewed in a direction parallel to the central axis 63 of the intake hole 54. is there. For this reason, the valve body 57 is lifted with any point of the fulcrum portion 62 located at a substantially equal distance from the center axis 63 of the intake hole 54 as a fulcrum, and the displacement of the fulcrum sets the valve opening pressure of the intake valve 44. The value can be prevented from changing. Further, both ends 64 of the ridge 61 forming the fulcrum 62
Is connected to the inner peripheral surface 65 of the valve body accommodating portion 52. Therefore, the vibration of the ridge 61 is suppressed, so that the vibration of the valve body 57 is suppressed, and the sealing force of the intake valve 54 is further increased. The radius of the fulcrum portion 62 formed in an arc shape is smaller than the radius of the fulcrum portion 12 of the pressure relief valve 1. Therefore, the set value of the valve opening pressure of the intake valve 44 becomes smaller than the set value of the valve opening pressure of the pressure release valve 1.

[Brief description of the drawings]

FIG. 1 is a view for explaining a pressure relief valve used in an embodiment of the present invention. FIG. 1 (A) is a longitudinal sectional view in a closed state, FIG. 1 (B) is a longitudinal sectional view in an open state, FIG. (C) is the CC of FIG.
It is a line sectional view.

2A and 2B are diagrams illustrating an intake valve used in the embodiment of the present invention, wherein FIG. 2A is a longitudinal sectional view in a closed state, FIG. 2B is a longitudinal sectional view in an open state, and FIG. FIG. 2C is a sectional view taken along line CC of FIG.

FIG. 3 is a longitudinal sectional view of a cap for a liquid fuel tank of an engine used in the embodiment of the present invention.

4A is a sectional view taken along line IV-IV of FIG. 3, FIG.
(B) is a perspective view around the insertion opening of the fuel supply cylinder of the tank used in the embodiment of the present invention.

5A and 5B are views for explaining a cap for a liquid fuel tank of an engine according to the related art, where FIG. 5A is a longitudinal sectional view and FIG.
(B) is a longitudinal sectional view of the pressure relief valve.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pressure release valve, 2 ... Valve housing part, 3 ... Tank, 4 ... Pressure release hole, 5 ... Opening, 6 ... Valve seat, 7 ... Valve, 8 ... Inner bottom surface,
9: ring portion, 11: ridge, 12: fulcrum, 13: center axis, 14: both ends, 15: inner peripheral surface.

Claims (3)

[Claims] 1. A pressure release hole (4) communicating with the inside of a tank (3) is formed in an inner bottom of a valve body accommodating portion (2) of a pressure release valve (1), and an opening of the pressure release hole (4) is provided. (5) is provided with a valve seat (6), and this valve seat (6)
When the internal pressure of the tank (3) exceeds a predetermined value, the internal pressure of the tank (3) rises from the valve seat (6), and the internal pressure of the tank (3) is reduced by the pressure release hole. In the cap for a liquid fuel tank, which can be released to the atmosphere through (4), the opening of the pressure release hole (4) from the inner bottom surface (8) of the valve housing (2)
The ring (9) surrounding the ring (5) is raised, and the rising end face of the ring (9) is used as a valve seat (6). A ridge (11) is raised from the inner bottom surface (8) of the ridge, and the rising end face of the ridge (11) is used as a fulcrum (12).
A valve body (7) is placed on the valve seat (6) and the fulcrum (12), and the valve body (7) is pressed against the valve seat (6) and the fulcrum (12) by magnetic force. The valve body (7) is a valve seat with the part (12) as a fulcrum
(6) A cap for a liquid fuel tank, which is lifted from (6). 2. The cap for a liquid fuel tank according to claim 1, wherein the fulcrum portion (12) is formed in a direction parallel to a central axis (13) of the pressure release hole (4). Center axis of
(13) A cap for a liquid fuel tank, which is formed in an arc shape centered on (13). 3. The valve body receiving part (2) according to claim 2, wherein both ends (14) of the ridge (11) forming the fulcrum part (12) are extended. Inner peripheral surface (1
5) A liquid fuel tank cap connected to 5).