JP2002071074A - Structure of connector for connecting piping - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure of a connector for connecting piping excellent in rust preventive performance and sealability even by not using stainless steel or the like as a material of a filler pipe. SOLUTION: A filler tube 4 is fittingly fixed on the smaller diameter portion 6 of a connector 5 and the filler pipe 2 is fitted on the larger diameter portion 7 side by an O-ring 8 and the filler tube 4 and the filler pipe 2 are joined by fittingly stopped with a bushing method by locking a lock piece 7a of the connector 5 side to a ringed locking protrusion 11 formed on the filler pipe 2, by surrounding covering over an entire circumference of the outside circumference of the connector 5 with an annular boot 10 formed from an elastic material such as rubber by fittingly fixing one end side of the boot 10 on the connector 5, and the seal portion 11 is formed to be used for sealing between the ringed protrusion 2a of the filler pipe 2 deformed elastically by being pressed to the wall face 1a of a fuel tank 1 on which the filler pipe 2 is mounted on the another end side of the boot 10 and the wall face 1a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe connection connector structure for connecting an inner pipe, which is a filler pipe, and an outer pipe, which is a filler tube, for a fuel tank for an automobile.

[0002]

2. Description of the Related Art Conventionally, as this kind of connector structure for pipe connection, for example, one shown in FIG. 8 is known (see Japanese Patent Application Laid-Open No. 4-248007).

According to FIG. 8, a filler tube a as an outer tube and a filler pipe b as an inner tube are connected by a pipe connection connector structure c.

That is, the pipe connection connector structure c is composed of a connector d and a retainer e.

The connector d has a small diameter portion f and a large diameter portion g. The small diameter portion f has a plurality of annular projections h formed on the outer periphery thereof. It is elastically expanded and fitted.

The large-diameter portion g of the connector d is provided with two O-rings i, i in its inner hole with a spacer k interposed.

In the retainer e, a through hole m is formed in the middle abdomen, and a pair of claw walls n facing each other are fixed so that one end is a free end and the other end is extended so as to protrude into the through hole m. It is formed as an end.

The free end side of the claw wall n extends to the connector d side, and the claw wall n engages with an annular projection P formed on the outer periphery of the filler pipe b together with the wall of the through hole m. do it,
The filler pipe b is prevented from falling out of the connector d.

An annular concave portion r is provided on the base end q side of the retainer e, and the distal end engaging portion s of the large-diameter portion g is engaged with the annular concave portion r, so that the connector d and the retainer e are mutually connected. It is locked.

[0010]

The filler tube a is usually made of a resin pipe, whereas the filler pipe b is made of a steel pipe because it is installed in a metal fuel tank (not shown). Even though the outer surface is covered with the connector d and the retainer e, there is a through hole m of the retainer e and there is a large gap between the claw walls n and the outer surface is exposed to the outside air. Therefore, it was coated with a thick rust-preventive coat and subjected to rust-proof treatment.

However, if a thick-film rust-preventive coat is applied as it is to the portion of the filler tube b that is in contact with the O-ring, there remains a problem in terms of ensuring the sealing performance. It needed to be a thin film. For this reason, the rust-preventing force at the site is inevitably degraded, and unavoidably, the filler pipe b is made thicker or made of an expensive stainless steel or the like.

In view of the above, an object of the present invention is to provide a pipe connector structure having excellent rust prevention performance and sealing properties without using stainless steel or the like as a material for a filler pipe. .

[0013]

In order to achieve the above object, a connector structure for pipe connection according to the present invention comprises an inner tube connected to the other end of a connector having one end fitted to the outer tube through an O-ring. In the pipe connection connector structure for fitting and engaging the lock piece on the connector side with the ring-shaped engagement projection formed on the inner pipe, the outer circumference of the connector is provided in the pipe connection connector structure for retaining and connecting the inner and outer pipes. Surrounded and covered by an annular boot made of elastic material such as rubber over the entire circumference,
One end of the boot is fitted to the connector, and the other end of the boot is elastically deformed by being pressed against a ring-shaped seal projection formed on the inner tube or a wall surface on a mounting side where the inner tube is mounted. A seal portion for sealing between the ring-shaped projection of the pipe or the wall surface on the mounting side is formed.

Since the connector is surrounded and covered by the boot, the inner tube connected by the connector is not exposed to the outside air and is indirectly subjected to a rust-proof treatment. It is not necessary to apply a thick-film rust-preventive coat as in the prior art. Therefore, the sealing property between the inner tube and the connector by the O-ring can be sufficiently ensured, and there is no need to use an expensive material such as stainless steel.

In the present invention, the seal portion of the boot is formed by forming an inner tube side end of the boot into a V-shaped cross section. The contact with the wall surface on the mounting side to be mounted can be made into a line contact, and it is easy to easily follow the ring-shaped seal protrusion and the wall surface shape on the mounting side, so that improvement in sealing performance can be expected.

Further, according to the present invention, when the seal portion is pressed against the ring-shaped projection of the inner tube or the wall surface on the mounting side and elastically deforms the boot, the internal pressure in the boot is increased to increase the outer pressure of the boot. And a lock confirmation mechanism for confirming that the lock piece of the connector is engaged with the ring-shaped engagement protrusion of the inner tube by the protrusion of the protrusion. Therefore, if the protruding portion of the lock confirmation mechanism protrudes outward from the boot, it is ensured that the engagement between the lock piece on the connector side and the ring-shaped engagement protrusion on the inner tube side is reliable. It is possible to make a determination and prevent a so-called pseudo lock. That is, if the engagement between the connector-side lock piece and the inner tube-side ring-shaped engagement projection is not reliable, the pressing force of the seal portion of the boot against the wall surface on the mounting side of the inner tube becomes weaker, Seal products cannot be secured. Therefore, the internal pressure in the boot cannot be sufficiently increased, and the protruding portion of the boot does not protrude due to the internal pressure. Is not certain.

Further, according to the present invention, the boot-side engaging projections engage with each other when the seal portion is pressed against the ring-shaped projection of the inner tube or the wall surface on the mounting side and elastically deforms. A boot-side engaging piece to be engaged is formed on an outer peripheral portion of the seal portion, and the locking piece of the connector is formed into a ring-like shape of the inner tube by engagement of the boot-side engaging protrusion and the boot-side engaging piece. Since the lock confirmation mechanism for confirming the engagement with the engagement protrusion is configured, if the boot-side engagement protrusion and the boot-side engagement piece are in a normal engagement relationship, the lock side on the connector side and the lock side on the connector side are not engaged. It is possible to prevent the engagement with the ring-shaped engagement protrusion on the tube side from being pseudo-locked.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is applied to a piping connector structure for connecting a filler pipe on a fuel tank side of an automobile as an outer pipe and a filler tube installed on a vehicle body side as an inner pipe. An embodiment will be described with reference to the drawings.

First, a description will be given with reference to FIG. FIG. 1 is an explanatory view schematically showing a joint structure between a filler pipe on a fuel tank side of an automobile and a filler tube on a vehicle body side.

According to FIG. 1, a clamp structure is formed by connecting a filler pipe 2 mounted on a fuel tank 1 side and a filler tube 4 installed on a fuel filler port 3a on a vehicle body 3 side with a connector 5. are doing.

Next, the details of the connector structure according to the embodiment of the present invention will be described with reference to FIGS.

FIG. 2 is a front view showing a state before the filler pipe 2 and the filler tube 4 are connected by the connector 5, and FIG.
FIG. 7 is a front view after connection.

First, in FIG. 2, the filler pipe 2 and the filler tube 4 are connected via a connector 5 made of resin.

The connector 5 comprises a small diameter portion 6 and a large diameter portion 7 arranged in the axial direction. The outer periphery of the small diameter portion 6 is formed with a plurality of projections 6a, one end of which is an oil filler port. 3
The inner peripheral portion of the other end of the filler tube 4 installed at a is fitted with a larger diameter than the general portion, and the other end of the filler tube 4 is formed on the outer peripheral portion of the small diameter portion 6. It is inserted into the recess 6b and is subjected to terminal processing.

On the inner peripheral portion of the large diameter portion 7, two O-rings 8
Are fitted to each other with the spacer 8a interposed therebetween.

Locking pieces 7a are formed on the large diameter portion 7 of the connector 5 at positions facing each other. The locking pieces 7a, 7a are formed with locking projections 7b, 7b, one end of which is connected to the large diameter portion 7, the other end of which extends toward the small diameter portion 6, and protrudes inside the large diameter portion 7. Further, it has a spring force that is biased inward of the large diameter portion 7.

The filler pipe 2 has one end mounted on the fuel tank 1 and a ring-shaped engaging projection 2a protruding from a peripheral portion of the other end at a position separated from the terminal by a predetermined width. .

The outer periphery of the large diameter portion 7 of the connector 5 is surrounded and covered with an annular boot 10 made of an elastic material such as rubber.

One end of the boot 10 is fitted and engaged with a step 5a formed by the large-diameter portion 7 and the small-diameter portion 6, and the other end protrudes from the large-diameter portion and has a V-shaped cross section. Are formed on the seal portion 11.

In the middle part of the boot 10 is formed a snapping deformation part 12 which projects inward and has a substantially U-shaped cross section and which snaps outward when an internal pressure is applied to the inside of the boot 10. On the seal portion 11 side with respect to the deformed portion 12, there is formed a projecting portion 13 which is formed thicker than the general portion and which jumps out of the boot 10 when the snap deformed portion 12 performs a snap operation. I have.

To connect the filler pipe 2 to the filler tube 4 by the connector 5, the connector 5
Is moved in the direction of the arrow shown in FIG. 2 and the filler pipe 2 is fitted from the seal portion 11 of the boot 10 to the large-diameter portion 7.
It is connected to the filler tube 4 at this time,
When the filler pipe 2 is fitted to the large-diameter portion 7, the ring-shaped engagement projection 2a rides over the locking projection 7b while expanding the lock piece 7a outward, and then the lock piece 7a is moved by its own spring force. By returning to the original position, the ring-shaped engaging projection 2a and the locking projection 7b engage as shown in FIG.
The filler pipe 2 is prevented from falling off by the connector 5 and is connected to the filler tube 4.

At this time, the outer circumference of the other end of the filler pipe 2 is in close contact with the O-rings 8, 8, so that the gap between the outer circumference of the filler pipe 2 and the inner circumference of the large diameter portion 7 is sealed in a liquid-tight manner. I have.

The joint 15 between the outer periphery of the small diameter portion of the connector 5 and the inner periphery of the filler tube 4 is sealed by a clamp body (not shown) in a liquid-tight manner.
The connector 5 constitutes the inner tube, and the filler tube 4 constitutes the outer tube.

Further, when the filler pipe 2 is fitted to the connector 5, the seal portion 11 of the boot 10 is pressed against the wall portion 1a of the fuel tank 1 on which the seal portion 11 is mounted, and is crushed. The seal between 1a and boot 10 is made.

As a result, the filler pipe 2 is connected to the boot 1
0, it is no longer exposed to the outside air because it is surrounded and covered, which is the same as indirectly subjected to rust prevention treatment, and a thick rust prevention coat as in the past is applied to the outer surface of the filler tube 2. There is no necessity, so that the sealing property between the filler pipe 2 and the connector 5 by the O-ring 8 can be sufficiently ensured, and it is not necessary to increase the thickness of the filler pipe 2 or use an expensive material such as stainless steel. .

The seal portion 11 of the boot 10
Is pressed against the wall surface 1a of the fuel tank 1 and elastically deforms to exhibit a sealing function. However, since it is formed in a V-shaped cross section, depending on the amount of elastic deformation, the front end of the wall surface 1a
To the wall surface 1a.
Can easily be followed, and improvement in sealing performance can be expected.

Further, the snapping deformation portion 1 is attached to the boot 10.
Since the projecting portion 13 is formed continuously with the second portion, the internal pressure in the boot 10 increases due to the close contact seal with the wall surface 1a of the seal portion 11, and the projecting portion 13 jumps outward. The protrusion of the protrusion 13 constitutes a lock confirmation mechanism for confirming that the lock piece 7a of the large diameter portion 7 is engaged with the ring-shaped engagement protrusion 2a of the filler pipe 2, If the protruding portion 13 protrudes outside the boot 10, it can be determined that the engagement between the lock piece 7a on the large diameter portion 7 side and the ring-shaped engagement protrusion 2a on the filler pipe 2 side is reliable. , So-called pseudo lock can be prevented.

An annular recess 14 is formed in the outer periphery of the boot 10 at a position facing the O-ring 8, and a clamp body (not shown) is fastened to the large-diameter portion 7 by the O-ring 8. A predetermined sealing pressure with the filler pipe 2 is provided. Further, the sealing property between the boot 10 and the connector 5 is also ensured.

4 and 5 show another embodiment according to the present invention. FIG. 4 is a front view showing a state before the filler pipe 2 and the filler tube 4 are connected by the connector 10, and FIG. It is a front view after.

In the present embodiment, the snapping deformation section 12 constituting the lock confirmation mechanism section in the above embodiment is described.
Instead of the projecting portion 13, a boot-side engaging piece 15 is formed at the tip of the seal portion 11, and the boot-side engaging portion 16 that engages with the boot-side engaging piece 15 is attached to the root of the seal portion 11. In the process from the dashed line to the solid line in FIG. 6, the boot-side engaging piece 15 is
When the seal portion 11 is pressed against the wall surface, the boot-side engaging piece 15 swings toward the connector 5 and engages with the boot-side engaging portion 16. .

Accordingly, the engagement of the boot-side engaging piece 15 with the boot-side engaging portion allows the lock piece 7a of the large-diameter portion 7 to engage with the ring-shaped engaging projection 2a of the filler pipe 2. The lock confirmation mechanism to confirm is configured,
If the boot-side engagement piece 15 is engaged with the boot-side engagement portion 16, the engagement between the lock piece 7a on the large diameter portion 7 and the ring-shaped engagement projection 2a on the filler pipe 2 is reliable. And so-called pseudo lock can be prevented.

FIG. 7 shows a modification of the embodiment of the present invention shown in FIG. 2 and FIG.
In addition to the ring-shaped engagement protrusion 2a, a single ring-shaped seal protrusion 2b is formed
By pressing the seal portion 11 of the boot 10 against b,
This constitutes a seal structure.

In the present embodiment, for example, the case where the filler tube 2 cannot be attached to the fuel tank 1 or the like is considered.

In the above embodiment of the present invention, the case where the outer tube is applied to a filler tube and the inner tube is applied to a filler pipe has been described. However, the pipe connecting connector structure according to the present invention is not limited to this. It is a matter of course that the present invention can be applied as a connector for connecting various other pipes.

[0045]

As described above, according to the present invention,
Since the connector is surrounded and covered by boots and the inner tube connected by the connector is subjected to rust prevention treatment, it is not necessary to apply a thick rust prevention coat on the outer surface of the inner tube as in the conventional case. Therefore, the sealing property between the inner tube and the connector by the O-ring can be sufficiently ensured, and there is no need to use an expensive material such as stainless steel.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing a connection structure of a filler pipe on a fuel tank side of an automobile and a filler tube on a vehicle body side by a pipe connection connector structure according to a first embodiment of the present invention.

FIG. 2 is a front view before a filler pipe and a filler tube 4 are connected by a connector in FIG. 1;

FIG. 3 is a front view after connection.

FIG. 4 is a front view before a filler pipe and a filler tube are connected by a connector according to a second embodiment of the present invention.

FIG. 5 is a front view after connection.

FIG. 6 is an enlarged view showing the inside of a circle in FIG. 5;

FIG. 7 is a front view after a filler pipe and a filler tube are connected by a connector according to a third embodiment of the present invention.

FIG. 8 is a front view after connecting a filler pipe and a filler tube using a conventional pipe connection connector structure.

[Explanation of symbols]

 Reference Signs List 1 fuel tank (mounting side) 1a wall surface 2 filler pipe (inner tube) 2a ring-shaped engagement protrusion 2b ring-shaped seal protrusion 4 filler tube (outer tube) 5 connector 6 small diameter portion 7 large diameter portion 7a lock piece 8 O-ring 10 Boot 11 Sealing part 13 Protruding part 15 Boot-side engaging piece 16 Boot-side engaging part

Claims (4)

[Claims] 1. An inner tube is fitted through an O-ring to the other end of a connector having one end fitted to the outer tube, and a lock piece on the connector is fitted to a ring-shaped engaging projection formed on the inner tube. In the pipe connection connector structure for retaining and connecting the inner and outer pipes, the outer circumference of the connector is surrounded and covered by an annular boot formed of an elastic material such as rubber over the entire circumference, One end of the boot is fitted to the connector, and the other end of the boot is elastically deformed by being pressed against a ring-shaped seal projection formed on the inner tube or a wall surface on a mounting side where the inner tube is mounted. A pipe connection connector structure, wherein a seal portion for sealing between a ring-shaped projection of a pipe or a wall surface on the attachment side is formed. 2. The pipe connection connector structure according to claim 1, wherein the seal portion of the boot is formed by forming an inner tube side end of the boot into a V-shaped cross section. 3. When the seal portion is pressed against a ring-shaped projection of the inner tube or a wall surface on the mounting side and elastically deforms, the internal pressure in the boot is increased, so that the seal portion jumps outward from the boot. A protrusion is formed, and a lock confirmation mechanism configured to confirm that the lock piece of the connector is engaged with the ring-shaped engagement protrusion of the inner tube by the protrusion of the protrusion is configured. Claim 1 or 2
The connector structure for pipe connection as described in the above. 4. The boot-side engaging projections engage with each other when the seal portion is pressed against the ring-shaped projection of the inner tube or the wall surface on the mounting side to elastically deform. A boot-side engaging piece is formed on an outer peripheral portion of the seal portion, and the lock piece of the connector is formed into a ring-shaped engaging projection of the inner tube by engagement of the boot-side engaging projection and the boot-side engaging piece. 3. The connector structure for pipe connection according to claim 1, wherein a lock confirmation mechanism for confirming engagement with said connector is formed.