JP2002308314A - Sealing member and cap device for tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gasket GS to be used for a fuel cap 10, of which the deformation amount for an external force fa is small, and which has an excellent sealing property. SOLUTION: The fuel cap 10 is equipped with the gasket GS at the upper section of the outer periphery of a casing body 20. The gasket GS has an approximately oval-shape cross section having a longer diameter Ra and a shorter diameter Rb. Also, the gasket GS is equipped with a slit GSs having an approximately V-shape cross section with a depth Ls. In this case, Ra/Rb is 1.15 to 1.40, and Ls/Rb is 1.05 to 1.40. Then, the gasket GS is arranged in such a manner that the compressing direction may meet the direction of the longer diameter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal member interposed between a tank opening and a cap, and a tank cap device using the seal member.

[0002]

2. Description of the Related Art Conventionally, as a tank cap device of this kind, a fuel cap equipped with a C-shaped gasket (seal member) is rotated by two or three times with respect to a filler neck connected to the fuel tank. A configuration for opening and closing an inlet is known. Since the operation of the fuel cap a plurality of times may cause a state in which the fuel cap is not sufficiently tightened, as a technique for solving this, a predetermined angle, for example, 9
A configuration is known in which the injection port is closed by the fuel cap only by rotating about 0 ° (Japanese Patent Laid-Open No. 2000-344266).
No.). The fuel cap has two cap-side engaging portions formed on the outer periphery of the casing and formed at a circumferential interval of 180 °, and the two cap-side engaging portions are formed on the inner wall of the filler neck. The fuel cap is fixed to the filler neck by engaging with the opening side engaging portion.

[0003]

However, in the prior art, the fuel cap and the filler neck are engaged at two places at a cap-side engaging portion and an opening-side engaging portion at a circumferential interval of 180 °. When an external force is applied upwards due to an accident, etc., at a site away from the engagement point, the C-shaped gasket is greatly deformed, and the pressing force of the filler neck against the sealing surface decreases. However, there is a problem that the sealing performance is reduced. In addition, even with such a fuel cap that closes at a small operation angle, the operation feeling that the tightening operation can realize that the fuel cap is securely closed, that is, the operation feeling that is light at the start of operation and gradually becomes heavy Was required.

The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a sealing member having a small amount of deformation with respect to an external force and excellent sealing properties while improving characteristics of operation feeling at the time of tightening. To provide,
An object of the present invention is to provide a tank cap device using the same.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. According to the present invention, there is provided a seal member interposed between a seal surface of a tank opening and a cap, wherein the seal member has a long diameter. , A slit having a substantially V-shaped cross section having a depth of Ls and an opening width of Ws, having a substantially O-shaped cross section with Ra and a minor axis being Rb, and having a Ra / Rb of 1.1.
5 to 1.40, and Ls / Rb is 1.05 to 1.4.
0, Ws / Ra is 0.4 to 0.7, and the sealing member is arranged so that the compression direction thereof coincides with the direction of the major axis.

Another aspect of the present invention is a cap having a tank opening having an opening-side engaging portion, a cap having a cap-side engaging portion for closing the tank opening and engaging with the opening-side engaging portion, A seal member interposed between the sealing surface of the opening and the cap to seal the gap therebetween,
In the tank cap device, in which the cap is engaged with the opening-side engaging portion by rotating the cap at 180 ° or less, the seal member has a major axis of Ra and a minor axis of Rb. A circular, substantially V-shaped slit having a depth of Ls and an opening width of Ws is provided.
Rb is 1.15 to 1.40, and Ls / Rb is 1.0
5 to 1.40, Ws / Ra is 0.4 to 0.7, and the sealing member is arranged so that the compression direction of the sealing member coincides with the direction of the major axis.

In the seal member according to the present invention, when a compressive force is applied in the direction of the major axis, the slit having a V-shaped cross section is completely crushed, then elastically compressed, and is pressed against the seal surface to thereby open the tank opening. Seal between the sealing surface and the cap. Since the sealing member does not require a sudden compression force during the initial period until the slit is collapsed, it does not hinder the closing of the cap. Then, after the slit is crushed, a gradually larger compressive force is required. Therefore, at the time of the cap tightening operation, the operation becomes lighter and gradually heavier at the start of the operation, so that it is possible to obtain an operation feeling in which the user can feel that the cap is securely closed. After the slit is completely collapsed, the seal member is elastically compressed in the direction of the major axis. In this case, the sealing member
Because of the oval shape, a large seal holding load can be obtained with respect to an external force applied in the direction of the long diameter as compared with the C-shaped cross section described in the related art. Moreover, since the direction of the major axis of the seal member is arranged so as to coincide with the compression direction of the seal member, the seal surface does not become large.

Here, assuming that the major axis is Ra and the minor axis is Rb, the aspect ratio (Ra / Rb) of the sealing member is 1.15 to 15.5.
1.40. If the aspect ratio is less than 1.15, the amount of deformation due to rubber elasticity after the slit is closed is small, and the required amount of compression cannot be obtained.
If the ratio exceeds 1.40, that is, if the length is too long, the force in the tightening direction escapes in addition to the up and down directions, and the side portion of the sealing member partially deforms such as protruding, thereby impairing the sealing performance. Because it is The V-shape of the slit is represented by L, where Ss is the depth of the slit and Ws is the opening width.
s / Rb is 1.05 to 1.40, and Ws / Ra is 0.4 to 0.7. This is because if the slit is too small, it will collapse quickly and the reaction force will increase from the small amount of compression, and the operation feeling will deteriorate, while if the slit is too large, the amount of compression will be large until the slit is closed. This is because the operation rotation angle of the cap until the seal holding load equal to or more than the predetermined value is obtained becomes large.

Further, in the tank cap device according to another invention, when the cap is inserted into the tank opening and rotated at an angle of 180 ° or less in the closing direction, the cap-side engaging portion engages with the opening-side engaging portion. And a sealing member interposed between the cap and the sealing surface of the tank opening is pressed to seal the gap therebetween.

When the cap-side engaging portion projects from the outer periphery of the cap, a gap is formed between the outer peripheral surface of the cap and the inner wall of the tank opening at a position where there is no cap-side engaging portion. Even when the gap is large, the cap does not tilt significantly due to a large external force because the seal holding load of the seal member is large. Accordingly, the seal member is not excessively elastically deformed, and the sealing performance with respect to the seal surface is not reduced.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the configuration and operation of the present invention described above, a preferred embodiment of the present invention will be described below.

FIG. 1 is a half sectional view showing a fuel cap 10 (cap for a tank) according to an embodiment of the present invention. In FIG. 1, a fuel cap 10 has an inlet FNb (tank opening) for supplying fuel to a fuel tank (not shown).
The casing body 20 is attached to the filler neck FN having the following. The casing body 20 is formed of a synthetic resin material such as polyacetal, and the lid is mounted on the upper part of the casing body 20 and is formed of a synthetic resin material such as nylon. A body 40, a torque mechanism 80, and a gasket GS (seal member) mounted on the outer periphery of the upper portion of the casing main body 20 and sealing between the filler neck FN and the body 40 are provided.

Next, the configuration of each part of the fuel cap 10 according to the present embodiment will be described in detail. The casing main body 20 includes a substantially cylindrical outer tube 21 having a cap-side engaging portion 20a engaged with an inner peripheral portion of the filler neck FN, and a valve chamber forming body provided inside the outer tube 21. 2
2 is provided. The valve chamber forming body 22 includes a valve chamber 23 in which a positive pressure valve 60 and a negative pressure valve 70 are housed. The positive pressure valve 60 and the negative pressure valve 70 are pressure regulating valves for maintaining the pressure within a predetermined range in the fuel tank, but the details thereof are well known and will not be described.

A gasket GS is provided on the lower surface of the upper flange 33 of the casing body 20. The gasket GS is interposed between the seal holding portion 21a of the flange 33 and the inlet FNb of the filler neck FN. When the fuel cap 10 is tightened into the inlet FNb, the gasket GS is pressed against the seal holding portion 21a. Acts as a seal. Further, a cap-side engaging portion 20a is formed at a lower portion of the outer periphery of the outer tube 21. FIG. 2 is an explanatory diagram illustrating the relationship between the cap-side engaging portion 20a of the casing body 20 and the filler neck FN. As shown in FIG. 2, an opening-side engaging portion FNc is formed on the inner peripheral portion of the filler neck FN. A neck-side insertion notch FNd into which the cap-side engaging portion 20a of the fuel cap 10 can be inserted in the axial direction is formed at a part of the inner peripheral side of the opening-side engaging portion FNc.

FIG. 3 shows a cap-side engaging portion 20a and an opening-side engaging portion FN protruding from the outer peripheral surface of the casing body 20.
FIG. 4 is an explanatory diagram for explaining a relationship with c. Opening side engaging part FN
c is formed to be inclined by a first angle α1 with respect to a direction perpendicular to the direction in which the fuel cap 10 advances and retreats (axial direction). On the other hand, the cap side engaging portion 20a is
b. The guide surface 20b includes a first inclined portion 20c formed at a second angle α2 larger than the first angle α1,
A second inclined portion 20d formed continuously with the first inclined portion 20c and inclined at the same angle as the first angle α1.

When the fuel cap 10 is rotated by a predetermined angle (about 90 °) in a state where the cap side engaging portion 20a is aligned with the neck side notch FNd and the fuel cap 10 is inserted into the filler neck FN, Cap side engaging part 2
0a moves along the arrow D1, and the opening side engaging portion FNc
, The fuel cap 10 is mounted on the filler neck FN. The guide surface 20b
However, the reason for having the first inclined portion 20c and the second inclined portion 20d will be described together with the opening / closing operation of the fuel cap 10 described later.

FIG. 4 is an exploded perspective view showing the periphery of a torque mechanism 80 mounted on the lid 40 and the upper part of the casing body 20, and FIG. 5 is a view of the vicinity of the torque mechanism 80 along the line VV in FIG. FIG. The torque mechanism 80 gives a sense of moderation when the lid 40 receives a rotation torque of a predetermined value or more during the operation of closing the inlet FNb with the fuel cap 10,
This is a mechanism for confirming that the fuel cap 10 is attached to the filler neck FN with a predetermined rotation torque.

The upper flange 33 of the casing body 20
Has a lid 40 rotatably and detachably attached thereto. The lid 40 includes an upper wall 41, a handle 42 protruding from an outer wall of the upper wall 41, and a side wall 43 formed on an outer peripheral portion of the upper wall 41, and is integrally formed by injection using a conductive resin. Is molded. Eight engagement projections 45 are provided at equal intervals along the circumferential direction inside the side wall 43.
The lid 40 is assembled to the casing body 20 by the engagement protrusion 45 engaging the flange 33.

As shown in FIGS. 4 and 5, the torque mechanism 80 includes main body side ribs 32, which are provided upright on the outer periphery of the outer tube 21 of the casing main body 20, and a cylindrical shaft portion of the lid 40. 46, lid side engaging portions 46a, 46a, lid side trigger projections 47, 47, spring 82, torque plate 9
0. That is, a cylindrical shaft portion 46 is protrudingly provided at the center of the inside of the lid 40, and this cylindrical shaft portion 46 is provided.
Are formed on the outer peripheral portion with a lid-side engaging portion 46a. Further, on the outer peripheral portion of the inner surface of the lid 40, lid-side trigger projections 47, 47 are provided to protrude in an arc shape.
Lid-side engaging portions 46a, 46a and lid-side trigger projection 4
7 and 47 are formed symmetrically about the rotation axis of the lid 40.

The spring 82 is a coil spring interposed between the casing main body 20 and the torque plate 90. The spring 82 is provided between the upper part of the casing main body 20 and the outer peripheral portion of the torque plate 90, so that the torque is increased. When the plate 90 is rotated counterclockwise with respect to the casing body 20, the urging force is accumulated.

As shown in FIG. 5, the torque plate 90
Is a thin disk formed of resin and has a through hole and a guide groove. That is, a center hole 91 is formed in the center of the torque plate 90, and rib guides 93, 93 are formed concentrically therewith, and trigger guide grooves 95, 95 are formed on the outer peripheral side thereof. In the central hole 91,
The cylindrical shaft portion 46 of the lid 40 penetrates, and elastic torque pieces 94, 94 are formed on the peripheral edge thereof. The elastic torque pieces 94, 94 are formed in an arched cantilever with the support end 94a as a fulcrum, and a plate-side engaging portion 94b is protruded from the inner peripheral side to form the plate-side engaging portion 94b.
An elongate hole 94c is formed on the outer peripheral side. The elastic torque pieces 94, 94 are formed so that when the plate-side engaging portion 94b is pressed by the lid-side engaging portion 46a of the lid 40, the elongated torque portion 94b is elastically deformed so as to narrow the elongated hole 94c (FIG. 7
reference).

The body-side ribs 32, 32 are inserted into rib guide portions 93, 93 arranged on the outer peripheral side of the elastic torque pieces 94, 94, respectively. Body side rib 32
Reciprocates between a pressing end 93a and a pressing end 93b, which are both ends of the rib guide portion 93. The lid-side trigger projections 47 are inserted into the trigger guide grooves 95. The lid-side trigger projection 47 is a pressing end 95 of the trigger guide groove 95 which is both ends of the trigger guide groove 95.
reciprocate between the a and the pressing end 95b.

Next, the inlet FNb of the filler neck FN
The operation of the torque mechanism 80 when the operation of opening and closing with the fuel cap 10 is performed will be described. Since two torque mechanisms 80 are provided around the rotation axis of the lid 40, the description will be made focusing on the upper side in the figure.

As shown in FIG. 2, with the inlet FNb open, the handle 42 of the lid 40 is sandwiched between the thumb and the index finger, and the cap-side engaging portion 20a of the casing body 20 is opened.
Is aligned with the neck side notch FNd of the filler neck FN and inserted in the axial direction. At this time, when the handle 42 of the lid 40 is oriented substantially vertically, the cap-side engaging portion 20a and the neck-side insertion notch FNd are arranged at positions where the cap-side engaging portion 20a and the neck-side insertion notch FNd can be inserted. In a relationship. At this time, as shown in FIG. 6, the positional relationship of the torque mechanism 80 is such that the main body side rib 32 is pressed against the pressing end 93a by the urging force of the spring 82, and the lid side engaging portion 46a of the lid 40 is It is in a state of contacting the plate-side engaging portion 94b of the torque plate 90.

In this state, when a closing operation is performed by applying a clockwise turning force to the lid 40, the torque mechanism 8 is closed.
0 performs a series of operations as shown in FIG. 9 through FIG. 7 from the state of FIG. That is, the clockwise turning force applied to the lid 40 is transmitted to the torque plate 90 via the engagement between the lid-side engaging portion 46a of the lid 40 and the plate-side engaging portion 94b of the torque plate 90. Then, the torque plate 90 is rotated in the same direction. This torque plate 9
0, the main body side rib 32 of the casing main body 20 is rotated.
Is pressed by the pressing end 93 a of the torque plate 90. As a result, the lid 40, the torque plate 90, and the casing main body 20 rotate integrally, advance in a direction to close the inlet FNb, and the force with which the cap-side engaging portion 20a engages with the opening-side engaging portion FNc increases. I do. When the reaction force generated by the engaging force is equal to or more than a predetermined rotational torque, as shown in FIG.
Overcoming b, the first disengagement state shown in FIG. 8 is obtained. This first
After going through the disengagement state, the user can confirm the sense of moderation. Thereby, the fuel cap 10 is connected to the injection port FNb.
At a predetermined tightening torque.

On the other hand, to open the fuel cap 10, the handle 42 of the lid 40 is gripped with a finger, and as shown in FIG.
Apply a force that rotates counterclockwise. Thereby, the lid 4
The lid-side engaging portion 46a of the zero presses the plate-side engaging portion 94b of the torque plate 90. At this time, since the casing body 20 is restrained by engagement with the filler neck FN, only the lid 40 and the torque plate 90 rotate counterclockwise against the urging force of the spring 82. Therefore, with this rotation, the main body side rib 32 relatively moves inside the rib guide portion 93 toward the pressing end 93b.

In the state shown in FIG. 9, if the rib 32 on the main body side is not located at the end of the elastic torque piece 94, the elastic torque piece 94 is easily bent. When the lid 40 is further rotated in the counterclockwise direction from this state, as shown in FIG. 10, the lid-side engaging portion 46a presses the plate-side engaging portion 94b and the portion 94d abutting on the main-body-side rib 32. At the center, and elastically deform so as to change the width of the elongated hole 94c.
The second disengagement state of overcoming 4b is reached (the state of FIG. 11). That is, the lid-side engaging portion 46a gets over the plate-side engaging portion 94b with a smaller rotational torque than when the fuel cap 10 is closed.

When the lid 40 rotates counterclockwise to a position where the lid-side engaging portion 46a has climbed over the plate-side engaging portion 94b, the lid-side trigger projection 47 hits the pressing end 95a of the torque plate 90. In this state, since the main body side rib 32 is also in contact with the pressing end 93b of the rib guide portion 93, the rotational force applied to the lid 40 is limited to the lid side trigger projection 47, the torque plate 90, the pressing end 93b, the main body side rib 32, The power is transmitted through the casing main body 20, and the lid body 40, the torque plate 90, and the casing main body 20 integrally rotate counterclockwise.

When the casing main body 20 rotates about 90 ° integrally with the lid 40 (the state shown in FIG. 12), the cap-side engaging portion 20a becomes the opening-side engaging portion F of the filler neck FN.
Deviating from Nc, the casing body 20 is released from the binding force on the filler neck FN. At this time, the casing main body 20 receives the urging force of the spring 82 between the casing main body 20 and the torque plate 90, while the lid body 40 is held and held by the finger.
It rotates counterclockwise with respect to the lid 40 and the torque plate 90, and returns to the original position (the state of FIG. 13). That is, the positional relationship between the handle 42 of the lid 40 and the cap-side engaging portion 20a of the casing body 20 returns to the initial state.

As described above, during the operation of closing the fuel cap 10, when the lid-side engaging portion 46a of the lid 40 gets over the plate-side engaging portion 94b of the torque plate 90, a sense of moderation can be confirmed. Since it can be seen that 10 is tightened with a predetermined torque, it can be tightened with a constant torque regardless of the elasticity of the gasket GS or the like.

In addition, the fuel cap 10 can be operated at a small rotation angle of about 90 ° by the engagement between the cap-side engaging portion 20a and the opening-side engaging portion FNc. And the mounting work is easy.

According to the torque mechanism 80, when a rotational torque is applied to the lid 40 in a counterclockwise direction to open the fuel cap 10, the plate-side engaging portion 94b and the lid-side engaging portion 46a Means that the spring 8 is disengaged in the second disengagement state having a smaller rotational torque than the first disengagement state.
2 does not hinder the accumulation of the urging force, and the accumulated urging force can return the positional relationship between the lid 40 and the casing body 20 to the initial state.

Therefore, when the fuel cap 10 is always closed, the handle 42 of the lid 40 and the casing body 20 are closed.
Alignment with the cap-side engaging portion 20a is facilitated, and the work of closing the inlet FNb of the filler neck FN is simplified.

Next, when the fuel cap 10 is closed, the cap-side engaging portion 20a is connected to the opening-side engaging portion F with reference to FIG.
The operation for engaging with Nc will be described. FIG. 14 is an explanatory diagram illustrating a series of operations in which the cap-side engaging portion 20a engages with the opening-side engaging portion FNc. When the fuel cap 10 is inserted into the filler neck FN, the cap-side engaging portion 2
0a is inserted into the neck side insertion notch FNd, that is, inserted into the back as shown in FIG. 14B via FIG. 14A.

Subsequently, when the fuel cap 10 is rotated clockwise, as shown in FIG.
c follows the opening side engaging portion FNc (first engaging process). Further, as shown in FIG. 14D, when the fuel cap 10 is rotated clockwise, the second inclined portion 20d moves following the opening side engaging portion FNc (second engaging process), and the fuel cap 10 is rotated. Closes the inlet FNb of the filler neck FN.

Here, as shown in FIGS. 14C and 14D, the moving distance of the cap-side engaging portion 20a in the rotating direction is x, and the moving distance of the cap-side engaging portion 20a in the axial direction is y. If the rate TR is defined as y / x, and the moving distance in the rotational direction in the first engagement process and the second engaging process is x1, x2 and the moving distance in the axial direction is y1, y2, the interference margin change rate is T
R1 and TR2. At this time, since the second angle α2 of the first inclined portion 20c is larger than the first angle α1 of the second inclined portion 20d, the interference change rate TR1 in the first engagement process is equal to the second angle α2.
It is larger than the interference change rate TR2 in the engagement process. The reason why the interference change rate TR1 is set large in the initial first engagement process and the interference change rate TR2 is reduced in the second engagement process is as follows.

FIG. 15 is a graph illustrating the relationship between the amount of compression (an interference) when the gasket is crushed and the reaction force of the gasket. In FIG. 15, the reaction force of the gasket gradually increases at the initial compression amount, but rises sharply as the compression amount increases. That is, the gasket requires a small force to obtain a large amount of compression in an early stage, but requires a large force to compress in a stage where the gasket is compressed to some extent.

By utilizing the properties of the gasket shown in FIG. 15, in the closing operation of the fuel cap 10, even if the gasket GS is compressed at a large interference change rate TR1 in the first engagement process with a small reaction force, The reaction force of the gasket GS is also small, and the gasket GS does not slip. Then, in the second engagement process in which the reaction force is large following the first engagement process, the reaction force of the gasket GS gradually increases. However, since the gasket GS is gradually compressed with a small interference change rate TR2, There is no slipping by the torque mechanism 80.

In the second engagement process, the cap-side engagement portion 20a moves by a long movement distance along the opening-side engagement portion FNc on the second inclined portion 20d.
An engagement state with sufficient play in the rotation direction is achieved at Nc, and the fuel cap 10 can be prevented from coming off the filler neck FN.

Therefore, in the initial stage of compressing the gasket GS (first engagement process), the first inclination with a large inclination angle is performed.
By fitting the inclined portion 20c to the opening side engaging portion FNc, even with a short rotation operation angle, a sufficient interference can be taken with respect to the gasket GS without receiving a large reaction force, and thus the height is high. Sealing property can be obtained.

When the fuel cap 10 is closed, the cap side engaging portion 20a is moved from FIG. 14B to FIG.
Move from the right side to the left side as shown in FIG. In this case, the second angle α2 of the cap-side engaging portion 20a is
Since the opening side engaging portion FNc is larger than the first angle α1, the corner 20e of the cap side engaging portion 20a does not strike the opening side engaging portion FNc when hitting the opening side engaging portion FNc. Then, as shown in FIG. 14 (D), the second inclined portion 20d follows the opening side engaging portion FNc almost uniformly in surface contact with a small torque. Therefore, the fuel cap 10 has the first inclined portion 20c and the opening-side engaging portion FN.
The motor rotates smoothly without generating a large rotation torque between the motor and the motor. Therefore, when the fuel cap 10 is closed with the same rotation torque as compared with the conventional technology, the fuel cap 10 is closed at a large rotation angle, that is, the interference can be increased.

Even if the cap-side engaging portion 20a has a fine structure like the first inclined portion 20c and the second inclined portion 20d, it can be easily and accurately formed by injection molding integrally with the casing body 20. Can be. Therefore, such an inclined surface can be formed more easily than the case where it is processed and formed into the metal filler neck FN.

As described above, the first and second angles α1 and α2 of the inclined guide surface 20b are set to optimal values as appropriate depending on the shape of the fuel cap and the type of gasket. Operation angle 60 to 120
゜, when the interference of the gasket GS is set to 1.0 to 2.0 mm, the first angle α1 is preferably set to 3 to 8 °, and the second angle α2 is preferably set to 10 to 45 °. In particular, it is preferable to set α1 to 3 to 6 ° and α2 to 10 to 30 °.

Next, the configuration of the gasket GS will be described. FIG. 16 is a sectional view of the gasket GS. FIG.
, The gasket GS has an oblong shape with a long diameter Ra and a short diameter Rb, and the slit GSs is formed in a V-shaped groove. As shown in FIG. 17, when the fuel cap 10 is mounted on the filler neck FN, the gasket GS receives a compressive force. The gasket GS seals against the sealing surface FNf of the filler neck FN by being compressed and deformed by rubber elasticity after the slit GSs is crushed. In addition, the gasket GS has an elliptical shape and has a characteristic configuration of a slit GSs of a V-shaped groove, so that the seal holding load when receiving an external force is increased to prevent fuel leakage. . Here, when the seal holding load receives an external force from below on the lid 40 or the like,
It refers to the load when maintaining the sealing performance.

Next, the seal holding load of the gasket GS will be described. FIG. 18 is an explanatory diagram illustrating an operation when the fuel cap 10 receives the external force shown in FIG.
The fuel cap 10 is viewed from above.

The fuel cap 10 may receive an upward external force fa shown in FIG. 18 on the lid 40 or the like due to an accident or the like. In this case, since the external force fa is close to the engagement position Pa between the cap side engagement portion 24 and the opening side engagement portion FNc, the moment about the cap side engagement portion 24 as a fulcrum is small, and the fuel The cap 10 does not tilt greatly. On the other hand, when an upward external force fb shown in FIG.
The external force fb is applied to the cap-side engaging portion 24 and the opening-side engaging portion FNc.
, The moment about the cap side engaging portion 24 as a fulcrum is large, and the fuel cap 10 receives a large force for tilting. But,
Since the seal holding load of the gasket GS is large, the fuel cap 10 is not tilted significantly. Therefore, gasket G
S maintains the state of being in close contact with the sealing surface FNf, and does not impair the sealing performance.

The casing body 20 is formed in a cylindrical shape,
In the case where the cap-side engaging portion 24 is configured to protrude, a gap is formed between the outer peripheral surface of the casing body 20 and the inner wall of the filler neck FN at a position where the cap-side engaging portion 24 is not provided. By increasing the seal holding load of the gasket GS, rattling of the fuel cap 10 due to external force is prevented.

Next, the seal holding load of the gasket GS will be described together with the closing operation of the fuel cap 10. FIG.
Is a graph showing the relationship between the tightening torque applied to the fuel cap 10 and the rotation angle. The tightening torque and rotation angle in FIG. 19 correspond to the gasket GS in FIG.
Corresponding to the reaction force and the compression amount (the interference). This is because the amount of compression of the gasket GS is proportional to the amount of increase in the rotation angle of the fuel cap 10, and the tightening torque is proportional to the reaction force from the gasket GS.

In FIG. 19, the solid line indicates this embodiment, and the dashed line indicates the comparative example (conventional example). Here, the embodiment is shown in FIG.
As shown in FIG. 6, the slit GSs is V-shaped and the hardness is 60.
In the conventional example, as shown in FIG.
It is shaped like a letter and has a hardness of 70. Now, as the handle 42 is rotated to close the fuel cap 10, the gasket GS is compressed by receiving an axial force, and the tightening torque of the fuel cap 10 increases.

In the embodiment, the turning angle becomes a bending point at the predetermined angle θα, and the tightening torque increases rapidly. This is because the gasket GS mainly has the slit G
Ss is a process of collapsing, and the compressive force acts to narrow the gap between the slits GSs. In other words, the tightening torque is a small force that elastically deforms the connecting portion of the gasket GS other than the slit GSs, and this value continues up to the bending point where the gap is eliminated. When the gasket GS completely closes the slit GSs after the inflection point, ie, when the gasket GS completely closes the slit GSs, the whole is compressed by rubber elasticity, so that the tightening torque sharply increases.

As described above, when the fuel cap 10 is closed, the tightening torque gradually increases to the bending point, so that the initial reaction force is small, and there is no hindrance to the closing operation as described with reference to FIG. . And gasket GS
Is suitable for the torque mechanism 80 (see FIG. 4 and the like) which is required to have a small operation angle until closing because the rotation angle θf1 from when the slit GSs is closed to when the predetermined tightening torque Ta is reached is also small. Applicable to In addition, when the fuel cap 10 is closed, the reaction force is small in the early stage when the slit GSs is crushed, so it is light at the start of the operation and gradually becomes heavy after being crushed, so that it is possible to obtain an operation feeling that can realize that it is securely closed. it can. Moreover, even when the gasket GS is tightened at a small rotation angle, the gasket GS is sealed in a state where the tightening torque Ta is large, that is, in a state where the reaction force is large, so that even when an external force is applied to the lid or the like. A large seal holding load can be obtained.

On the other hand, in the comparative example, the predetermined angle θα
, The slit does not completely collapse, leaving a gap in the center, and a large rotation angle θf2 is required to completely collapse the slit. For this reason, the initial reaction force is small as in the embodiment, but a large rotation angle is required until the predetermined tightening torque Ta is reached.
It cannot sufficiently cope with the case where it is necessary to close at a small angle such as 0. Also, at the stage of the rotation angle θf1 in the comparative example, the slit of the C-shaped groove has a gap at the center even if the opening is closed and is not completely collapsed, so that the closed rotation angle is set to θf1. Does not have a large seal holding load.

The characteristics of the gasket GS described above can be suitably realized under the following conditions.

(1) Regarding the outer shape of the gasket GS, as shown in FIG.
a, and the minor axis is Rb, the aspect ratio Kab (= Ra / R
b) preferably ranges from 1.15 to 1.40. This is because when the aspect ratio is less than 1.15, the amount of deformation due to rubber elasticity after the slit is closed is small,
If the required amount of compression cannot be obtained, while if it exceeds 1.40, that is, if it becomes too long, the force in the tightening direction escapes to other than up and down, and the side portion of the sealing member partially This is because deformation such as sticking out occurs and sealability is impaired.

(2) Regarding the shape of the slit GSs, if the opening width is Ws, Ws / Ra is 0.4 to 0.4.
0.7. This is because if the slit GSs is too small, it is immediately collapsed, the reaction force increases from a small amount of compression, and the operation rotation angle of the lid 40 decreases, while if the slit GSs is too large, This is because the rotation angle until the slit GSs is closed increases, and the operation rotation angle of the lid 40 until a seal holding load equal to or more than a predetermined value is obtained increases.

(3) As for the depth Ls of the slit GSs, the ratio Ks (Ls / Rb) of the depth Ls of the slit GSs to the minor diameter Rb is preferably 1.05 to 1.40. If the slit GSs is less than 1.05, the above-described effects cannot be obtained, and the slit GSs
When the depth is large, in addition to the above-described effects, excellent absorbency against variations in vertical tightening dimensions is obtained. However, when the depth exceeds 1.40, the vertical rubber reaction force is reduced, and the sealing performance is reduced. is there. Specifically, when the major axis Ra is 3.5 mm and the minor axis Rb is 2.9 mm, the slit GSs has a slit opening width Ws of 1 to 2 mm and a depth Ls of the slit of 2.9 to 2.9 mm. It is preferably 3.9 mm.

(4) The hardness of the rubber of the gasket GS is
It is preferably 60 to 65 in HS of Japanese Industrial Standards (JIS). This is because, if it is too hard, the initial reaction force becomes large, while if it is too soft, a sufficient seal holding load cannot be obtained.

The present invention is not limited to the above-described embodiment, but can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

(1) In the above embodiment, the seal member (gasket) is attached to the fuel cap. However, the seal member (gasket) is not particularly limited as long as the seal member (gasket) moves to the direction in which the fuel cap closes to seal the gap between the filler neck. Instead, for example, it may be provided on the filler neck side.

(2) The fuel cap is configured to apply a torsional force to the gasket by rotating the fuel cap. However, the fuel cap may be configured to be closed by an operating force in the vertical direction if a force is applied in the compression direction.

(3) The tank device using the sealing member is not limited to the fuel tank, but may be a tank device for storing other liquid.

[Brief description of the drawings]

FIG. 1 shows a fuel cap 1 according to an embodiment of the present invention.
FIG.

FIG. 2 is a cap-side engaging portion 20a of a casing body 20;
FIG. 5 is an explanatory diagram for explaining a relationship between the filler neck and the filler neck.

FIG. 3 is a cap-side engaging portion 20a of the casing body 20;
FIG. 7 is an explanatory diagram for explaining an operation of engaging with an opening-side engaging portion FNc.

FIG. 4 is an exploded perspective view showing the periphery of a torque mechanism 80 mounted on the lid 40 and the upper part of the casing body 20.

FIG. 5 is a sectional view showing the vicinity of a torque mechanism 80 along the line VV in FIG. 1;

FIG. 6 is an explanatory diagram for explaining the operation of the torque mechanism 80.

FIG. 7 is an explanatory diagram illustrating an operation subsequent to FIG. 6;

FIG. 8 is an explanatory diagram illustrating an operation following FIG. 7;

FIG. 9 is an explanatory diagram illustrating an operation following FIG. 8;

FIG. 10 is an explanatory diagram illustrating an operation following FIG. 9;

FIG. 11 is an explanatory diagram illustrating an operation following FIG. 10;

FIG. 12 is an explanatory diagram illustrating an operation following FIG. 11;

FIG. 13 is an explanatory diagram illustrating an operation subsequent to FIG. 12;

FIG. 14 is a sectional view showing a state in which the cap-side engaging portion 20a is an opening-side engaging portion
It is explanatory drawing explaining a series of operation | movement which engages with c.

FIG. 15 is a graph illustrating a relationship between a compression amount (an interference) when a gasket is crushed and a reaction force of the gasket.

FIG. 16 is a sectional view of a gasket GS.

FIG. 17 is a sectional view showing a main part of a fuel cap.

18 is an explanatory diagram illustrating an operation when the fuel cap 10 receives the external force shown in FIG.

FIG. 19 is a graph showing the relationship between the tightening torque applied to the fuel cap 10 and the rotation angle.

FIG. 20 is an explanatory view illustrating the shape of a conventional gasket.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Fuel cap 20 ... Casing main body 20a ... Cap side engaging part 20b ... Guide surface 20c ... First inclined part 20d ... Second inclined part 20e ... Corner 20Ba ... Casing side engaging part 20Bc ... Inclined surface 21 ... Outer tube body 21a ... seal holding part 22 ... valve chamber forming body 23 ... valve chamber 32 ... body side rib 33 ... flange part 40 ... lid 41 ... bottom wall 42 ... gripping part 43 ... side wall 45 ... engagement protrusion 46a ... lid body side engagement Joint part 46 ... Cylindrical shaft part 47 ... Lid side trigger projection 60 ... Positive pressure valve 70 ... Negative pressure valve 80 ... Torque mechanism 82 ... Spring 90 ... Torque plate 91 ... Center hole 93b ... Pressing end 93a ... Pressing end 93 ... Rib guide Part 94 ... Elastic torque piece 94a ... Support end part 94b ... Plate side engaging part 94c ... Elongated hole 94d ... Part 95 ... Trigger guide groove 95a ... Pressing end 95b ... Press End 100 ... fuel cap GS ... Gasket FN ... filler neck FNb ... inlet FNc ... opening engagement FNd ... neck side inserting notch

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D038 CA22 CA32 CC15 3E084 AB04 BA03 CA01 CB04 CC03 DA01 DC03 EA04 EB03 EC03 FA09 GA03 GB03 GB17 HA05 HB04 HC03 HD04 KA05 3J040 AA01 AA11 BA03 EA01 FA05

Claims (2)

[Claims] 1. A sealing member interposed between a sealing surface of a tank opening and a cap, wherein the sealing member is substantially oval in cross section having a major axis of Ra and a minor axis of Rb, a depth of Ls, and an opening width. , The slit having a substantially V-shaped cross section with Ws as Ra, Rb / Rb is 1.15 to 1.40, Ls / Rb is 1.05 to 1.40, and Ws / Ra is 0.4 to 0.7. The seal member is arranged so that the compression direction of the seal member coincides with the direction of the major axis. 2. A tank opening having an opening-side engaging portion, a cap having a cap-side engaging portion for closing the tank opening and engaging with the opening-side engaging portion, and a sealing surface of the tank opening. A sealing member interposed between the cap and the cap to seal the gap therebetween; and a cap device for rotating the cap at 180 ° or less to engage the cap-side engaging portion with the opening-side engaging portion. In the above, the sealing member has a substantially V-shaped slit having a major axis of Ra, a minor axis of Rb, and a substantially oval cross section, a depth of Ls, and an opening width of Ws, and a Ra / Rb of 1.15. Ls / Rb is 1.05 to 1.40, Ws / Ra is 0.4 to 0.7, and the seal member is arranged so that the compression direction of the seal member coincides with the direction of the major axis. That is characterized by Click cap device.