JP2579849Y2 - Check valve - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a check valve for preventing a back flow in a fuel supply system of a fuel tank of an automobile, for example.

[0002]

2. Description of the Related Art Conventionally, as a backflow prevention valve for preventing backflow in a fuel supply system of a fuel tank of an automobile, for example, the one described in Japanese Utility Model Laid-Open No. 63-132178 is known. This includes a cylindrical case that is inserted into and attached to a flow path of the fuel supply system (for example, a fuel hose connection port of a fuel tank), and a case provided in the case to prevent backflow into the flow path. Consisting of a closing valve
On the outer periphery of the case, there is formed a flexible piece which is locked in the flow path at the time of insertion so as to keep the case attached to the flow path end.

That is, the case is provided with a notch indicated by reference numeral 5 in the above-mentioned publication, whereby four flexible pieces are formed in this case, and a projection (reference numeral 4) provided on the flexible piece is a tube. It is configured to bite into the inner wall of the road (reference numeral 12) and lock it.

[0004]

The check valve described above is easily mounted simply by inserting it into the flow path of the fuel supply system, for example, to prevent a problem that fuel is blown out by internal pressure when the fuel supply port is opened. However, it has the following problems to be improved.

That is, since the case is provided with a notch in order to form a flexible piece for locking, no matter how much the valve body blocks the inside of the case, there is no gap between the outer periphery of the case and the inner surface of the oil supply hose connection port. The fuel tank and the fuel supply hose communicate with each other via the gap and the notch, and a slight backflow may occur from this, and the sealing performance may be reduced.

The present invention has been made in view of such problems of the prior art, and has as its object to provide a non-return valve capable of preventing a reverse flow without leaking while ensuring easy installation in a flow path. The purpose is.

[0007]

The gist of the present invention for achieving the above-mentioned object lies in the following items. [1] A cylindrical case (1) which is inserted into and attached to a flow path (30), and is provided in the case (1) so as to be swingable, and one direction of a fluid in the flow path (30). A check valve comprising a valve element (10) for opening and closing the case (1) so as to allow a flow to the case and to prevent a reverse flow in a direction opposite to the one direction. The whole is formed in a cylindrical shape conforming to the shape of the flow path (30), and a part of the peripheral wall is bent so as to protrude inwardly of the cylinder, so that the bent part of the peripheral wall and the flow path (30) are formed. 30) A space (6) that is airtight with respect to the flow path (30) is formed between the case (1) and the inner wall, and the case (1) is connected to the flow path (30).
The flexible piece (5) locked inside is integrated with the case (1),
A check valve which is displaceable from the outer peripheral surface side of the case (1) so as to enter the space (6). [2] A cylindrical case (1) which is inserted into and attached to the flow path (30), and is provided in the case (1) so as to be swingable, and one direction of the fluid in the flow path (30). A check valve comprising a valve element (10) for opening and closing the case (1) so as to allow a flow to the case and to prevent a reverse flow in a direction opposite to the one direction. The whole is formed in a cylindrical shape conforming to the shape of the flow path (30), and a part of the peripheral wall is bent to project inwardly of the cylinder, so that the bent part of the peripheral wall and the flow path (30) are formed. 30) A space (6) that is airtight with respect to the flow path (30) is formed between the case (1) and the inner wall, and the case (1) is connected to the flow path (30).
The flexible piece (5) locked inside is integrated with the case (1),
In addition, the flexible piece (5) is provided so as to be displaceable so as to enter the space (6) from the outer peripheral surface side of the case (1), and the flexible piece (5) is connected to the case (1) on the upstream side in the fluid flowing direction. , The downstream side and both sides are separated from the case (1) via a gap, and the bent portion of the peripheral wall of the case (1) moves from the upstream side to the downstream side in the fluid flowing direction. A check valve which is provided to be inclined so as to gradually project inward of the cylinder.

[0008]

The check valve of the present invention can be easily mounted because the flexible piece (5) is locked in the flow path (3) only by inserting the case (1) into the flow path (3). . Moreover, since the flexible piece (5) is provided in the space (6) which is made airtight with respect to the flow path (30) by bending the peripheral wall of the case (1),
Backflow flowing into the case (1) from the gap between the inner circumference of the flow path (3) and the outer circumference of the case cannot occur. In addition, the backflow that is going to pass directly through the case (1) is prevented by the valve body (10), so that the backflow into the flow path (3) is completely prevented.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIGS. 1 and 6, the check valve according to the present embodiment includes a case 1 that is inserted into and attached to an end of a pipe (flow path) 30 that is to prevent backflow, and a case 1 that is provided outside the case 1. A valve body 10 slidably provided in the opening to allow the fluid in the conduit 30 to flow in one direction and to open and close so as to prevent a backflow in a direction opposite to the one direction; A spring 20 biases the valve body 10 toward the closing side.

The case 1 has a cylindrical shape as a whole in which the outer periphery of the outer opening is expanded in a flange shape, and a hook-shaped shaft support 2 is formed at one end of the outer opening. An annular step 4 into which the valve body 10 at the closed position is fitted is formed on the inner surface of the opening. Then, the inner peripheral surface of the edge of the outer opening (in this case, coincides with the inner peripheral surface of the step portion 4).
Is a conical inclined surface 3 whose diameter decreases toward the inside of the case 1 so as to guide the valve element 10 when it swings inward.

As shown in FIGS. 1 and 5, case 1
A part of the peripheral wall is bent and protrudes inward of the cylinder, and a conduit 30 is provided between the bent part of the peripheral wall and the inner wall of the conduit 30.
A space 6 is formed which is airtight with respect to. In this space 6, a flexible piece 5 having a projection 5a on the outer surface is integrally provided. In a natural state, the flexible piece 5 is displaceable along the same cylindrical surface as the outer peripheral portion other than the space 6 of the case 1 (the outer peripheral surface side of the case 1) so as to enter the space 6 from the cylindrical surface. Is provided. As shown in FIG. 4, the flexible piece 5 is integrally connected to the case 1 on the upstream side in the direction in which the fluid flows, while being separated from the case 1 on the downstream side and both sides via a gap. . Further, as shown in FIG. 1, the part where the peripheral wall of the case 1 is bent is from the upstream side to the downstream side in the fluid flowing direction.
It is provided to be inclined so as to gradually project inward of the cylinder.
Further, on the outer periphery of the case 1, on the tip side of the space 6, there is formed an annular sealing projection 1 a that elastically adheres to the inner wall of the conduit 30.

As shown in FIG. 2, the valve body 10 has two arms 15 and 16 extending at one end of a disk-shaped main body, and linearly extending between these arms and on both sides thereof. The extended shaft portion 11 is formed. The valve body 10 is rotatably supported by the case 1 by a central portion of the shaft portion 11 being removably fitted into the shaft support portion 2. The outer peripheral surface 13 of the valve element 10 is a conical inclined surface that slides on the inclined surface 3 of the case 1 when the valve element 10 swings inward.
Is set slightly smaller than the inclined surface 3 of the case 1 so that the inner surface 13 of the valve body 10 is in close contact with the bottom surface of the step portion 4 of the case 1 as described above.

The spring 20 is formed by bending a linear material having elasticity such as a metal, and as shown in FIG.
A U-shaped portion 23 is formed between the two coil portions 21 and 22. The spring 20 has coil portions 21 and 22 fitted on both sides of the shaft portion 11, respectively.
Resiliently abuts a spring receiver 14 formed on the outer surface of the valve body 10, and both ends 24 and 25 respectively resiliently engage with recesses 7 and 8 (shown in FIG. 4) on both sides of the shaft support 2 in the case 1. Is mounted in a state of contact with the valve body 10.
Is in a state where a restoring force for urging is generated. The case 1 and the valve body 10 are made of, for example, a molded product of a synthetic resin.

Next, the operation will be described. The check valve is
As shown in FIG. 6, if a hole 31 (or a concave portion) with which the projection 5 a is engaged is formed at the end of the pipe line 30 where the backflow is to be prevented, it is easy to insert the end into the end. Can be mounted on

When no forward force is applied to the valve element 10 by a fluid such as fuel, as shown in FIG.
0 is forcibly at the closed position by the urging force of the spring 20, but when fuel or the like is fed into the conduit 30 and flows into this end of the conduit 30, the rotation center (shaft portion) of the valve body 10 1
Since 1) is located at the end, a large moment is generated in the valve body 10 by the force applied by the flowing fluid,
The valve element 10 opens instantaneously and opens greatly as shown in FIG.

When the supply of fluid or the like is completed and the forward force applied to the valve body 10 by the flow of the fluid is eliminated, the valve body 10 returns to the closed position due to the urging force of the spring 20 or the reverse pressure. Even if the valve body 10 rattles somewhat in the lateral direction, the valve body 10 is securely fitted into the step portion 4 of the case 1 and is positioned at the closed position, and the backflow of the fluid is reliably and completely prevented.

That is, even if the valve body 10 swings toward the closing position in a state where it is slightly shifted laterally, the sliding contact between the outer peripheral surface 12 of the valve body 10 and the inclined surface 3 of the case 1 causes the valve body 10 to slide. Is smoothly guided and fitted, so that the inner surface 13 and the bottom surface of the step portion 4 of the case 1 are in close contact with each other. Then, when there is a pressure difference that causes backflow,
Due to this pressure difference, the inner surface 13 of the valve body 10 is further pressed against the bottom surface of the step portion 4, and the larger the differential pressure (backflow pressure), the higher the sealing property and the inside of the case 10 is closed.

Moreover, the flexible piece 5 for mounting is
As described above, since the peripheral wall of the case 1 is provided in the space 6 which is airtight with respect to the flow path 30 by bending the pipe 3
A slight backflow caused by fuel or the like flowing into the case 1 from the gap between the inner periphery of the case 0 and the outer periphery of the case 1 does not occur. The backflow that passes through the gap between the inner circumference of the pipe 30 and the outer circumference of the case 1 and flows into the interior of the flow path as it is is prevented by the above-mentioned close contact portion of the sealing projection 1a.

In this closed state, the valve body 10
Is fitted in the step portion 4 of the case 1, the possibility that the valve body 10 is lifted up from the lateral direction and opened by the flow of the fluid inside the fuel tank or the like into which the pipe 30 is inserted is extremely low. .

Therefore, according to the check valve of the above-described embodiment, the check valve can be mounted simply by fitting it into the conduit 30, but the check flow is reliably and completely prevented. It is possible to ensure the ease of mounting such a check valve while maintaining the reliability of prevention.

Further, since there is almost no portion projecting more than the outer diameter of the conduit 30 (particularly, the rotation supporting portion of the valve body 10), a space around the position where the check valve is provided in a fuel tank or the like is reduced. It can be used for arrangement of other devices, etc., and the degree of freedom in design is improved. In addition, since it can be constituted by an integrally molded product including the rotation support portion of the valve body, the material cost can be reduced. Further, the valve assembly 10 and the spring 20 can be assembled simply by fitting them into the case 1, and various effects can be obtained such as reduction in assembly cost.

[0022]

According to the check valve according to the present invention, the check valve can be mounted simply by fitting it into the flow path, but the check flow is reliably and completely prevented. It is possible to ensure the ease of mounting such a check valve while maintaining the reliability of prevention.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention.

FIG. 2 is a front view showing an embodiment of the present invention.

FIG. 3 is a side view showing an embodiment of the present invention.

FIG. 4 is a plan view showing an embodiment of the present invention.

FIG. 5 is a sectional view taken along the line A in FIG. 1;

FIG. 6 is a side sectional view showing the operation of the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Case 5 ... Flexible piece 6 ... Recess 10 ... Valve element 30 ... Flow path (pipe)

Claims (2)

(57) [Scope of request for utility model registration] 1. A cylindrical case which is inserted into and attached to a flow path, and which is swingably provided in the case to allow a fluid in the flow path to flow in one direction, and to allow the fluid to flow in one direction. And a valve for opening and closing the case so as to prevent backflow in the opposite direction, wherein the case is formed in a cylindrical shape that matches the flow path shape as a whole, By bending a part of the peripheral wall and projecting inwardly of the cylinder, a space that is airtight with respect to the flow path is formed between the bent part of the peripheral wall and the inner wall of the flow path. A non-return valve, wherein a flexible piece to be locked inside is provided integrally with the case and displaceable from the outer peripheral surface side of the case into the space. 2. A cylindrical case which is inserted into and attached to a flow path, and is provided in the case so as to be swingable to allow a fluid in the flow path to flow in one direction, and to allow the fluid to flow in one direction. And a valve for opening and closing the case so as to prevent backflow in the opposite direction, wherein the case is formed in a cylindrical shape that matches the flow path shape as a whole, By bending a part of the peripheral wall and projecting inwardly of the cylinder, a space that is airtight with respect to the flow path is formed between the bent part of the peripheral wall and the inner wall of the flow path. A flexible piece that locks inside is provided integrally with the case and displaceable from the outer peripheral surface side of the case so as to enter the space, and the flexible piece is connected to the case on an upstream side in a fluid flowing direction. On the other hand, on the downstream and both sides, the case Are separated through a gap, and a portion where the peripheral wall of the case is bent is provided to be inclined so as to gradually project inward from an upstream side to a downstream side in a fluid flowing direction. A check valve, characterized in that: